Are the Solutions to West Nile Virus Even Worse Than the Virus Itself?

Charleston County is Taking Measures to Combat West Nile Virus.
Could They Actually be Worse for Our Health?

By Aidan Hylen and Blake C. Scott

In August of this year, the South Carolina Department of Public Health notified Charleston County Mosquito Control (CCMC) of several confirmed cases of West Nile virus (WNV) in Charleston County. According to the CDC, 80% of individuals infected with West Nile virus feel no symptoms, and 20% experience mild flu-like symptoms. Very rarely does WNV result in serious illness. None of the cases in Charleston County have resulted in individuals being hospitalized.

Still, CCMC announced that they would be “taking additional measures to reduce adult mosquito populations,” including the aerial spraying of an insecticide called Trumpet EC. Trumpet’s active ingredient is Naled, which belongs to a group of chemicals known as organophosphates. Peer-reviewed scientific studies in Nature and other high-profile publications show that this group of chemical pesticides are toxic to both wildlife and humans, affecting neurological development, reproduction, and general ecosystem health.

So how did this stuff become so widely used?

In the 1940’s and 1950’s, DDT was the most popular insecticide in the United States. It was thought to be a “miracle chemical” for its effectiveness in killing mosquitoes that could transmit malaria and other diseases. It was used everywhere, from cities to farms, for pest control. However, Rachel Carson’s seminal book Silent Spring, published in 1962, sounded the alarm about the ways in which DDT was poisoning both birds and humans. In 1972, the newly-formed Environmental Protection Agency banned the use of DDT in the United States due to widespread public pressure. Perhaps the most important lesson learned from that situation was the need to adhere to the precautionary principle, which states that when we are unsure of the effects of a technology on our health or environment, we should exercise caution in implementing it.

As a result of DDT’s ban, chemical companies quickly switched to organophosphates as insecticides. However, decades of peer-reviewed scientific research suggests that organophosphates pose a serious risk to the health of humans and our environment. For example, exposure to the organophosphate Chlorpyrifos can damage the development of children and is tied to neurological disorders such as autism, ADHD, memory loss, and decreased IQ. It can also permanently damage DNA, putting individuals at an increased risk of cancer. What’s more, as wildlife eat mosquitos or other insects exposed to these chemicals, their concentration can biomagnify up the food chain, meaning that entire ecosystems are affected.

All of these health risks led the European Union to ban the use of Chlorpyrifos in pesticides in 2019, saying that “no safe exposure level” could be identified for the substance. The EPA followed suit, banning Chlorpyrifos from being used in agriculture in 2021, but the ban was later reversed due to pressure and legal challenges from chemical manufacturers. Similarly, the EPA has acknowledged human health risks from the organophosphate Naled “immediately following aerial application for wide-area public health mosquito control.”

It is certainly valid to have concerns about the potential spread of West Nile virus. But spraying insecticides that have long-lasting effects on our health and our coastal environment is not the best way to alleviate those concerns.

We must change our ways, if we are to avoid another silent spring.

Aidan Hylen is a student at the College of Charleston, majoring in Environmental and Sustainability Studies and Political Science. He is also President of the CofC club, Students of the Marsh. Blake C. Scott is a professor of international and environmental studies at the College.

Sources

Charleston County press release about increased spraying following West Nile Virus detection:

https://www.charlestoncounty.gov/news/2026/charleston-county-mosquito-control-increases-treatment-surveillance-following-west-nile-virus-detection.pdf?v=701

EU Bans Chropyrifos-methyl for potential human health risks:

https://www.env-health.org/victory-for-health-european-general-court-upholds-ban-for-chlorpyrifos-methyl/

https://food.ec.europa.eu/plants/pesticides/approval-active-substances-safeners-and-synergists/renewal-approval/chlorpyrifos-chlorpyrifos-methyl_en

Review of health risks of Chropyrifos-methyl:

https://pmc.ncbi.nlm.nih.gov/articles/PMC9566616/