Mosquito-borne Illnesses Are a Growing Threat in the North Country

By Catherine Wheeler. NCPR St. Lawrence Valley Reporter -

A growing threat is buzzing around the North Country. U.S. Sen. Chuck Schumer, one of the nation's top democrats, is sounding the alarm.

"Typically, a mosquito problem would just be an annoying itch. What we've seen here in St. Lawrence [County] has prompted many warnings with some deadly mosquito-borne illnesses," Schumer said at a press conference in Ogdensburg in September.

In the past few months, Schumer has made two stops in northern New York to underscore alerts from health officials.

Health officials became worried when several horses died from the mosquito-borne illness Eastern Equine Encephalitis (EEE). Then, they got really worried when two people in the Northeast, including a person in Ulster County, NY, died from it. And health officials have been worried for years about West Nile Virus, another mosquito-borne disease that can kill people.

Statewide, the New York State Department of Health posts weekly reports of human and animal cases of West Nile Virus and EEE.

These diseases are rare in humans, but Schumer said our public health system needs to respond.

"We need the federal government to get involved in a more serious way," he said. "We need the feds to step up to track and zap New York's growing mosquito problem."

Climate change and "the growing mosquito problem"

As our climate gets warmer and wetter, invasive mosquitos are moving North, and they can spread diseases that aren't usually found here, said Laura Harrington, an entomologist at Cornell University.

One example is the Asian tiger mosquito, Harrington said. It landed in Texas decades ago and has worked its way to the Northeast. That mosquito is capable of transmitting viruses like Dengue and Zika.

"Mosquitoes have very limited temperature ranges that they can survive in," she said. "What happens, and this is the case with the Asian tiger mosquito, is that it's on the margins of those temperatures where it's getting just a little too cold. It's gradually adapting to those cooler temperatures."

Those mosquitos that survive the cold one season are then breeding generations that can live in even cooler temperatures, Harrington said.

"Having this local adaptation and then having warmer days [and] fewer extremely cold days in the winter when these organisms are overwintering enhances their survival," she said.

New York's Climate Assessment predicts temperatures and precipitation levels will continue to rise. Harrington said that will help all kinds of mosquito populations and the diseases they carry thrive.

"More storms, more rainwater changes that are related to climate change definitely will contribute to increase for some of these pathogens, unfortunately," she said.

There are a couple of other factors that are also helping mosquitos broaden their habitats, Harrington said.

"People can unintentionally create habitats through developments, managing water through storm drains," she said. "That can actually help provide habitats for mosquitoes. And construction sites are really good sites for container-breeding mosquitoes. There are different ways that we're manipulating the land and the environment that can enhance the habitat."

"Track and zap"

There is a way for scientists and communities to track mosquito-borne diseases so they can fight back. It's called surveillance.

"With surveillance, the first thing you do is set up an area, like distribution of our landscape, in order to look for where the mosquitoes are," said Tom Langen, a biologist at Clarkson University.

Surveillance programs allow scientists to figure out what kinds of mosquitos are out there, if they're carrying diseases, and how widespread they are, Langen said.

"When we get them checked, we can say, 'Well, there's a higher prevalence of Triple E here than there,'" he said. "So, if we have that we can say, 'okay, it's everywhere in the county,' or 'everywhere in the North Country', or 'it's localized at certain swampy areas where we might want to target.'"

That means a community could make informed decisions about management strategies, like spraying a particular area that has a lot of infected mosquitos.

Finding the funding

These surveillance programs haven't been a priority in the North Country. But experts say that's going to have to change, as more mosquitoes bring more disease.

"If money and resources weren't an issue, I think every state and every county would have a program like this and it could really save lives," said Laura Harrington, an entomologist at Cornell University.

St. Lawrence County's Public Health Director Erin Streiff said, right now, her office only knows a disease is in the area when a person or an animal, mainly horses, tests positive.

She said surveillance is a better long-term strategy.

"Trends over time matter. And we're looking not only at disease burden in the mosquito pools, but also what species of mosquito may be here, if there are new species coming that weren't here previously, those kinds of things," Streiff said. "So we really need years worth of data to kind of validate that."

But surveillance requires long-term funding.

Senator Chuck Schumer said he recognizes the need for investment. Schumer said he's pushing the feds to approve millions of dollars in funding that could help communities in the North Country start mosquito surveillance programs.

"That's why increasing federal funding is so important because as the climate changes, it shifts the risk of communities. They may not have the resources that they need," he said.

While bureaucracy like that takes time, public health officials say there are things you can do to stay safe now.

Horses can be vaccinated against EEE. And while humans can't, we can cover up while we're outside, wear bug spray, remove standing water where mosquitoes can breed, and wait for winter to come.

NCPR's climate change series is made possible through the generous support of Margot and John Ernst. You can find all the stories on our climate change series at ncpr.org/climate. Reprinted with permission.