Bzzz, slap! How to treat insect bites (home remedies included)



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Cameron Webb, University of Sydney

It’s the holidays and we’re spending more time outdoors. This means we’re exposed to the more annoying and painful aspects of summer — insect bites and stings.

There are plenty of products at the local pharmacy to treat these. Some treat the initial bite or sting, others the itchy aftermath.

What about natural remedies? Few studies have actually examined them. But if they work for you, and don’t irritate already inflamed skin, there’s likely no harm in continuing.




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Why do insects bite and sting?

When insects bite and sting, they are either defending themselves or need something from us (like blood).

Whatever the motivation, it can leave us with a painful or itchy reaction, sometimes a severe allergic reaction, or even a debilitating disease.

While insects sometimes get a bad rap, there are relatively few that actually pose a serious threat to our health.

Flies, mosquitoes

Many types of flies, especially mosquitoes, bite. In most instances, they need blood for nutrition or the development of eggs. The method of “biting” can vary between the different types of flies. While mosquitoes inject a needle-like tube to suck our blood, others chew or rasp away at our skin.

While researchers have studied what happens when mosquitoes bite, there is still much to learn about how to treat the bites.

So, avoiding mosquito bites is especially important given some can transmit pathogens that make us sick.




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We still have lots to learn about treating mosquito bites.
A/Prof Cameron Webb

Fleas, lice, mites and ticks

There are lots of other insects (such as bed bugs, fleas, lice) and other arthropods (such as mites, ticks) that bite.

But it is difficult to determine which insect has bitten us based on the bite reaction alone. This is generally because different people react in different ways to the saliva injected as they start to suck our blood.

Bees, wasps, ants

Then there are stinging insects, such as bees, wasps and ants. These are typically just defending themselves.

But as well as being painful, the venom they inject when they sting can cause potentially severe allergic reactions.

How do you best treat a sting or bite?

If you suffer potentially severe allergic reactions from bites or stings, immediately seek appropriate medical treatment. But for many other people, it is the initial painful reaction and itchy aftermath that require attention.

Despite how common insect bites can be, there is surprisingly little formal research into how best to treat them. Most of the research is focused on insect-borne diseases.

Even for recommended treatments, there is little evidence they actually work. Instead, recommendations are based on expert opinion and clinical experience.

For instance, heath authorities promote some general advice on treating insect bites and stings. This includes using pain relief medication (such as paracetamol or ibuprofen). They also advise applying a cold compress (such as a cold pack, ice, or damp cloth soaked in cold water) to the site of the sting or bite to help reduce the inflammation and to ease some of the discomfort.

Refreshing red drink in glass with ice cubes and lemon
Ice cubes aren’t just for summer cocktails. They can help reduce inflammation from insect bites and stings.
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There is also specific advice for dealing with stings and removing ticks.

However, if you do nothing, the discomfort of the bite or sting will eventually fade after a few days. The body quickly recovers, just as it would for a cut or bruise.

If you’re still in pain for more than a couple of days, or there are signs of an allergic reaction, seek medical assistance.

What about the itch?

Once the initial pain has started to fade, the itch starts. That’s because the body is reacting to the saliva injected when insects bite.

For many people, this is incredibly frustrating and it is all too easy to get trapped in a cycle of itching and scratching.

In some cases, medications, such as corticosteroid creams or antihistamines could help alleviate the itchiness. You can buy these from the pharmacy.

Then there’s calamine lotion, a mainstay in many Australian homes used to treat the itchiness caused by insect bites. But there are few studies that demonstrate it works.




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Do any home remedies work?

If you’re looking for a home remedy to treat insect bites and the itchiness that comes with it, a quick internet search will keep you busy for days.

Potential home remedies include: tea bags, banana, tea tree or other essential oils, a paste of baking soda, vinegar, aloe vera, oatmeal, honey and even onion.

There is little evidence any of these work. But not many have actually been scientifically evaluated.

Tea tree oil is one of the few. While it is said to help treat skin reactions, the oil itself can cause skin reactions if not used as directed.

However, if a home remedy works for you, and it’s not causing additional irritation, there’s no harm in using it if you’re getting some relief.

With so much uncertainty about how to treat insect bites and stings, perhaps it is best if we avoid exposure in the first place. There are plenty of insect repellents available at your local pharmacy or supermarket that do this safely and effectively.The Conversation

Cameron Webb, Clinical Associate Professor and Principal Hospital Scientist, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Would you do this at home? Why we are more likely to do stupid things on holidays



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Denis Tolkach, James Cook University and Stephen Pratt, The University of the South Pacific

As the COVID pandemic took hold in March, Ohio’s Brady Sluder went to Miami for spring break, despite urgent calls for people to stay home and socially distance.

Interviewed by CBS News, Sluder’s arrogant justfication for his trip went viral.

If I get corona, I get corona. At the end of the day, I’m not gonna let it stop me from partying […] about two months we’ve had this trip planned.

A week later — now an international “celebrity” for all the wrong reasons — he was forced to issue a grovelling apology.

If you think Sluder’s partying was stupid, we share your feelings.

With the festive season upon us, as the pandemic continues, we can only hope covidiots listen to the rules. As many of us also head off on summer breaks, now is also a good time to reflect on stupidity in tourism.

We may be tempted to think a stupid person has certain demographic or psychological characteristics. However, anyone can behave stupidly, especially in unfamiliar environments — like holidays — where it is difficult to judge the right course of action.

The laws of human stupidity

In our recently published journal article on stupidity in tourism, we see stupidity as an action without insight or sound judgement. This results in losses or harm to the perpetrator and others. In a holiday context, it can negatively affect tourists themselves, as well as other people, animals, organisations, or destinations.

Young people partying on a beach in Florida.
When bars were shut in Florida Spring Break revellers headed to the beach.
Julio Cortez/AP/AAP

In 1976, Italian economist Carlo Cipolla published a definitive essay called The Basic Laws of Human Stupidity. Although we prefer to focus on stupid behaviour rather than stupid people, we agree with his five laws:

  1. Always and inevitably, everyone underestimates the number of stupid individuals in circulation.

  2. The probability that a certain person (will) be stupid is independent of any other characteristic of that person.

  3. A stupid person is a person who causes losses to another person or a group of persons while himself deriving no gain and even possibly incurring losses.

  4. Non-stupid people always underestimate the damaging power of stupid individuals. In particular, non-stupid people constantly forget dealing with or associating with stupid people always and everywhere turns out to be a costly mistake.

  5. A stupid person is the most dangerous type of person.

Why is stupid behaviour so dangerous? Because it is irrational and so the outcome is unpredictable.

Who could have thought so many people would die when taking a selfie that you can now take out insurance on the act? Or that aeroplane passengers would throw coins into engines for good luck?

What causes stupidity?

How can we better understand our own stupid behaviour, or recognise it in others? Stupidity is generally caused by an excess of one or more of the following factors:

  • the person believing they know everything
  • the person believing they can do anything
  • the person being extremely self-centred
  • the person believing nothing will harm them
  • the person’s emotions (for example, fear or anger)
  • the person’s state (for example, exhausted or drunk).

Why stupid behaviour is more likely on holidays

Tourists can be affected by all of these factors.

Leisure tourism, by its nature, is a very self-centred and pleasure-seeking activity. People often travel to relax and enjoy themselves.




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In pursuit of trying something new or escaping their daily routine, people may go to places with very different cultures or practices than their own, or try things they wouldn’t normally do — such as adventure activities. As a result, individuals can act differently while on holidays.

There also seem to be fewer social constraints. Tourists may not follow rules and social norms while travelling, because relatives, friends, colleagues, bosses are less likely to find out. Of course, tourists may not be aware of the commonly-accepted rules of where they travelling, as well.

All of the above increases the likelihood of stupidity. And one certainly doesn’t need to travel overseas to be stupid. A case in point is a tourist who snuck into Uluru-Kata Tjuta National Park, which was closed-off in August due to COVID concerns in the local indigenous community. The woman injured her ankle and had to be rescued.

The importance of thinking first

So, what to do about stupid tourist behaviour?

Strict regulation, physical barriers, warning signs and other punitive measures alone may not work. This is seen in the case of a man who climbed over a zoo fence in 2017 to avoid the entry fee. He ended up being mauled to death by a tiger.

Tourists walking beyond a 'do not go beyond this point' sign.
Physical barriers alone do not prevent stupid behaviour.
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Education of tourists on how to behave during travels has some effect. But more importantly, tourists need to be self-aware. They need to consider what is likely to happen as a result of their behaviour, how likely is it that things will go wrong, and whether they would do this at home.

While stupidity is impossible to eliminate, it can be less frequent and do much less damage, if we take time to reflect on our behaviour and attitudes.

So, have fun during the holiday … but don’t be stupid!




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The Conversation


Denis Tolkach, Senior Lecturer, James Cook University and Stephen Pratt, Professor, The University of the South Pacific

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Global emissions are down by an unprecedented 7% — but don’t start celebrating just yet



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Pep Canadell, CSIRO; Corinne Le Quéré, University of East Anglia; Glen Peters, Center for International Climate and Environment Research – Oslo; Matthew William Jones, University of East Anglia; Philippe Ciais, Commissariat à l’énergie atomique et aux énergies alternatives (CEA); Pierre Friedlingstein, University of Exeter; Robbie Andrew, Center for International Climate and Environment Research – Oslo, and Rob Jackson, Stanford University

Global emissions are expected to decline by about 7% in 2020 (or 2.4 billion tonnes of carbon dioxide) compared to 2019 — an unprecedented drop due to the slowdown in economic activity associated with the COVID-19 pandemic.

To put this into perspective, the Global Financial Crisis in 2008 saw a 1.5% drop in global emissions compared to 2007. This year’s emissions decline is more than four times larger.

These are the findings we show in the 15th global carbon budget, an annual report card of the Global Carbon Project on the sources and removals of carbon dioxide, the primary driver of human caused climate change.

It may sound like welcome news, but we can’t celebrate yet. A rapid bounce back of emissions to pre-COVID levels is likely, possibly by as soon as next year. A recent study found emissions in China snapped back to above last year’s levels during late spring when economic activity began to return to normal.

These findings come ahead of the Climate Ambition Summit on Saturday, where global leaders will demonstrate their commitments to climate action five years since the Paris Agreement. This huge drop in emissions should be taken as a unique opportunity to divert the historical course of emissions growth for good.

Emissions in the pandemic year

The total global fossil carbon dioxide emissions for 2020 are estimated to be 34 billion tonnes of carbon dioxide.

Estimated emissions at the beginning of December are lower than their levels in December last year, at least in the transport sectors. However, emissions have been edging back up since the peak global daily decline of 17% in early April.




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The decline in emissions in 2020 was particularly steep in the United States (12%) and European Union (11%), where emissions were already declining before the pandemic, mainly from reductions in coal use.

Emissions from India dropped by 9%, while emissions from China, which have returned to close or above 2019 values, saw an estimated drop of only about 1.7%.

Australian greenhouse gas emissions during the peak of the pandemic lockdown (the quarter of March to June 2020) were lower by 6.2% compared to the previous quarter. The largest declines were seen in transport and fugitive emissions (emissions released during the extraction, processing and transport of fossil fuels).

A chart showing the emissions decline for China, US, India, EU, and the rest of the world.
The 2020 emission decline was particularly steep in the United States and European Union. While China’s emissions also dropped steeply, they snapped back later in the year.
Pep Canadell, Author provided

Globally, the transport sector also contributed the most to the 2020 emissions drop, particularly “surface transport” (cars, vans and trucks). At the peak of the pandemic lockdowns, the usual levels of transport emissions were halved in many countries, such as in the US and Europe.

While aviation activity collapsed by 75%, its contribution to the total decline was relatively small given the sector only accounts for about 2.8% of the total emissions on an average year. The number of global flights was still down 45% as of the first week of December.

A chart showing the emissions decline for different sectors.
The industry sector, specifically metals production, chemicals and manufacturing, was the second largest contributor in emissions declines.
Pep Canadell, Author provided

Global emissions were already slowing down pre-COVID

Overall, global emissions have increased by 61% since 1990. But the pace of this growth has varied.

In the early 1990s, the growth in emissions slowed down due to the collapse of the former Soviet Union, but then increased very quickly during the 2000s, by 3% per year on average. This was, in part, due to the rise of China as an economic power.




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Over the last decade, however, the pace of emissions began to slow again, with an increase just below 1% per year. And emissions in 2019 didn’t grow much, if at all, when compared to 2018.

Behind the global slowing trend, there are 24 countries that had carbon dioxide fossil emissions declining for at least one decade while their economy continued to grow. They include many European countries such as the Denmark, the UK and Spain, and the USA, Mexico and Japan. For the rest of the world, emissions continued to grow until 2019.

This chart shows how global fossil carbon dioxide emissions have increased.
This chart shows how global fossil carbon dioxide emissions have increased since the 1990s. Note the drops in the early 1990s, in 2008, and the huge drop in 2020.
Pep Canadell, Author provided

An opportunity to boost ambition

The pandemic, along with other recent trends such as the shift towards clean energy, have placed us at a crossroad: the choices we make today can change the course of global emissions.

In addition to the slow down in global emissions in recent years, and this year’s drop, there are now dozens of countries that have pledged to reach net zero emissions by mid century or soon after.

How the emissions of different countries have changed over time.

Importantly, the first (China), second (USA), third (European Union), sixth (Japan) and ninth (South Korea) top emitters — together responsible for over 60% of the global fossil carbon dioxide emissions — have either legally binding pledges or serious ambitions to reach net zero emissions by 2050 or soon after.




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Coal production, the largest fossil fuel source of carbon dioxide emissions, peaked in 2013. Its decline continues to this date; however, increasing natural gas and oil negate much of this decline in emissions.

How the emissions from coal, oil, gas, and cement sectors changed over time.
How the emissions from coal, oil, gas, and cement sectors changed over time.
Pep Canadell, Author provided

We are in the midst of extraordinary levels of economic investment in response to the pandemic. If economic investment is appropriately directed, it could enable the rapid expansion of technologies and services to put us on track towards net zero emissions.

Many countries have already committed to green recovery plans, such as South Korea and the EU, although investments continue to be dominated by the support of fossil-based infrastructure.

As global leaders prepare for tomorrow’s summit, they have an opportunity like never before. The choices we make now can have a disproportionate impact on the future trajectory of emissions, and keep temperature rise well and truly below 2℃.




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The Conversation


Pep Canadell, Chief research scientist, Climate Science Centre, CSIRO Oceans and Atmosphere; and Executive Director, Global Carbon Project, CSIRO; Corinne Le Quéré, Royal Society Research Professor, University of East Anglia; Glen Peters, Research Director, Center for International Climate and Environment Research – Oslo; Matthew William Jones, Senior Research Associate, University of East Anglia; Philippe Ciais, Directeur de recherche au Laboratoire des science du climat et de l’environnement, Institut Pierre-Simon Laplace, Commissariat à l’énergie atomique et aux énergies alternatives (CEA); Pierre Friedlingstein, Chair, Mathematical Modelling of Climate, University of Exeter; Robbie Andrew, Senior Researcher, Center for International Climate and Environment Research – Oslo, and Rob Jackson, Professor, Department of Earth System Science, and Chair of the Global Carbon Project, Stanford University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Australia needs a national approach to combat the health effects of climate change



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Stephen Duckett, Grattan Institute and Will Mackey, Grattan Institute

Australia has just recorded its hottest November on record, only months after the devastating bushfires of last summer that ruined the lives and livelihoods of thousands.

Climate change is doing its deadly work. Australia is already about 1.5℃ warmer than it was 100 years ago, and there is worse to come.

As our continent continues to warm, we will have to endure harsher heatwaves and more severe storms. The cyclones in our far north will be more intense, causing floods that will destroy homes, businesses and lives.

Health authorities need to do more. The federal health department says its vision is “better health and wellbeing for all Australians, now and for future generations”. Yet there is little mention of the greatest health risk facing our future generations: climate change.

Currently, what the World Health Organisation calls one of the world’s greatest health risks doesn’t rate a mention in Australia’s Long Term National Health Plan, or the Department of Health’s forward-looking Corporate Plan.

The department’s A$5 billion investment plan for the Medical Research Future Fund describes 20 funding initiatives for the next decade and identifies “areas of national priority”. But it doesn’t once mention climate change.




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Why the silence?

At the national level, there is an evident unwillingness to speak about the damage climate change is already doing to Australians’ health. And things are only going to get worse.

The Grattan Institute has today released a report that identifies ways the health sector should adapt to the changing climate in Australia.

A bushfire burns.
Bushfires can have many and varied effects on human health.
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The coronavirus pandemic provides a model. Australia’s response to COVID-19 was led by a national cabinet and informed by the national and state chief medical and health officers, meeting as the Australian Health Protection Principal Committee (AHPPC).

Our political leaders listened to the science presented by these expert advisers. They used this evidence and advice to make unprecedented decisions in unprecedented times to protect the lives and livelihoods of millions of Australians.

They must do the same with climate change. Governments should establish a “climate change and health” subcommittee of the AHPPC, tasked with generating research and providing advice on climate change adaption and mitigation.

The new subcommittee should incorporate research that touches on climate change and is already done by existing committees such as the Communicable Diseases Network Australia, the Environmental Health Standing Committee, and the National Health Emergency Standing Committee. Officials on the climate change and health subcommittee should meet regularly, share strategies, and encourage coordinated and consistent national action where appropriate.




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Time to step up

More must be done at the national level. The Commonwealth Department of Health must add the health risks posed by climate change to its priority list. Climate change should feature prominently in its Long Term National Health Plan and in its National Preventive Health Strategy, currently in development, to ensure proper resources are made available.

All governments should ensure the health sector incorporates climate change into risk assessments and disaster planning. This could be done by mandating a new requirement in the National Safety and Quality Health Service Standards for health services to assess climate change risks.

With the world’s sixth-largest landmass spanning a wide variety of climates, Australia faces a unique combination of climate-related health challenges. Our research institutions must get more support to pursue climate-health knowledge. Between 2013 and 2020, the National Health and Medical Research Council (NHMRC) awarded less than A$2 million out of A$6.3 billion to climate-and-health research topics — just 0.03% of the total.

After years of little interest, the NHMRC has just announced A$10 million in dedicated funding to “improve Australia’s preparedness and responsiveness to human health threats from changing environmental conditions and extreme weather events”, to begin in 2021. This is a step in the right direction, but Australia will need to provide much more support for climate change and health research.

The Medical Research Future Fund investment plan should have a dedicated focus on climate change and health research, so Australia’s researchers can help us all better understand our problem.

In the coming years and decades, Australia’s climate will become more dangerous and destructive. In 2020, with strong leadership and evidence-based decision-making, Australia had remarkable success in confronting the challenges of COVID-19. Now we must do it again on climate change.




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The Conversation


Stephen Duckett, Director, Health Program, Grattan Institute and Will Mackey, Senior Associate, Grattan Institute

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate change is resulting in profound, immediate and worsening health impacts, over 120 researchers say



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Celia McMichael, University of Melbourne; Ilan Kelman, UCL; Shouro Dasgupta, Università Ca’Foscari, and Sonja Ayeb-Karlsson, United Nations University

Climate change is resulting in profound, immediate and worsening health impacts, and no country is immune, a major new report from more than 120 researchers has declared.

This year’s annual report of The Lancet Countdown on Health and Climate Change, released today, presents the latest data on health impacts from a changing climate.

Among its results, the report found there were 296,000 heat-related premature deaths in people over 65 years in 2018 (a 54% increase in the last two decades), and that global yield potential for major crops declined by 1.8–5.6% between 1981 and 2019.

We are part of the Lancet Countdown sub-working group focusing on human migration in a warming world. We estimate that, based on current population data, 145 million people face potential inundation with global mean sea-level rise of one metre. This jumps to 565 million people with a five metre sea-level rise.




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Unless urgent action is taken, the health consequences of climate change will worsen. A globally coordinated effort tackling COVID-19 and climate change in unison is vital, and will mean a triple win: better public health, a more sustainable economy and environmental protection.

Drought, fires and excessive heat

The 2020 report brings together research from a range of fields, including climate science, geography, economics and public health. It focuses on 43 global indicators, such as altered geographic spread of infectious disease, health benefits of low-carbon diets, net carbon pricing, climate migration and heat-related deaths.

The Lancet Countdown on Health and Climate Change: 2020 report.

The five hottest years on record have occurred since 2015, and 2020 is on track to be the first or second hottest year on record.

The 2020 Lancet Countdown report found extreme heat continues to rise in every region in the world and particularly affects the elderly, especially those in Japan, northern India, eastern China and central Europe. It is also a big problem for those with pre-existing health conditions and outdoor workers in the agricultural and construction sectors.




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While attributing heat-related deaths to climate change isn’t straightforward, rising temperatures and humidity will mean we can expect heat-related deaths to increase further.

Climate change is also an important contributing factor to drought. The report found that in 2019 excess drought affected over twice the global land surface area, compared with the 1950-2005 baseline.

Drought and health are intertwined. Drought can cause dwindling drinking water supplies, reduced livestock and crop productivity, and an increased risk of bushfire.

Mental health is also at risk, as Australian research from earlier this year confirmed. This looked at the declining mental health of drought-affected farmers in the Murray-Darling Basin over 14 years.

Smoke and fire in the understory of a eucalyptus forest
More than 445 deaths were attributed to the smoke from the Black Summer bushfires.
Shutterstock

Further, the Lancet Countdown report found that between 2015 and 2019, the number of people exposed to bushfires increased in 128 countries, compared with a 2001-2004 baseline.




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Climate change is bringing a new world of bushfires


Climate change worsens risk factors for more frequent and intense bushfires. We need only look to last summer’s unprecedented bushfires in Australia as a stark illustration. The number of people exposed to the bushfires was amplified by expanding settlements and inadequate risk reduction measures.

Sea level rise, human migration and health

As the world warms and the sea rises, millions of people will be exposed to coastal changes, including inundation and erosion.

Sea-level rise has direct and indirect consequences for human health. In some places, water and soil quality and supply will be compromised due to the intrusion of saltwater. Flooding and wave power will damage infrastructure, including drinking water and sanitation services. And disease vector ecology will also change, such as higher mosquito densities in coastal habitats, potentially causing greater transmission of infectious diseases like dengue or malaria.

However, people and communities may adapt by moving away. In Fiji, for example, at least four communities have relocated in response to coastal changes. The Fijian government notes planned relocation will be a last resort only when other adaptation options are exhausted.




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Relocation might also lead to health threats . This includes physical health consequences from altered diets, as fishing and subsistence agriculture may be disrupted. There are also mental health impacts from people losing their attachments and connections to their places of belonging.

But sometimes, migration responses to climate change can have health benefits. Moving from vulnerable coastlines might reduce exposure to environmental hazards such as flooding, be an impetus to seek healthier livelihoods and lifestyles, and improve access to health services.

Our estimation of the number of people facing potential inundation is based on projections of global mean sea-level rise and on current population data.

In a high emissions scenario with warming of 4.5℃, seas could rise by one metre by 2100 relative to 1986–2005. This would see 145 million people face potential inundation.

A collapse of the Western Antarctic Ice Sheet could cause five to six metres of sea level rise. Under this extreme scenario, 565 million people may be inundated.




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It is important to note, however, that uncertainties constrain our ability to forecast migration numbers due to sea-level rise. These uncertainties include future environmental and demographic factors and potential adaptation (and maladaptation) responses, such as living with water or coastal fortification.

So is there any good news?

The 2020 Lancet Countdown report notes improvements in some instances, as some sectors and countries take bold steps to respond to climate change.

We are seeing, for example, health benefits emerging from the transition to clean energy. Deaths from air pollution attributed to coal-fired power have declined from 440,000 in 2015 to 400,000 in 2018, despite overall population increases.

But more must be done: we need sustained greenhouse gas emission cuts, increased greenhouse gas absorption and proactive adaptation actions. Yet global efforts to address climate change still fall short of the commitments made in the Paris Agreement five years ago.

We cannot afford to focus attention on the COVID-19 pandemic at the expense of climate action.

If responses to the economic impacts of COVID-19 align with an effective response to climate change, we’ll see immense benefits for human health, with cleaner air, healthier diets and more liveable cities.The Conversation

Celia McMichael, Senior Lecturer in Geography, University of Melbourne; Ilan Kelman, Professor of Disasters and Health, UCL; Shouro Dasgupta, Lecturer in Environmental Economics, Università Ca’Foscari, and Sonja Ayeb-Karlsson, Senior Researcher, Institute for Environment and Human Security (UNU-EHS), United Nations University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Planning a road trip in a pandemic? 11 tips for before you leave, on the road and when you arrive



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Thea van de Mortel, Griffith University

As restrictions ease around the country and the prospect of travel beckons, many of us will be planning road trips for the holiday season.

To ensure your trip is memorable in the best rather than the worst way, here are some things you and your fellow travellers can do to reduce the risk of becoming infected with, or spreading, COVID on your trip.

Before you go

1. Check for any travel or other COVID-specific restrictions or rules in the areas you will be travelling through or to, before you go. These can change rapidly and may include restrictions on how far you can travel, how many people per square metre are allowed in public spaces, and whether you need border passes or to wear a mask. Each state or territory has its own health department or government COVID website you can check.

2. Don’t take COVID with you. If anyone in your group has COVID-like symptoms, however mild, it is important to be tested and cleared for COVID before leaving. Common symptoms may include fever or chills, muscle aches, sore throat, cough, runny nose, difficulty breathing, new loss of taste or smell, and vomiting or diarrhoea.

3. Pack masks, disinfectant wipes and hand sanitiser. The two most likely ways of catching COVID are inhaling viral particles an infected person sheds when they cough, sneeze, laugh, talk or breathe; and ingesting particles by touching contaminated objects and then touching your face or food. Masks (and social distancing) can help reduce the former risk, while avoiding touching your face, frequent hand hygiene and cleaning surfaces can reduce the latter. So pack masks, wipes and hand sanitiser. Hand sanitiser should contain at least 60% alcohol.

4. Pack your own pillows and linen. We know people infected with SARS-CoV-2, the virus that causes COVID, can shed virus onto linen and pillows (and other surfaces), even when asymptomatic. We also know respiratory viruses can penetrate pillow covers and get into the microfibre stuffing. So you might want to consider bringing your own pillows and linen.

On your trip

5. Use disinfectant wipes to clean high-touch surfaces in your hire car. These would include door and window handles or buttons, light switches, seat adjuster controls, radio controls, the steering wheel, glove box button, gear/drive and handbrake levers, rear-view mirrors and mirror controls.

6. How about singing in the car? The more vigorous the activity, the greater the opportunity to release droplets and aerosols and the further these will travel. So, laughing and singing will release more of these than talking, and talking will release more than breathing. However, if you are travelling in a family group, or with your housemates, then you have been in close contact with one another at home and the additional risk would be low.




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7. Maintain social distancing at service stations. Leave at least 1.5 metres between you and the next person while paying for fuel, ordering food and when using the bathroom. Make sure you wash or sanitise your hands after touching surfaces such as petrol pumps, door handles, bathroom taps, and before getting back in your car.

Filling car up with petrol at service station
Wash or sanitise your hands after using the petrol pump.
Shutterstock

8. Pay with cards rather than cash to avoid touching money. Many people can handle bills and coins over a long duration of time, providing many opportunities to transfer disease-causing microbes from one person to the next. Using contactless payment also helps maintain social distancing.

9. It’s safer to eat outdoors than indoors if stopping for a snack or lunch. That’s because large volumes of air dilute the density of viral particles in the air. Evidence from a study of COVID clusters in Japan suggests the chance of transmitting COVID is more than 18 times higher inside than outside.




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When you arrive

10. Is your hotel or rented accommodation COVID-safe? Ask the accommodation provider what steps they have taken to make the place less conducive to spreading COVID. For example, have they introduced extra cleaning or disinfection?

11. Use disinfectant wipes in rented accommodation to clean high-touch surfaces such as door handles, light switches, cupboard handles, taps and toilet flush buttons. You can also put dishes and cutlery through the dishwasher on a hot cycle. This is because the virus can remain viable (able to cause infection) on surfaces for many days.

Following these simple steps can help to keep your trip memorable in the best possible way. Happy holidays!The Conversation

Thea van de Mortel, Professor, Nursing and Deputy Head (Learning & Teaching), School of Nursing and Midwifery, Griffith University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

UN report says up to 850,000 animal viruses could be caught by humans, unless we protect nature



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Katie Woolaston, Queensland University of Technology and Judith Lorraine Fisher

Human damage to biodiversity is leading us into a pandemic era. The virus that causes COVID-19, for example, is linked to similar viruses in bats, which may have been passed to humans via pangolins or another species.

Environmental destruction such as land clearing, deforestation, climate change, intense agriculture and the wildlife trade is putting humans into closer contact with wildlife. Animals carry microbes that can be transferred to people during these encounters.

A major report released today says up to 850,000 undiscovered viruses which could be transferred to humans are thought to exist in mammal and avian hosts.

The report, by The United Nations’ Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), says to avoid future pandemics, humans must urgently transform our relationship with the environment.

Covid-19 graphic
Microbes can pass from animals to humans, causing disease pandemics.
Shutterstock

Humans costs are mounting

The report is the result of a week-long virtual workshop in July this year, attended by leading experts. It says a review of scientific evidence shows:

…pandemics are becoming more frequent, driven by a continued rise in the underlying emerging disease events that spark them. Without preventative strategies, pandemics will emerge more often, spread more rapidly, kill more people, and affect the global economy with more devastating impact than ever before.

The report says, on average, five new diseases are transferred from animals to humans every year – all with pandemic potential. In the past century, these have included:

  • the Ebola virus (from fruit bats),
  • AIDS (from chimpazees)
  • Lyme disease (from ticks)
  • the Hendra virus (which first erupted at a Brisbane racing stable in 1994).

The report says an estimated 1.7 million currently undiscovered viruses are thought to exist in mammal and avian hosts. Of these, 540,000-850,000 could infect humans.

But rather than prioritising the prevention of pandemic outbreaks, governments around the world primarily focus on responding – through early detection, containment and hope for rapid development of vaccines and medicines.

Doctor giving injection to patient
Governments are focused on pandemic responses such as developing vaccines, rather than prevention.
Shutterstock

As the report states, COVID-19 demonstrates:

…this is a slow and uncertain path, and as the global population waits for vaccines to become available, the human costs are mounting, in lives lost, sickness endured, economic collapse, and lost livelihoods.

This approach can also damage biodiversity – for example, leading to large culls of identified carrier-species. Tens of thousands of wild animals were culled in China after the SARS outbreak and bats continue to be persecuted after the onset of COVID-19.

The report says women and Indigenous communities are particularly disadvantaged by pandemics. Women represent more then 70% of social and health-care workers globally, and past pandemics have disproportionately harmed indigenous people, often due to geographical isolation.




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It says pandemics and other emerging zoonoses (diseases that have jumped from animals to humans) likely cause more than US$1 trillion in economic damages annually. As of July 2020, the cost of COVID-19 was estimated at US $8-16 trillion globally. The costs of preventing the next pandemic are likely to be 100 times less than that.

People wearing masks in a crowd
The cost to governments of dealing with pandemics far outweighs the cost of prevention.
Shutterstock

A way forward

The IPBES report identifies potential ways forward. These include:

• increased intergovernmental cooperation, such as a council on pandemic prevention, that could lead to a binding international agreement on targets for pandemic prevention measures

• global implementation of OneHealth policies – policies on human health, animal health and the environment which are integrated, rather than “siloed” and considered in isolation

• a reduction in land-use change, by expanding protected areas, restoring habitat and implementing financial disincentives such as taxes on meat consumption

• policies to reduce wildlife trade and the risks associated with it, such as increasing sanitation and safety in wild animal markets, increased biosecurity measures and enhanced enforcement around illegal trade.

Societal and individual behaviour change will also be needed. Exponential growth in consumption, often driven by developed countries, has led to the repeated emergence of diseases from less-developed countries where the commodities are produced.

So how do we bring about social change that can reduce consumption? Measures proposed in the report include:

  • education policies

  • labelling high pandemic-risk consumption patterns, such as captive wildlife for sale as pets as either “wild-caught” or “captive-bred” with information on the country where it was bred or captured

  • providing incentives for sustainable behaviour

  • increasing food security to reduce the need for wildlife consumption.

People inspecting haul of wildlife products
Cracking down on the illegal wildlife trade will help prevent pandemics.
AP

An Australian response

Australia was one of the founding member countries of IPBES in 2012 and so has made an informal, non-binding commitment to follow its science and policy evidence.

However, there are no guarantees it will accept the recommendations of the IPBES report, given the Australian government’s underwhelming recent record on environmental policy.

For example, in recent months the government has so far refused to sign the Leaders’ Pledge for Nature. The pledge, instigated by the UN, includes a commitment to taking a OneHealth approach – which considers health and environmental sustainability together – when devising policies and making decisions.

The government cut funding of environmental studies courses by 30%. It has sought to reduce so called “green tape” in national environmental legislation, and its economic response to the pandemic will be led by industry and mining – a focus that creates further pandemic potential.




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Finally, Australia is one of few countries without a national centre for disease control and pandemics.

But there are good reasons for hope. It’s within Australia’s means to build an organisation focused on a OneHealth approach. Australia is one of the most biologically diverse countries on the planet and Australians are willing to protect it. Further, many investors believe proper environmental policy will aid Australia’s economic recovery.

Finally, we have countless passionate experts and traditional owners willing to do the hard work around policy design and implementation.

As this new report demonstrates, we know the origins of pandemics, and this gives us the power to prevent them.The Conversation

Katie Woolaston, Lawyer, Queensland University of Technology and Judith Lorraine Fisher, Adjunct Professor University of Western Australia, Institute of Agriculture

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Climate explained: does a delay in COP26 climate talks hit our efforts to reduce carbon emissions?



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Chris Turney, UNSW


CC BY-ND

Climate Explained is a collaboration between The Conversation, Stuff and the New Zealand Science Media Centre to answer your questions about climate change.

If you have a question you’d like an expert to answer, please send it to climate.change@stuff.co.nz


Will the delay of the COP26 UN climate negotiations impact international action to decarbonise? Would catch-up talks help? Could the talks collapse because countries stopped paying their dues?

The 26th Conference of the Parties — better known as COP26 — is the United Nations climate change conference that was scheduled to be held in Glasgow, UK, during the first two weeks of November 2020.

But in April this year the COVID-19 pandemic led to the event being postponed, then later rescheduled to November 2021.

That’s a 12-month delay on a meeting of representatives from nearly 200 countries, including New Zealand, charged with monitoring and implementing the UN’s Framework Convention on Climate Change (UNFCCC).




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It will be crucial to make progress towards the goals of the 2015 Paris Agreement, which aims to limit average global warming to 1.5-2℃ this century, relative to the 1890s (the so-called “preindustrial period”).

Preventing ‘Hothouse Earth’

The temperature target agreed in Paris was carefully chosen. Numerous scientific studies show an increase beyond 2℃ would activate self-reinforcing feedbacks in the climate system (such as a weakening of ocean and land carbon sinks). This would tip our planet into an extreme “Hothouse Earth” that could persist for millennia, regardless of what happens with future emissions.

To avoid this scenario, the legally binding UN agreement encourages all participating nations to reduce their emissions of greenhouse gases as soon as possible.

As part of the Paris Agreement, developed countries agreed to provide, from 2020, US$100 billion to support developing countries to mitigate and adapt to climate change.

Unfortunately, the current trajectory of global emissions is on track to increase global average temperatures by more than 2℃ and possibly as much as 4℃, far exceeding the target set in Paris.

One recent study put the economic costs of failing to meet the Paris goals up to an eye-watering US$600 trillion by 2100, effectively keeping the planet in permanent recession.

National representatives are expected to arrive in Glasgow next year with substantially strengthened plans to reduce emissions and meet their commitments to support developing countries.

The pandemic and emissions

There is no doubt the gathering of 30,000 delegates in Glasgow will come at a time of ongoing uncertainty about COVID-19 and the largest shock to the global economy since the Great Depression of the 1930s. The pandemic is a game changer but it’s not yet clear whether this is good or bad for reducing emissions.

Many of us have made substantial cuts to our travel and embraced remote work and online video chat, particularly at the height of the pandemic. Google and Apple data suggest more than half of the world’s population reduced their travel by more than half in April.

Unfortunately, greenhouse gas emissions have remained stubbornly high. Daily global carbon dioxide emissions fell by as much as 17% in early April. But as the world’s economy started to recover, emissions bounced back, according to the UN, with 2020 likely experiencing only a 4-7% decline in carbon dioxide relative to 2019.

To meet the Paris target and limit warming to 1.5℃, the world needs to achieve cuts of 7.6% year-on-year for the next decade, and effectively reach zero emissions by 2050.

More work to do

The sobering reality is nations have a lot more work to do to decarbonise their economies. But for many national governments, the thorny question is how to achieve more ambitious emission targets while at the same time rebuilding economies battered by COVID-19.

Although the UN has a large financial shortfall of US$711 million (at the end of 2019) due to some nations failing to pay their annual dues — with the US, Brazil and Saudi Arabia the worst offenders — there is no suggestion of cancelling the COP26 meeting next year.

Catch-up talks have indeed been mooted but so far nothing has been publicly announced. That’s not to say there aren’t intensive negotiations and commitments being made in advance of the COP26 meeting in Glasgow. And there are some positive signs.

A pandemic recovery

As the world moves towards an economic recovery after the pandemic, some major economies are tilting towards a green stimulus and public commitments to reduce fossil fuel investments.

For example, China is the world’s largest emitter of carbon dioxide and took the opportunity at the UN General Assembly 75th anniversary last month to announce it will reach peak carbon emissions by 2030 and achieve carbon neutrality by 2060.




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Arguably more ambitious is the proposed European Green Deal announced in late 2019. It aims to slash greenhouse gas emissions by half over the next decade and make Europe the first carbon-neutral continent.

To help achieve this, a carbon tax is proposed for imports into the European Union. This threatens to have far-reaching implications for European trading partners such as New Zealand and Australia.




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In parallel to these government announcements, industry is also making commitments to decarbonise. The multi-trillion-dollar financial sector is adding pressure by focusing on companies at risk from climate change and identifying so-called “stranded assets”.

These pronouncements will help boost the negotiations for more stringent cuts to emissions as delegates prepare for the COP26 meeting in Glasgow next year. This can only put more pressure on all nations to be more ambitious.

Attention will inevitably focus on the world’s largest historic emitter, the US, which is formally leaving the Paris Agreement on November 4 this year, the day after the 2020 presidential election.

So the COP26 won’t collapse, but the year’s delay to the meeting may give the world the breathing space it so desperately needs to realise the ambition of the Paris Agreement and avoid the worst of climate change.The Conversation

Chris Turney, Professor of Earth Science and Climate Change, Director of Chronos 14Carbon-Cycle Facility, Director of PANGEA Research Centre, and UNSW Node Director of ARC Centre for Excellence in Australian Biodiversity and Heritage, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Millions of face masks are being thrown away during COVID-19. Here’s how to choose the best one for the planet



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Mayuri Wijayasundara, Deakin University

Face masks are part of our daily lives during the pandemic. Many are made from plastics and designed to be used just once, which means thousands of tonnes of extra waste going to landfill.

Masks may help stop the spread of the coronavirus. But according to one estimate, if everyone in the United Kingdom used a single-use mask each day for a year, it would create 66,000 tonnes of contaminated waste and 57,000 tonnes of plastic packaging.

Evidence also suggests masks may be a source of harmful microplastic fibres on land and in waterways and litter.

So let’s look at how face masks might be designed to cause minimal harm to the environment, while still doing their job – and which type is best for you.

A woman holding and wearing an N95 mask
N95 masks are used in hospital settings.
Shutterstock

Circular thinking

China is the world’s biggest face mask manufacturer. Its daily output of face masks reportedly reached 116 million units in February this year. That creates a big waste management problem around the world.

One way to address this is to adopt “circular design” principles. This thinking seeks to reduce waste and pollution through product design, keep products and materials in use, and regenerate natural systems.




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When it comes to face masks, the three common types are cloth, surgical and N-95. N-95 masks offer the highest level of protection, blocking about 95% of airborne particles. Cloth masks are designed to be used more than once, while surgical and N-95 masks are usually intended for single use.

Face masks may consist of one or more layers, each with different functions:

  • an outermost layer, designed to repel liquids such as water
  • the innermost layer, which absorbs moisture and allows comfort and breathability
  • a non-absorbent middle layer, to filter particles.
Two people watching a sports match wearing masks
Surgical masks are generally intended as single-use items.
BrendanThorne/AAP

Each type of mask is made of different materials and used in varying settings:

– N-95 masks: These are designed to protect the wearer from 95% of airborne particles and are largely worn by health workers. N-95 masks are designed to fit closely to the face and are usually worn only once. N-95 masks comprise:

  • a strap (polyisoprene)
  • staples (steel)
  • nose foam (polyurethane)
  • nose clip (aluminum)
  • filter (polypropylene)
  • valve diaphragm (polyisoprene).

– Surgical masks: These are designed to protect sterile environments from the wearer, acting as barrier to droplets or aerosols. Generally intended as single-use items, they comprise mostly polypropylene between two layers of non-woven fabric.

– Cloth masks: These types of masks are worn by the general public. Some are homemade from fabric scraps or old clothing. They may be wholly reusable, or partially reusable with replaceable filters that must be disposed of.

These masks typically comprise an outer layer of polyester or polypropylene (or in some cases, cotton), and an inner layer designed for breathability and comfort – usually cotton or a cotton-polyester blend.

Research suggests cloth masks are less effective at filtering particles than medical masks, but may may give some protection if well-fitted and properly designed. Health advice is available to help guide their use.

Cloth masks
Many cloth masks are handmade, and can be reused.
Shutterstock

Designing for a healthier environment

It’s important to note that any attempt to redesign face masks must ensure they offer adequate protection to the wearer. Where masks are used in a medical setting, design changes must also meet official standards such as barrier efficiency, breathing capacity and fire resistance.

With this in mind, reducing the environmental harm caused by masks could be done in several ways:

– Design with more reusable parts

Evidence suggests reusable cloth masks perform almost as well as single-use masks, but without the associated waste. One life cycle assessment conducted in the UK found masks that could be washed and reused were the best option for the environment. Reusable masks with replaceable filters were the second-best option.

The study also found having a higher number of masks in rotation to allow for machine washing was better for the environment than manual washing.

– Make masks easier to dispose of or recyle

In high-risk settings such as hospitals and clinics, the reuse of masks may not be possible or desirable, meaning they must be disposed of. In medical settings, there are systems in place for disposal of such protective gear, which usually involves segregation and incineration.

But the general public must dispose of masks themselves. Because masks usually comprise different materials, this can be complicated. For example, recovering the components of a N-95 mask for recycling would involve putting the straps, nose foam, filter and valve in one bin and the metal staples and nose clip in another. And some recyclers may see mask recycling as a health risk. These difficulties mean masks often end up in landfill.

Masks would be easier to recycle if the were made of fewer materials and were easy to disassemble.

– Use biodegradable materials

For single-use items, placing synthetics with biodegradable materials would be a first step in circular design thinking.

The abaca plant, a relative of the banana tree, offers one potential option. Its leaf fibre reportedly repels water better than traditional face masks, is as strong as polymer and decomposes within two months. Most abaca is currently produced in the Philippines.

Face mask on the ground in front of bins
Recycling of face masks can be complicated.
Shutterstock

Which mask should you choose?

From a purely environmental perspective, research suggests owning multiple reusable face masks, and machine-washing them together, is the best option. Using filters with reusable face masks is a second-best option.

But when choosing a mask, consider where you will wear it. Unless cloth masks are shown to be as effective as other masks, health-care workers should not use them. But they may be suitable in low-risk everyday settings.

In the longer term, governments and manufacturers must make every effort to design masks that will not harm the planet – and consumers should demand this. Face masks will probably be ubiquitous on our streets for months to come. But once the pandemic is over, the environmental legacy may last for decades, if not centuries.




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The Conversation


Mayuri Wijayasundara, Lecturer, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

La Niña will give us a wet summer. That’s great weather for mozzies



Geoff Whalan/Flickr, CC BY-NC-ND

Cameron Webb, University of Sydney

The return of the La Niña weather pattern will see a wetter spring and summer in many parts of Australia.

We know mosquitoes need water to complete their life cycle. So does this mean Australia can expect a bumper mozzie season? How about a rise in mosquito-borne disease?

While we’ve seen more mosquitoes during past La Niña events, and we may well see more mosquitoes this year, this doesn’t necessarily mean we’ll see more related disease.

This depends on a range of other factors, including local wildlife, essential to the life cycle of disease-transmitting mosquitoes.

What is La Niña?

La Niña is a phase of the El Niño-Southern Oscillation, a pattern of ocean and atmospheric circulations over the Pacific Ocean.

While El Niño is generally associated with hot and dry conditions, La Niña is the opposite. La Niña brings slightly cooler but wetter conditions to many parts of Australia. During this phase, northern and eastern Australia are particularly likely to have a wetter spring and summer.

Australia’s most recent significant La Niña events were in 2010-11 and 2011-12.




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Why is wet weather important for mosquitoes?

Mosquitoes lay their eggs on or around stagnant or still water. This could be water in ponds, backyard plant containers, clogged gutters, floodplains or wetlands. Mosquito larvae (or “wrigglers”) hatch and spend the next week or so in the water before emerging as adults and buzzing off to look for blood.

If the water dries up, they die. But the more rain we get, the more opportunities for mosquitoes to multiply.

Mosquito biting a person's hand
Mosquito populations often increase after wet weather.
Cameron Webb/Author provided

Mosquitoes are more than just a nuisance. When they bite, they can transmit viruses or bacteria into our blood to make us sick.

While Australia is free of major outbreaks of internationally significant diseases such as dengue or malaria, every year mosquitoes still cause debilitating diseases.

These include transmission of Ross River virus, Barmah Forest virus and the potentially fatal Murray Valley encephalitis virus.




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What happens when we get more rain?

We’ve know for a long time floods provide plenty of water to boost the abundance of mosquitoes. With more mosquitoes about, there is a higher risk of mosquito-borne disease.

The amount of rainfall each summer is also a key predictor for seasonal outbreaks of mosquito-borne disease, especially Ross River virus.




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Inland regions of Queensland, New South Wales and Victoria, especially within the Murray Darling Basin, are particularly prone to “boom and bust” cycles of mosquitoes and mosquito-borne disease.

In these regions, the El Niño-Southern Oscillation is thought to play an important role in driving the risks of mosquito-borne disease.

The hot and dry conditions of El Niño aren’t typically ideal for mosquitoes.

But historically, major outbreaks of mosquito-borne disease have been associated with extensive inland flooding. This flooding is typically associated with prevailing La Niña conditions.

For instance, outbreaks of Murray Valley encephalitis in the 1950s and 1970s had significant impacts on human health and occurred at a time of moderate-to-strong La Niña events.




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Over the past decade, when La Niña has brought above average rainfall and flooding, there have also been outbreaks of mosquito-borne disease.

These have included:

  • Victoria’s record breaking epidemic of Ross River virus in 2016-17 after extensive inland flooding

  • southeast Queensland’s outbreak of Ross River virus in 2014-15, partly attributed to an increase in mosquitoes associated with freshwater habitats after seasonal rainfall

  • eastern Australia’s major outbreaks of mosquito-borne disease associated with extensive flooding during two record breaking La Niñas between 2010 and 2012. These included Murray Valley encaphalitis and mosquito-borne illness in horses caused by the closely related West Nile virus (Kunjin strain).

We can’t say for certain there will be more disease

History and our understanding of mosquito biology means that with the prospect of more rain, we should expect more mosquitoes. But even when there are floods, predicting outbreaks of mosquito-borne disease isn’t always simple.

This is because of the role wildlife plays in the transmission cycles of Ross River virus and Murray Valley encephalitis virus.




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After the floods come the mosquitoes – but the disease risk is more difficult to predict


In these cases, mosquitoes don’t hatch out of the floodwaters carrying viruses, ready to bite humans. These mosquitoes first have to bite wildlife, which is where they pick up the virus. Then, they bite humans.

So how local animals, such as kangaroos, wallabies and water birds, respond to rainfall and flooding will play a role in determining the risk of mosquito-borne disease. In some cases, flooding of inland wetlands can see an explosion in local water bird populations.

How can we reduce the risks?

There isn’t much we can do to change the weather but we can take steps to reduce the impacts of mosquitoes.

Wearing insect repellent when outdoors will help reduce your chance of mosquito bites. But it’s also important to tip out, cover up, or throw away any water-holding containers in our backyard, at least once a week.

Local authorities in many parts of Australia also undertake surveillance of mosquitoes and mosquito-borne pathogens. This provides an early warning of the risk of mosquito-borne disease.




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The Conversation


Cameron Webb, Clinical Associate Professor and Principal Hospital Scientist, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.