Mice exposed to fracking chemicals during pregnancy were less able to fend off diseases; scientists say this could have major implications for people near oil and gas sites
Chemicals commonly found in groundwater near fracked oil and gas wells appear to impair the proper functioning of the immune system, according to a lab study released today.
The study, published today in the journal Toxicological Sciences, is the first to find a link between fracking chemicals and immune system problems and suggests that baby girls born to mothers near fracking wells may not fight diseases later in life as well as they could have with a pollution-free pregnancy.
"This is a really important study, especially since the work started with the idea of identifying what's out there in the environment, how much people are exposed to," Andrea Gore, a professor of pharmacology and toxicology in the College of Pharmacy at the University of Texas at Austin, told EHN.
"So it's all based on this model that has been determined by a real world situation," said Gore, who was not involved in the study.
The implications are far-reaching: More than 17 million people in the U.S live within a mile of an oil or gas well. Hydraulic fractured wells now account for about half of U.S. oil and two-thirds of the nation's natural gas, according to the U.S. Energy Information Administration.
Fracking, short for hydraulic fracturing, is a method of drilling where millions of gallons of water and chemicals are pumped underground at high pressures to fracture shale or coal bed layers to release otherwise unreachable oil and gas deposits. The chemicals used in the process remain proprietary, however, industry has reported more than 1,000 chemicals are used in fracked oil and gas wells—and researchers have found more than 200 of these compounds in wastewater near extraction.
The researchers exposed mostly female mice in their mothers' womb to the chemical mixture at levels commonly found near fracking sites. Exposed mice had "abnormal responses" to diseases when they were older—specifically an allergic disease, a certain type of flu, and a disease similar to multiple sclerosis.
"The mice whose moms drank water containing the mixture had faster disease onset and more severe disease," lead author Paige Lawrence told EHN in a phone interview. Lawrence is a researcher and chair of Environmental Medicine at the University of Rochester Medical Center.
Some of the observed changes were subtle — "such as alterations in the number or percentage of certain cell types, whereas other changes were more manifest, such as advancement in the onset and severity of disease," the authors wrote.
Lawrence said human and mice immune systems are "more similar than they are different."
"This provides information as to what to look for in people," she said.
It's not entirely clear how the mixture altered the mouse immune system, but Lawrence said the chemicals may be altering pathways that control the immune cells that would fight off diseases. Some of the compounds in the mixture—benzene and styrene—are considered toxic to mammals' immune system.
Susan Nagel, a researcher and associate professor of obstetrics, gynecology and women's health at the University of Missouri School of Medicine and study co-author, said the 23 chemicals they use are known endocrine disruptors, meaning they interfere with the proper functioning of hormones.
Properly functioning hormones are crucial for immune system development.
There's probably "some overlap of chemicals that perturb the endocrine system, some that perturb the immune system and probably some that do both," Gore said.
Female mice had more severe changes to their immune systems and abilities to fight off disease. "Immune responses of males and females are inherently different, and ... sex affects the timing, magnitude or penetrance of many diseases," the authors wrote, but cautioned that this study alone doesn't conclude that females are more sensitive to fracking chemicals than males.
The study is just the latest concern for people near fracking sites. Previous studies have found associations between living near fracking sites and birth defects, prostate and breast cancer, asthma, and acute lymphocytic leukemia.
Over the past decade the U.S. Environmental Protection Agency has identified dozens of chemicals used in fracking as health hazards, according to a report from the Partnership for Policy Integrity and Earthworks. However the report found the agency allowed the chemicals to be made and used, and hasn't disclosed the chemicals to the public.
The EPA would not comment on the new study — a spokesperson said the agency is reviewing it.
“Fracking and building pipelines in order to create more poisonous plastic is ruining people’s lives.”
Jill Hunkler, an Ohio resident who considers herself a “fracking refugee,” is telling her family’s story at the global plastics treaty negotiations in Ottawa this week, where negotiators from about 175 countries are working to advance a treaty to address global plastic pollution.
“I was forced to leave my home that I built with my own hands,” she told Environmental Health News. “I lived in Somerset Township, Ohio, where my sister, my mom and I had 13 acres of land and we had spent years building homes on it that we loved, but then 78 fracking well pads were built within five miles of our home.”
Air pollution from the fracking operations sickened her and her family, Hunkler said, and they experienced symptoms like headaches, nausea, rashes, body aches and difficulty breathing that they hadn’t experienced before the wells were drilled. The family tried to get help from regulators, but after years of suffering with little action, they opted to move.
Her family moved to another property, she said. “But eventually fracking showed up there too, and I moved again to try and escape it. So now I’m twice a fracking refugee.”
More than 99% of plastic is made from fossil fuels, and as the world transitions to renewable energy, fossil fuel companies — particularly those invested in fracking — are driving a new plastics boom to stay profitable. For example, in the Ohio River Valley, where Hunkler is from, Shell recently began operations at its massive Pennsylvania plastics plant that converts fracked ethane gas into plastic pellets, many of which are used to create single-use plastic products like bags and packaging.
Since starting up in 2022, Shell’s Pennsylvania plastics plant has been fined millions of dollars for violating clean air laws and is being sued by environmental advocacy groups over potential health impacts from harmful emissions. Last week, Pennsylvania’s Attorney General Michelle Henry also announced charges against Shell for violating Pennsylvania’s Clean Streams laws with industrial waste during construction of the pipelines that bring ethane feedstock from fracked natural gas to the plastics plant. Concerns about pollution from the plant have also caused families to move away from the region.
After becoming a fracking refugee, Hunkler spent eight years fighting to stop a similar plastics plant from being built near her home in Ohio — a project that has been put on hold indefinitely.
“When people think about the health impacts of plastics they tend to think about harmful microplastics in our bodies, which is really important, but it’s also important to look at the devastating public health impacts all the way down the supply chain” Hunkler said. “Fracking and building pipelines in order to create more poisonous plastic is ruining people’s lives.”
Tensions at the plastic pollution treaty talks
Jill Hunkler (right) and Anaïs Peterson (left) hold a banner during a march in Ottawa organized by the Break Free From Plastic coalition
Photo by Diane Peterson
If the current trajectory for the plastics industry continues unabated, plastic manufacturing is estimated to account for more than a third of the growth in oil demand by 2030 and nearly half by 2050—ahead of trucks, aviation, and shipping, according to the International Energy Agency.
The stated goal of the global plastics treaty is to end plastic pollution by 2040. Hunkler, like many other activists, believe this goal won’t be achieved unless plastic production stops. They are supporting a version of the plastic treaty supported by a group of “High Ambition” countries that includes slowing down plastic production via bans, restrictions or caps.
"It’s important to look at the devastating public health impacts all the way down the supply chain" – Jill Hunkler, an Ohio resident who considers herself a “fracking refugee.”
Meanwhile, plastic industry lobbyists – also attending the negotiations in Ottawa – are promoting plastic’s beneficial uses, such as medical products and reducing food waste. The plastics industry, alongside a coalition of mostly fossil-fuel-producing countries, are pushing “chemical recycling” as a solution to plastic pollution, but environmental advocates say the process is energy-intensive, creates toxic air and water pollution, and fails to actually reduce plastic waste.
It has also proven difficult to profit from chemical recycling operations — none of the approximately ten operational plants in the US are currently operating at full capacity, according to a report from the advocacy group Beyond Plastic. This month a chemical recycling plant in Oregon was shuttered, and a proposed plant in Pennsylvania was canceled amid concerns about the efficacy and feasibility of chemical recycling.
“I hope sharing my story will help the negotiators in Ottawa recognize that fracking and extracting fossil fuels to keep making more plastic is toxic,” Hunkler said. “With the exception of the small amount of plastic that’s needed for medical and other essential uses, we do not need plastic to function as a society. It’s a relatively new product on the planet, and the convenience of it is not worth jeopardizing the health of our children and future generations.”
CAMERON PARISH, La. — Late into the night, John Allaire watches the facility next to his home shoot 300-foot flares from stacks.
He lives within eyesight of southwest Louisiana’s salty shores, where, for decades, he’s witnessed nearly 200 feet of land between it and his property line disappear into the sea. Two-thirds of the land was rebuilt to aid the oil and gas industry’s LNG expansion. LNG — shorthand for liquified natural gas – is natural gas that's cooled to liquid form for easier storage or transport; it equates to 1/600th the volume of natural gas in a gaseous state. It’s used to generate electricity, or fuel stove tops and home heaters, and in industrial processes like manufacturing fertilizer.
In the U.S., at least 30 new LNG terminal facilities have been constructed or proposed since 2016, according to the
Oil and Gas Watch project. Louisiana and Texas’ Gulf Coast, where five facilities are already operating, will host roughly two-thirds of the new LNG terminals – meaning at least 22 Gulf Coast LNG facilities are currently under construction, were recently approved to break ground or are under further regulatory review.
Although the U.S. didn’t ship LNG until 2016, when a freight tanker left, a few miles from where Cameron Parish’s LNG plants are today, last year the country became the global leader in LNG production and export volume, leapfrogging exporters like Qatar and Australia. The
EIA’s most recent annual outlook estimated that between the current year and 2050, U.S. LNG exports will increase by 152%.
Allaire, 68, watches how saltwater collects where rainwater once fed the area’s diminishing coastal wetlands. “We still come down here with the kids and set out the fishing rods. It's not as nice as it used to be,” he told
Environmental Health News (EHN).
That intimacy with nature drew Allaire to the area when he purchased 311 acres in 1998. An environmental engineer and 30-year oil and gas industry veteran, he helped lead environmental assessments and manage clean-ups, and although retired, he still works part-time as an environmental consultant with major petroleum companies. With a lifetime of oil and gas industry expertise, he’s watched the industry's footprint spread across Louisiana and the Gulf of Mexico’s fragile shores and beyond. Now that the footprints are at the edge of his backyard, Allaire is among a cohort of organizers, residents and fisher-folk in the region mobilizing to stop LNG facility construction. For him, the industry’s expansion usurps the right-or-wrong ethics he carried across his consulting career. For anglers, oil and gas infrastructure has destroyed fishing grounds and prevented smaller vessels from accessing the seafood-rich waters of the Calcasieu River.
From the view of Allaire’s white pickup truck as he drives across his property to the ocean’s shore, he points to where a new LNG facility will replace marshlands. Commonwealth LNG intends to clear the land of trees and then backfill the remaining low-lying field.
“You see what’s happening with the environment,” Allaire said. “When the facts change, I got to change my mind about what we’re doing.”
Community bands together
John Allaire, left, purchased 311 acres in Cameron Parish in 1998, and has watched the oil and gas industry's footprint spread to his property.
Credit: John Allaire
During an Earth Day rally in April, community members gathered in the urban center of Lake Charles to demand local oil and gas industries help deliver a safer, healthier future for all. In between live acts by artists performing south Louisiana’s quintessential zydeco musical style, speakers like James Hiatt, a Calcasieu Parish native with ties to Cameron Parish and a Healthy Gulf organizer, and RISE St. James organizer Sharon Lavigne, who’s fighting against LNG development in rural Plaquemines Parish near the city of New Orleans, asked the nearly 100 in attendance to imagine a day in which the skyline isn’t dotted by oil and gas infrastructure.
Not long ago, it was hard to imagine an Earth Day rally in southwest Louisiana at all. For decades, the area has been decorated with fossil fuel infrastructure. Sunsets on some days are highlighted by the chemicals in the air; at night, thousands of facilities’ lights dot the dark sky.
“It takes a lot of balls for people to start speaking up,” Shreyas Vasudevan, a campaign researcher with the Louisiana Bucket Brigade, told EHN in the days after the rally. In a region with its history and economy intertwined with oil and gas production, “you can get a lot of social criticism – or ostracization, as well – even threats to your life.”
Many are involved in local, regional and national advocacy groups, including the Louisiana Bucket Brigade, Healthy Gulf, the Sierra Club, the Natural Resources Defense Council, the Turtle Island Restoration Network, the Center for Biological Diversity and the National Audubon Society.
“You see what’s happening with the environment,” Allaire said. “When the facts change, I got to change my mind about what we’re doing.” - John Allaire, environmental engineer and 30-year oil and gas industry veteran
But environmental organizers are fighting a multi-billion-dollar industry with federal and state winds at its back. And LNG’s federal support is coupled with existing state initiatives.
Under outgoing Louisiana Gov. John Bel Edwards — a term-limited Democrat — the state pledged a goal of reaching net-zero greenhouse emissions by 2050. Natural gas, which the LNG industry markets as a cleaner-burning alternative, is cited as one of the state’s solutions. Louisiana is the only state that produces a majority of its carbon emissions through fossil fuels refining industries, like LNG, rather than energy production or transportation. Governor Edwards’ office did not return EHN’s request for comment.
This accommodating attitude towards oil and gas industries has resulted in a workforce that’s trained to work in LNG refining facilities across much of the rural Gulf region, said Steven Miles, a lawyer at Baker Botts LLP and a fellow at the Baker Institute’s Center on Energy Studies. Simultaneously, anti-industrialization pushback is lacking. It’s good news for industries like LNG.
“The bad news,” Miles added. “[LNG facilities] are all being jammed in the same areas.”
One rallying cry for opponents is local health. The Environmental Integrity Project found that LNG export terminals emit chemicals like carbon monoxide –potentially deadly– and sulfur dioxide, of which the American Lung Association says long-term exposure can lead to heart disease, cancer, and damage to internal or female reproductive organs.
An analysis of emissions monitoring reports by the advocacy group the Louisiana Bucket Brigade found that Venture Global’s existing Calcasieu Pass facility had more than 2,000 permit violations.That includes exceeding the permit’s authorized air emissions limit to release nitrogen oxides, carbon monoxide, particulate matter and volatile organic compounds 286 out of its first 343 days of operation.
The Marvel Crane, the first liquid natural gas carrier to transport natural gas from the Southwest Louisiana LNG facility, transits a channel in Hackberry, Louisiana, May 28, 2019.
“This is just one facility,” at a time when three more facilities have been proposed in the region and state, Vasudevan said. Venture Global’s operational LNG facility — also known as Calcasieu Pass — “is much smaller than the other facility they’ve proposed.”
In an area that experienced 18 feet of storm surge during Hurricane Laura in 2020 — and just weeks later, struck by Hurricane Delta — Venture Global is planning to build a second export terminal Known as “CP2,” it’s the largest of the roughly two dozen proposed Gulf LNG export terminals, and a key focal point for the region’s local organizing effort.
Residents “don’t really want LNG as much as they want Cameron [Parish] from 1990 back,” Hiatt told EHN of locals’ nostalgia for a community before storms like Rita in 2005 brought up to 15 feet of storm surge, only for Laura to repeat the damage in 2020. Throughout that time, the parish’s population dipped from roughly 10,000 to 5,000. “But the wolf knocking at the door is LNG. Folks in Cameron think that's going to bring back community, bring back the schools, bring back this time before we had all these storms — when Cameron was pretty prosperous.”
“Clearly,” for the oil and gas industry, “the idea is to transform what was once the center of commercial fishing in Louisiana to gas exports,” Cindy Robertson, an environmental activist in southwest Louisiana, told EHN.
Helping fishers’ impacted by LNG is about “actual survival of this unique culture,” Cooke said.
In a measure of organizers’ success, she pointed to a recent permit hearing for Venture Global’s CP2 proposal. Regionally, it’s the only project that’s received an environmental permit, but not its export permit, which remains under federal review. At the meeting, some spoke on the company’s behalf. As an organizer, it was a moment of clarity, Cooke explained. Venture Global officials “had obviously done a lot of coaching and organizing and getting people together in Cameron to speak out on their behalf,” Cooke said. “So, in a way, that was bad. But in another way, it shows that we really had an impact.”
“It also shows that we have a lot to do,” Cooke added.
Environmental organizers like Alyssa Portaro describe a sense of fortitude among activists — she and her husband to the region’s nearby town of Vinton near the Texas-Louisiana border. Since the families’ relocation to their farm, Portaro has worked with Cameron Parish fisher-folk.
“I’ve not witnessed ‘community’ anywhere like there is in Louisiana,” Portaro told EHN. But a New Jersey native, she understands the toll environmental pollution has on low-income communities. “This environment, it’s so at risk — and it’s currently getting sacrificed to big industries.”
“People don’t know what we’d do without oil and gas. It comes at a big price,” she added.
Southwest Louisiana’s Cameron Parish is one of the state’s most rural localities. Marine economies were the area’s economic drivers until natural disasters and LNG facilities began pushing locals out, commercial fishers claim.
Credit: Xander Peters for Environmental Health News
Residents “don’t really want LNG as much as they want Cameron [Parish] from 1990 back,” James Hiatt , a Healthy Gulf organizer, told EHN. "But the wolf knocking at the door is LNG."
Credit: Xander Peters for Environmental Health News
For the most part, Cameron Parish’s life and economy has historically taken place at sea. As new LNG facilities are operational or in planning locally, locals claim the community they once knew is nearly unrecognizable.
Credit: Xander Peters for Environmental Health News
A disappearing parish
The stakes are seemingly higher for a region like southwest Louisiana, which is the epicenter of climate change impacts.
In nearly a century, the state has lost roughly 2,000 square miles of land to coastal erosion. In part driving the state’s erosion crisis is the compounding impacts of Mississippi River infrastructure and oil and gas industry activity, such as dredging canals for shipping purposes, according to a March study published in the journal Nature Sustainability. Louisiana’s Coastal Protection and Restoration Authority said Cameron Parish could lose more land than other coastal parishes over the next 50 years. A recent Climate Central report says the parish will be underwater within that time frame.
On top of erosion and sea level rise impacts, in August, 2023, marshland across southwest Louisiana’s Cameron Parish burned. The fires were among at least 600 across the Bayou State this year. Statewide, roughly 60,000 acres burned — a more than six-fold increase of the state’s average acres burned per year in the past decade alone.
But while the blaze avoided coastal Louisiana communities like Cameron Parish, the fires represented a warning coming from a growing chorus of locals across the region — one that’s echoes by the local commercial fishing population, who claimed to have experienced unusually low yields during the same time, according to a statement from a local environmental group. At the site of the Cameron Parish fires are locations for two proposed LNG expansion projects.
"The idea is to transform what was once the center of commercial fishing in Louisiana to gas exports.” - Cindy Robertson, an environmental activist in southwest Louisiana
It was an unusual occurrence for an area that’s more often itself underwater this time of year due to a storm surge from powerful storms. For LNG expansion’s local opposition, it was a red flag.
As the Louisiana Bucket Brigade has noted prior, the confluence of climate change’s raising of sea levels and the construction of LNG export terminals — some are proposed at the size of nearly 700 football fields — are wiping away the marshland folks like Allaire watched wither. Among their fears is that the future facilities won’t be able to withstand the power of another storm like Laura and its storm surge, which wiped away entire communities in 2020.
Amidst these regional climate impacts, LNG infrastructure has shown potential to exacerbate the accumulation of greenhouse gasses that cause global warming. For the most part, LNG is made up of methane — a greenhouse gas that’s more than 80 times more potent than carbon dioxide in the atmosphere. Among the 22 current LNG facility proposals, the advocacy group Sierra Club described a combined climate pollution output that would roughly equal to that of about 440 coal plants.
The climate impacts prompt some of the LNG industry’s uncertainty going forward. It isn’t clear if Asian countries, key importers of U.S. LNG, will “embrace these energy transition issues,” said David Dismuke, an energy consultant and the former executive director of Louisiana State University’s Center for Energy Studies. Likewise, European nations remain skeptical of embracing LNG as a future staple fuel source.
“They really don't want to have to pull the trigger,” Dismukes added, referring to Europe’s hesitation to commit more resources to exporting LNG from the American market. “They don't want to go down that road.”
While there will be a tapering down of natural gas supply, Miles explained, “we’re going to need natural gas for a long time,” as larger battery storage for renewables is still unavailable.
“I'm not one of these futurists that can tell you where we're going to be, but I just don't see everything being extreme,” Dismukes said. “I don't see what we've already built getting stranded and going away, either.”
For now, LNG seems here to stay. From 2012 to 2022,U.S. natural gas demand — the sum of both domestic consumption and gross exports — rose by a whopping 43%, reported the U.S. Energy Information Administration, or EIA. Meanwhile, in oil and gas hotbeds like Louisiana and Texas, natural gas demand grew by 116%.
Throughout 25 years, Allaire has witnessed southwest Louisiana’s land slowly fade, in part driven by the same industrial spread regionally. Near where the front door of his travel trailer sits underneath the aluminum awning, he points to a chenier ridge located near the end of the property. It’s disappearing, he said.
“See the sand washing over, in here?” Allaire says, as he points towards the stretches of his property. “This pond used to go down for a half mile. This is all that's left of it on this side.”
New research shows a few multinational companies, including Philip Morris International and Coca-Cola, are major contributors to global plastic pollution, a study finds.
Researchers identified 56 major companies responsible for half of all plastic waste, with six companies –Altria, Philip Morris International, Coca-Cola, Nestlé, Danone and PepsiCo– producing a quarter of that.
Over five years, the team collected 1,870,000 items of plastic waste across 84 countries.
Companies are making efforts to increase recyclability and reduce virgin plastic use.
Despite corporate initiatives, plastic production and pollution have risen in lockstep, challenging the effectiveness of current recycling efforts.
Key quote:
"The industry likes to put the responsibility on the individual (...) But it’s the brands, it’s their choice for the kinds of packaging [they use] and for embracing this throwaway model of delivering their goods. That’s what’s causing the greatest abundance of trash."
— Marcus Eriksen, plastic pollution expert from The 5 Gyres Institute and co-author of the study.
Why this matters:
Identifying major contributors to plastic pollution allows for greater accountability. Public awareness can lead to pressure on these companies to implement sustainable practices, invest in research and development of alternative materials, and take corporate social responsibility seriously.
Europe grapples with escalating plastic pollution, driven by petrochemical imports from Texas. A recent report by Amnesty International shows how some of these imported petrochemical products are linked to environmental racism, and calls for more stringent rules to restrict the proliferation of polluting plastics.
European shores are increasingly littered with plastic pellets, causing environmental emergencies and threats to marine life.
Petrochemicals linked to human rights abuses in Texas are contaminating Europe's plastic supply, with European companies implicated.
New EU rules and a potential UN plastics treaty aim to tackle the entire lifecycle of plastics, highlighting the need for global accountability in the industry.
Key quote:
"Combined with a tough new UN plastics treaty, the new EU directive could help turn the tide against plastics in Europe – which can’t come soon enough for the continent’s beaches, bottle-blighted rivers, and all those communities suffering at the hands of the plastics and fossil fuel industries."
— Alysha Khambay, report author and researcher at Amnesty International
HOUSTON — En homenaje al Día de la Tierra, EHNe está publicando cartas de estudiantes del octavo grado de YES Prep Northbrook Middle School en el barrio de Spring Branch, Texas, que está en el área de Houston.
Las profesoras de literatura y gramática Cassandra Harper e Yvette Howard incorporaron el medio ambiente en una serie de lecciones en diciembre del año pasado. Cada estudiante realizó sus propias investigaciones para iniciar la redacción de cartas a EHNe sobre sus preocupaciones o esperanzas. Cami Ferrell, reportera de EHNe, visitó el salón de clase para hablar sobre sus propias experiencias reportando en Houston.
La colección de cartas, editadas ligeramente, no representa las opiniones del YES Prep Northbrook o EHN, pero las publicamos para echar un vistazo a las mentes jóvenes y su relación con los problemas medioambientales.
A Department of Energy advisory committee warns that current growth rates in the hydrogen sector are insufficient for meeting 2050 net-zero emission targets.
The National Petroleum Council's report calls for increased policy support to scale hydrogen production and manage natural gas emissions effectively.
Recommendations include extending tax subsidies and boosting infrastructure to facilitate hydrogen industry development and adoption.
Key quote:
" ... in five years or 10 years, the energy status quo is going to be obsolete."
— Jennifer Granholm, Energy Secretary.
Why this matters:
While hydrogen power holds significant promise for helping meet climate goals due to its clean and versatile energy solutions, its growth in the U.S. requires overcoming economic, technological and policy barriers.
Prof. Rachel Lowe emphasizes the need for preparedness as warmer climates allow mosquitoes to inhabit new regions, potentially introducing diseases to immunologically naive populations.
Dengue fever is spreading rapidly; the Asian tiger mosquito is now found in 13 European countries.
Climate-related droughts and floods enhance virus transmission through increased mosquito breeding sites.
If current warming trend continues, the number of people living in place where these vectors thrive is expected to double to 4.7 by 2100.
Key quote:
"Global warming due to climate change means that the disease vectors that carry and spread malaria and dengue [fever] can find a home in more regions, with outbreaks occurring in areas where people are likely to be immunologically naive and public health systems unprepared."
— Rachel Lowe, head of the global health resilience group at the Barcelona Supercomputing Center.
Why this matters:
As global temperatures rise, the habitats suitable for mosquitoes are expanding. This expansion means that more people are at risk of dengue fever as these mosquitoes bring the disease to new areas.
