By Irene Banos Ruiz
Pediatricians in New Delhi, India, say children's lungs are no longer pink, but black.
Our warming planet is already impacting the health of the world's children and will shape the future of an entire generation if we fail to limit global warming to well below 2 degrees Celsius (35.6°F), the 2019 Lancet Countdown Report on health and climate change shows.
Under current emissions, children born today will live in a 4°C warmer world by the age of 71, the report says.
Extreme weather events are also becoming the new normal in European countries.
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The first three cases of Zika that started in southern France have been confirmed and experts are sounding the alarm that the climate crisis may cause more cases to spread across the continent, as CNN reported.
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- Where Mosquitoes Will Multiply Thanks to Climate Change - CityLab ›
- Zika, dengue, and yellow fever are about to get much worse - Vox ›
- The Link Between the Zika Virus and Climate Change - The Atlantic ›
- Tropical disease outbreaks are growing threat in Europe as ... ›
EcoWatch Daily Newsletter
Every year, around one million people die of mosquito-borne diseases according to the World Health Organization (WHO). This is why mosquitoes are considered one of the deadliest living creatures on the planet — not because they are lethal themselves, but because many of the viruses and parasites they transmit are.
Genetically Modified Mosquitoes<p>The transfer of new genes from GM organisms to wild or domesticated non-GM populations is a key criticism of GM crops like soybean and corn. There are concerns that the introduction of GM genes into non-target species could have <a href="https://www.nature.com/scitable/topicpage/genetically-modified-organisms-gmos-transgenic-crops-and-732/" target="_blank">negative consequences for both human and environmental health</a>.</p><p>Oxitec, a company that spun out of research at Oxford University in the early 2000s, developed and trademarked GM <a href="https://www.oxitec.com/our-technology" target="_blank">Friendly™ mosquitoes</a> (also known as strain OX513A of <em>Aedes aegypti</em>). These male GM mosquitoes have what the company describes as a "self-limiting" gene, which means that when these so-called friendly mosquitoes mate, their offspring inherit the self-limiting gene which is supposed to prevent them surviving into adulthood.</p><p>In theory, when these mosquitoes are released in high numbers, a dramatic reduction in the mosquito population should follow.</p><span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="8d418a7c3cf175000fe60ea35aab2cb5"><iframe lazy-loadable="true" src="https://www.youtube.com/embed/5dRGPsx3tAw?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>
Changes to the Gene Pool<p>According to research published by Oxitec researchers in 2015, field trials involving recurring releases of Friendly™ mosquitoes demonstrated <a href="https://doi.org/10.1371/journal.pntd.0003864" target="_blank">a reduction of nearly 95 percent of target populations in Brazil</a>. In these field trials, experiments were not performed to assess whether GM mosquitoes might persist in the wild.</p><p>A recent study from the Powell lab at Yale University has since confirmed that <a href="https://www.nature.com/articles/s41598-019-49660-6" target="_blank">some of the offspring of the GM mosquitoes didn't succumb to the self-limiting lethal gene and survived to adulthood</a>. They were able to breed with native mosquitoes and thereby introduce some of their genes into the wild population.</p><p>The Yale researchers found that mosquitoes captured at six, 12 and up to 30 months post-release carried DNA from the GM mosquito population, thereby disproving "<a href="https://news.yale.edu/2019/09/10/transgenic-mosquitoes-pass-genes-native-species" target="_blank">the claim that genes from the release strain would not get into the general population because offspring would die</a>."</p><p>It appears that between five and 60 percent of the captured mosquitoes post-release contained genetic sequences inherited from the Friendly™ mosquitoes. Importantly, the number of mosquitoes identified as still containing DNA derived from GM mosquitoes declined between the 12-month and 27-month capture periods specifically, perhaps indicating that the offspring of GM mosquitoes might be less fit in nature after all. This remains to be shown conclusively.</p>
Unknown Potential Impacts<p><span>Meanwhile, the impact of mosquitoes carrying these new genes remains largely unknown. One significant worry is that a new breed of mosquito might emerge that is more difficult to control. These new genes could also potentially alter evolutionary pressures on viruses carried by mosquitoes, like dengue fever, in unpredictable ways. This includes potentially increasing their virulence or changing their host-insect interactions. These are hypothetical risks that have been raised by scientists, and reflect the need for further study.</span><br></p><p>Thus, like GM soybean or corn, there is legitimate concern about the propagation of <a href="http://dx.doi.org/10.5402/2011/369573" target="_blank">new genetic material</a> in wild populations with as yet unknown consequences.</p><p>Field trials involving the release of GM organisms are typically designed to evaluate safety and efficacy, to assess possible impact on food networks, and to ensure that there is no (or minimal) undue harm to the environment or human health. Put simply, field trials are meant to assess potential harms associated with genetic technologies and to provide opportunities to minimize these harms before moving forward with more large-scale releases.</p><p>This raises two important questions: Given that <a href="https://time.com/the-war-against-mosquito/" target="_blank">"around 5 percent or less"</a> of the GM mosquito population was expected to survive, shouldn't Oxitec have made plans to assess the risk of gene transfer to wild populations during their initial trials? And shouldn't the Brazilian government have required such an assessment as part of the regulatory approval process, <a href="https://bch.cbd.int/database/record.shtml?documentid=105833" target="_blank">given their awareness of the risk</a>?</p><p>Instead, with approval from Brazilian authorities, <a href="https://doi.org/10.1111/eea.12618" target="_blank">Oxitec released nearly half a million GM mosquitoes every week into shared environments in Jacobina over a two-year period from 2013 to 2015</a>. This was done without the benefit of adequate risk assessment and without proper public consultation.</p><p>Oxitec reports having used leaflets, social media, carnival parades and community meetings to inform the public of their research. <a href="https://doi.org/10.1080/23299460.2017.1326257" target="_blank">Public education is not the same as public consultation and engagement</a> and, in our view, the people living in the vicinity of this release had more than a right to be informed of the plans. They also had a <a href="https://science.sciencemag.org/content/362/6414/527.summary" target="_blank">right to participate</a> in relevant decision-making.</p><p>On the basis of presumed success in Brazil where mosquito populations were reduced — a consequential <a href="https://www.who.int/bulletin/volumes/94/8/16-020816.pdf" target="_blank">reduction in the prevalence of dengue fever</a> has yet to be demonstrated — plans have been made to extend field trials to other jurisdictions, including <a href="https://www.oxitec.com/florida" target="_blank">the Florida Keys in the U.S</a>.</p><p>To date, public pushback <a href="https://doi.org/10.1038/nbt.3927" target="_blank">has temporarily prevented</a> the release of GM mosquitoes in the Florida Keys. But Oxitec hopes to eventually secure approval from the U.S. Environmental Protection Agency to perform field trials and assess release of a <a href="https://keysweekly.com/42/oxitec-reveals-new-technology-up-for-epa-consideration/" target="_blank">second-generation GM mosquito</a> that causes lethality only in female mosquitoes, as another means to collapse wild populations.</p>
Regulating Genetic Modification<p>In the end, minus the <a href="https://www.sciencemag.org/news/2019/09/study-dna-spread-genetically-modified-mosquitoes-prompts-backlash" target="_blank">hyperbole and somewhat alarmist reporting of the Yale study</a> (the journal is looking into <a href="https://www.genomeweb.com/scan/pushback-mosquito-paper#.XZJv0S2ZNTZ" target="_blank">allegations brought forth by Oxitec of speculative and unsubstantiated claims</a>), the finding that offspring of GM mosquitoes could survive in the wild remains undisputed. This illustrates the importance of careful decision-making and adequate oversight of field trials involving the release of GM organisms. Careful decision-making requires open venues for informed and deliberative public dialogue, engagement and empowerment.<br></p><p>Genetic modification technologies need to be more transparent, as do the scientific processes for evaluating their risks, especially where the rights and needs of affected communities can inform technology development. With more robust and nuanced regulatory processes governing the development and release of GM organisms, it should be possible to benefit from these technologies without harming or disenfranchising the communities that are the intended beneficiaries.</p><p>Mosquito-borne illnesses cause immense human suffering, and we should continue to develop technologies to reduce that suffering. At the same time, we must be equally dedicated to designing scientific processes that are safe, ethical and just.</p>
By Marlene Cimons
For nearly a century, scientists thought that malaria could only spread in places where it is really hot. That's because malaria is spread by a tiny parasite that infects mosquitoes, which then infect humans — and this parasite loves warm weather. In warmer climates, the parasite grows quickly inside the mosquito's body. But in cooler climates, the parasite develops so slowly that the mosquito will die before the it is fully grown.
Aedes albopictus, also known as a tiger mosquito.
Pexels<p>Malaria is a life-threatening illness caused by <em>Plasmodium</em> parasites that are carried by the female <em>Anopheles</em> mosquito, and passed on to humans through her bite. More than 400,000 people died of the disease in 2017, with sub-Saharan Africa bearing the largest brunt of malaria cases — more than 90 percent — according to the <a href="https://www.who.int/en/news-room/fact-sheets/detail/malaria?source=post_page---------------------------" target="_blank">World Health Organization</a>. It is also a problem in parts of South America and South Asia, according to the <a href="https://www.cdc.gov/malaria/malaria_worldwide/impact.html?source=post_page---------------------------" target="_blank">Centers for Disease Control and Prevention</a> (CDC).</p><p>Malaria was eradicated from the United States in 1951, largely due to effective control measures, such as spraying and air conditioning. Today, only around five people a year die of malaria in the United States. Most of those infected with malaria contracted the disease while traveling, according to the <a href="https://www.cdc.gov/malaria/resources/pdf/fsp/cdc_malaria_domestic_unit.pdf?source=post_page---------------------------" target="_blank">CDC</a>. "It is unlikely that developed countries with active detection and prevention programs, such as ours, would ever become areas of active malaria transmission again," Waite said.</p><p>The disease typically begins with fever, chills and headache, but can lead to death if untreated. "I'm not a medical doctor, but anecdotally I've heard it makes people feel pretty miserable — like a bad flu with cyclic fevers," Waite said. It is particularly dangerous for small children and "can lead to coma and death for severe infections," she said.</p>
Cases of malaria by country in 2017.
A mosquito feeding.
Pixabay<p>After the mosquitoes finished dining, the scientists placed them into different incubators, some warm, some cold. They exposed some mosquitoes to fluctuating temperatures — as in nature, where it's cool at night and warm at midday — and others to constant temperatures. They then dissected them and examined their guts and salivary glands, looking for malaria parasites.</p><p>Open an infected mosquito and you will find bags filled with replicating parasites. When these bags burst, the parasites will spill out and find their way to the mosquito's salivary glands. Infected mosquitoes then pass on these parasites to humans when they draw blood. It takes time for the parasites to grow and then make their way to the salivary glands — but not as much time as was previously thought.</p><p>"So, for example, at [64 degrees Fahrenheit] the [earlier] model would predict mosquitoes become infectious at around 56 days, but we found at constant temperatures infectious mosquitoes were found as early as 33 days," Waite said. "With fluctuating temperatures — similar to real world conditions — this was as fast as 27 days. This makes a big difference because mosquitoes don't live forever."</p><p>Thus, if climate change continues to cause cooler regions to get warmer — even just a little bit — mosquitoes will get a jump start toward becoming fully infectious before they die. Waite is counting on that not happening. "I'm hopeful our work will lead to better estimates of malaria spread, and better prevention strategies," she said.</p>
By Nicole Ferox
It's that time of year: Mosquitoes and ticks are out in full force, and so are all the latest bug repellent products claiming to keep them at bay. So what bug repellent ingredients do Environmental Working Group (EWG) scientists recommend for kids? Our top picks are DEET, Picaridin and IR3535. These ingredients have low safety concerns and offer a high level of protection from a variety of biting insects and ticks.
Can I really use DEET? I thought it was dangerous.<p>Yes, DEET is a reasonable choice when used as directed, even for children. Still, after reviewing the evidence, EWG researchers concluded that it is best to use the lowest effective concentration of DEET, even though it's effective and generally safer than is commonly assumed.</p><p>Picaridin is a great alternative to DEET. It effectively repels both mosquitoes and ticks and, compared to other repellents, is less likely to irritate eyes and skin.</p><p>EWG research indicates that, in general, "natural" bug repellent ingredients like castor, cedar, citronella, clove, geraniol, lemongrass, peppermint, rosemary and/or soybean oils are often not the best choice.</p>
How do I know if there’s a risk of insect-borne disease in my area?<p>Ask your pediatrician or check the Centers for Disease Control and Prevention (CDC) maps listed below. If you're traveling internationally, check the CDC website for information about the <a href="https://wwwnc.cdc.gov/travel/page/world-map-areas-with-zika" target="_blank">Zika virus</a>.</p><ul><li><a href="https://www.cdc.gov/westnile/statsmaps/index.html" target="_blank">U.S. Map of Reported Cases of West Nile Virus</a></li><li><a href="https://www.cdc.gov/lyme/stats/maps.html" target="_blank">U.S. Map of Reported Cases of Lyme Disease</a></li><li><a href="https://www.cdc.gov/ticks/geographic_distribution.html" target="_blank">U.S. Maps of Ticks Carrying Lyme Disease</a></li></ul>
More Information<p><a href="https://www.ewg.org/research/ewgs-guide-bug-repellents" target="_blank">EWG's Guide to Bug Repellents</a></p><p><a href="https://www.ewg.org/childrenshealth/22197/ask-ewg-what-s-best-bug-spray-buy-my-kids" target="_blank">Ask EWG: What's the Best Bug Spray to Buy for my Kids?</a></p><p><a href="https://www.cdc.gov/zika/prevention/prevent-mosquito-bites.html" target="_blank">CDC: Protect yourself and your family from mosquito bites</a></p>
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If greenhouse gas emissions continue to rise until 2080, dengue fever could spread through much of the southeastern U.S. by 2050.
Arachnophobes beware. A shoreline by the Greek town of Aitoliko has been swamped by a mass of mating spiders and 1,000 feet of their cobwebs.
Earlier this week, a local named Giannis Giannakopoulos uploaded a YouTube video and posted several pictures of the spectacle on his Facebook page, showing shrubs, palm fronds and other greenery completely veiled by spider webs.
The research, published Wednesday in the journal Biology Letters, is the first to show that bits of plastic can be transferred between a mosquito's life stages that use different habitats.
By Carla Burns
Experts predict mosquito and tick bites and subsequent infections will continue to rise as warmer climates expand insect habitats and populations. The Centers for Disease Control and Prevention warns that pest-borne diseases are "a large and growing public health problem in the United States." Cases of diseases from mosquito, tick and flea bites more than tripled in the U.S. from 2004 to 2016.
The number of days each year when mosquito-borne illnesses are more likely to spread is rising as average temperatures soar across the U.S., according to a new analysis.
Climate Central examined 244 cities across the country for its analysis, finding that 94 percent are experiencing more "disease danger days"—days with temperatures between 61 degrees and 93 degrees F, optimal conditions for transmission of diseases like West Nile and other vector-borne diseases—than they were in 1970.