April 2017Strategy

Ticks, mosquitoes & vector-borne disease: a new focus for Eco-Justice organizing?

In some communities, environmental justice activists organizing around climate change focus on childhood asthma associated with pollution from coal-burning power plants. It's an indirect approach, but for parents of small children living near electric power stations, it's a much more immediate way of talking about the risks of coal consumption than scientific predictions about long-term average temperatures.

Now eco-justice organizers may have another tool for talking to the public about climate risks, if we can use it skillfully.  According to a May 1 report published by Center for Disease Control and Prevention (CDC), reported cases of tick-borne diseases across the US more than doubled between 2004 and 2016, from about 22,000 cases to about 48,000 annually.

Over the same period -- which coincided with some of the warmest global average temperatures ever recorded -- total reported cases of vector-borne diseases carried by ticks, mosquitoes and fleas in the U.S. annually more than tripled.  Nine new vector-borne diseases never previously been reported in the U.S. also made their first appearances in the country.  And according to the CDC, the real incidence of people contracting Lyme disease, West Nile Virus and many other diseases carried by ticks and mosquitoes is probably far higher than the reported rates.

The scale of increase of these diseases in the US population and their high-probability relationship to accelerating climate change broadens the constituencies that are at risk and ripening for organizing on climate issues. And, as we'll see below, the risks range across social classes and may aid in uniting those classes around these organizing opportunities.

Many of the 16 vector-borne diseases the CDC monitors are hard to diagnose, so doctors are likely failing to report many cases to public health authorities. In addition, those who contract some vector-borne illnesses (including West Nile Virus and Zika Virus, for example) often show very mild symptoms, although these same illnesses can also be extremely serious or even fatal in some individuals.

Accordingly, the CDC's report noted that "Recent data from clinical and laboratory diagnoses estimate that Lyme disease infects approximately 300,000 Americans yearly, eight- to tenfold more than the number reported."  In the case of West Nile Virus, the report said, there are likely 30 to 70 times as many cases of the mild, "nonneuroinvasive" kind in the U.S. as cases of the more severe, potentially brain-damaging variety.

The CDC did not officially link rising rates of vector-borne diseases to climate change, possibly because the Trump administration discourages government agencies from even mentioning the climate issue. Â Instead, in a May 1 news release, the CDC stated that the rising incidence of vector-borne diseases is "likely due to many factors."

For example, "Mosquitoes and ticks and the germs they spread are increasing in number and moving into new areas. As a result, more people are at risk for infection. Overseas travel and commerce are more common than ever before. A traveler can be infected with a mosquito-borne disease, like Zika, in one country, and then unknowingly transport it home. Finally, new germs spread by mosquito and tick bites have been discovered."

But at a May 2 news conference, the study's lead author Dr. Lyle Peterson, in response to questions from reporters, acknowledged that when it comes to vector-borne diseases spreading into new areas: "we know that temperature is very important … if you increase temperatures in general, what will happen is that the tick populations could move further north, expanding their range. As well as increasing the length of tick season, which puts more people at risk for a longer period of time."

Responding to a follow-up question from NPR reporter Allison Aubrey, Dr. Peterson added:  "What I can say is that any of these diseases are very sensitive to temperatures. And so when there is increasing temperatures, it [sic] promotes several things. One is the mosquito-borne diseases tend to get worse during heat waves. West Nile Virus major outbreaks in the United States have all happened during heat waves. So temperatures tend to make mosquitos more infectious and infectious faster thus promoting outbreaks."

Various mainstream media outlets and advocacy groups, even before the publication of the CDC study, have been much more direct in linking rising vector-borne disease rates to a warming climate than Dr. Peterson chose to be last month.

Last year, for example, the corporate-backed advocacy organization "Vital Strategies," in a report titled Climate change will mean more vector-borne disease in cities: How public health can respond, noted that "Zika virus is primarily transmitted by the Aedes aegypti mosquito.  Local climate affects not only mosquito survival, reproduction rate and activity but also reproduction of the Zika virus within the [mosquitoes]… In a given location, climate change can also lengthen the mosquito season."

The American Public Health Association made roughly the same point in November 2010, in an online article in The Nation's Health called "Vector-borne diseases growing as threats to U.S. public health: Climate change, travel linked to illness." More recently, Earth Island Journal, in its May 2018 issue, carried an excerpt from a new book by investigative reporter Mary Beth Pfeiffer called Lyme: The First Epidemic of Climate Change.

In that excerpt Pfeiffer stated: "This spreading toll of tick-borne disease is not a random act of nature. By virtue of the developed world's lifestyle and influence — the cars, the suburban tracts and carved-up forests, the diminished biodiversity, the emissions and airplanes -- we have paved the way for the first global epidemic abetted by climate change. Warming may not have caused this scourge, but it most certainly is enabling it."

South Florida journalist Kate Stein, in the May 28 issue of the online Jesuit publication America, has cited the results of the CDC study to argue that the spread of mosquito-borne diseases like Zika, dengue fever, the exceedingly painful chikungunya disease, West Nile Virus and yellow fever illustrate another way in which climate change is particularly hurting the poor, both in the U.S. and around the world.

In an article titled "As the Earth warms, mosquitoes become a social justice issue," Stein quoted a senior director of the U.S. Catholic Health Association, Julie Trocchio, to the effect that "People who are the least responsible for this problem [of climate change] are the people who are bearing the burden, whether it's in this country or third-world countries."

That's an argument supported by the World Health Organization (WHO) and other commenters on global trends in public health.

As noted by the authors of a 2015 article in Philosophical Transactions B of the Royal Society in London, "WHO estimates that one-sixth of the illness and disability suffered worldwide is owing to vector-borne diseases, with more than half of the world's population currently at risk. Every year, more than one billion people are infected, and more than one million people die from vector-borne diseases."

The health burden, the authors continue, "is greatest for the poorest populations. For example, the per capita mortality rate from vector-borne diseases is almost 300 times greater in developing nations than in developed regions," for a variety of reasons.

But both in poor developing nations and in richer developed ones, "vector-borne disease risks are typically much greater for poor individuals within any population owing to poorer environmental and social conditions (e.g. lower-quality housing situated closer to vector-breeding sites), and lack of access to preventive and curative health interventions and services."

Looking at the health risks associated with mosquito bites in Baltimore, Washington Post science reporter Chris Mooney in 2016 found that researchers studying the issue found that in peak mosquito season in late summer, "The number of mature, biting Asian tiger mosquitoes that can be found in Baltimore's poorer Harlem Park and Franklin Square neighborhoods is roughly three times the number in wealthier areas of town."

Researchers also found that another mosquito species, Culex pipiens, which can carry West Nile virus, "is more common in hard-hit urban areas and particularly has seemed to thrive in discarded-tire 'habitats' in Baltimore."

The research cited in Mooney's article suggests that poor garbage collection and the presence of discarded bottles and other trash that provide places for water to collect in inner-city alleys -- thus facilitating mosquito breeding -- may account for the greater risks that local residents face.

In an article published by the National Academy of Sciences in 2011, "Neglected Infections of Poverty in the United States of America," George Washington University researcher Peter J. Hotez identified at least one mosquito-borne disease, dengue, as among a large group of "chronic and debilitating parasitic, bacterial and congenital infections" that disproportionately affect poor and under-represented minority U.S. populations.

The flooding of rural Louisiana by Hurricane Katrina in 2005, Hotez wrote, has exposed low-income black residents of the Louisiana Delta country to significantly higher risks of getting dengue.  In lower-income, largely Latino communities along the U.S.-Mexico border, meanwhile, the risks of contracting dengue from disease-carrying mosquitoes are being elevated by "Poor housing without plumbing, air condition or window screens," and some communities by inadequate street drainage.

According to the May 1 CDC report, however, reported cases of dengue, Zika virus and chikungunya disease were overwhelmingly from Puerto Rico, American Samoa and the U.S. Virgin Islands, "where they were periodically epidemic," during the 2004-2016 period.

Unlike tick-borne diseases such as Lyme disease, babesiosis and anaplasmosis (the last two of which are sometimes fatal), mosquito-borne diseases are far more likely to be transmitted from infected individual to individual by mosquitoes, and their reported incidence therefore comes in waves of epidemics of transmission, rather than building gradually.  Thus in Puerto Rico, unfortunately, some 36,000 cases of mosquito-borne Zika virus were reported in 2016, while there also was "limited" local transmission of the disease in Florida and Texas.

Organizing Implications

For eco-socialists and other environmental justice advocates, the problem of climate change and the warmer and wetter weather it can cause also triggering increased risks of vector-borne disease offers a complex challenge, but one with several possible organizing handles.

In some parts of New England, the northern Atlantic Coast and the upper Midwest, relatively affluent suburban communities are significantly at risk from Lyme disease and the ticks that carry it; however, in many poor inner-city neighborhoods and along the Mexican border and in Puerto Rico, dengue fever, Zika and other diseases transmitted by mosquitoes are more of a problem for low-income communities of color.

Arguably, this could mean that eco-justice activists can eventually bring together both white, middle-class suburbanites and lower-income urban communities of color to address vector-borne diseases and the climate conditions that make them more common. Also, in uniting these different constituencies around climate change and vector-borne illness, skillful eco-justice advocates might even raise public awareness of the much greater risks that mosquitoes and ticks pose for as many as 1 billion poor people living in the global South.

As suggested by some of the research cited above, one potential domestic target for activists organizing around climate and vector-borne disease is poor housing and inadequate garbage collection in low-income neighborhoods; another is inadequate access to medical care for the poor.  Other practical organizing opportunities at the local level may exist as well: for example, a recent paper published by conservative Liberty University, of all places, notes that in Savannah, GA, where lower-income black residents in urban neighborhoods show more concern about mosquito-borne disease than white suburbanites, existing attempts by local officials to inform urban residents of mosquito-control methods by Internet are inadequate: probably more personal contacts between the health agencies and low-income neighborhoods is required.

Finally, the risks of growing vector-borne disease transmission also raise important political questions about adequate funding for state and local public health agencies. One of the CDC's findings is that "Preventing and responding to vector borne disease outbreaks will require additional capacity at state and local levels for tracking, diagnosing, and reporting cases; controlling vectors; and preventing transmission."

The report continued: "In the face of increasing incidence and threat from novel pathogens, the burden on local and state public health departments has increased." National networks of vector-control officials are "essential to support threat reduction and counter outbreaks," the CDC noted, "yet in a recent national survey 84% of 1,083 local mosquito control organizations reported lacking one or more of five core vector control competencies."

Clearly, the health care agencies need more support, and possibly eco-justice organizers might want to organize campaigns to demand that politicians provide it.

For democratic socialists already engaged in organizing around health care issues, and for others primarily working on climate change policies, it may seem like a political stretch to consider how hotter and wetter summers will affect tick and mosquito populations and the diseases they can carry.  But as areas of the country exposed to Lyme disease, West Nile, Zika and other vector-borne diseases continue expanding, this may be an issue that socialists cannot afford to ignore.

Additional Resources on Climate Change and Vector-Borne Disease

For further practical advice on avoiding ticks and mosquitoes, Washington Socialist readers may want to look at the CDC's advice at , on reducing exposures to disease-carrying mosquitoes, and also at the CDC web page on reducing exposures to ticks.

The District of Columbia Department of Health has a web page on avoiding mosquito bites at  Another DCDOH web page discusses mosquito repellents.

Maryland's Department of Health has a web page on Lyme disease, its prevention and its diagnosis. And the main Maryland government web page on mosquito-related diseases is located within the state Department of Agriculture.

In Virginia, the state Department of Health has a web site on vector-borne diseases, with separate links to pages on mosquito-borne diseases and tick-borne diseases.

As noted above, insect repellents containing DEET are considered superior to the available alternatives, although some sites report that repellents based on picaridin and lemon eucalyptus oil [OLE] are acceptable substitutes.

In a June 2017 article on repellents, Consumer Reports recommends DEET, picaridin and OLE products, and to a lesser extent repellents containing the synthetic chemicals IR3534 and 2-Undecane, as opposed to repellents based on other techniques and chemicals.

In an update in May 2018, CR notes that partly as a result of the recent global panic around exposures of pregnant women to Zika virus, there are now more than 25,000 different mosquito- and tick-control products on the market, including many more "natural" and seemingly more attractive products than DEET formulations. But CR found that nearly all alternatives to DEET, picaridin and OLE have only short-lived effectiveness, at best, while some seem virtually worthless.

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