
To be fair, that was the answer from the Magic 8 Ball, the experts are much less certain. We have however, been off to a really good start with few confirmed West Nile Virus-infected mosquitoes and nights out haven’t been nearly as painful as in years past. The question now is, will it last?
Last summer Pennsylvania was facing a mosquito crisis. The rain had been nearly nonstop and the state was in the middle of the worst occurrence of West Nile Virus (WNV) in 15 years. During the mosquito season, which lasts from June to October, state testers recorded 4680 WNV positives. By the end of the season 72 human cases would be reported and three deaths blamed on the virus.
By the end of August there would be nearly 4000 WNV positives reported by the state including 18 human cases. By contrast, through the same period this year we have seen just 287 recorded positives including eight in the Borough with no human cases reported so far.
Last year, I was applying bug spray every time I stepped out of the house and this year, I haven’t broken it out much at all. That’s not to say there are no bugs, I have several itchy red bumps, evidence of last night’s evening out without protection, but overall it’s been manageable.
So, what changed?
The Borough’s Biologic Larvicide Program
Earlier this summer I met with Margaret Hudgings and Nathaniel Smith, the leaders behind West Chester’s Don’t Spray Me! group.
“We got a call this morning about a child size swimming pool full of water,” said Hudgings as we settled around the wooden table in the kitchen of her borough home. “I contacted the Borough and they are sending someone over today.”
“We had a 97 percent sign rate. No one wants to be sprayed.”
-Margaret Hudgings, co-founder Don’t Spray Me
Don’t Spray Me! started in 2015 with a petition.
“There were four or five of us who circulated it,” said Hudgings. “We had a 97 percent sign rate. No one wants to be sprayed.”
Leveraging an attention grabbing sign, a straight-forward message – dump that standing water; you’re breeding mosquitoes – and the persistence of its founding partners, the influence of the group grew.
“We’re both a little obsessive about the issue. We’ve learned that,” said Hudgings.
“Not extreme,” Smith clarified, “just enough.”
When your foe can breed in a thimble-full of water, vigilance pays off. Today the group has a fundraising mechanism, more than 500 names on its email list and its sights on bigger targets than backyards.
This year the group has focused on West Chester’s drainage system. Broken pipes and clogged drains that lead to hidden pools of water which can easily breed thousands of the pests. They’ve undertaken several projects to combat the problem including mapping the underground drainage system and alerting officials to clogged drains, but perhaps their most successful tactic to date has been to convince the Borough to undertake larviciding. Larviciding is a pesticide treatment that targets the larval life stage of an insect and can be applied directly to the standing water. The logic being if you can stop the larva from reaching adulthood you won’t have to spray to control them later in the season.
In the past larviciding activities, when undertaken, were done by the Chester County Health Department. According to a Right to Know request submitted by the Don’t Spray Me! team, last year 175,000 larvacidings were done in the state of Pennsylvania with just three of those in West Chester. A number described by Smith as “woefully inadequate.”
Reaping the Benefits of Prevention
Research from the National Institutes of Health suggests that consistent larviciding can be a cost effective way to control mosquito populations, especially in small to medium size towns. However, it can be labor intensive, and because it is a pesticide the individual administering it has to be licensed to apply it on public lands. At the nudging of the group, the West Chester Public Works Department complied with regulations and had someone on staff licensed to treat standing water.
Early indications are the program has been a great asset to the Borough, but we won’t know for sure until we have annual data to compare against, warned Smith. The program is currently being reviewed by the Borough for renewal next year however, even if consistent larviciding becomes the norm there will remain external factors at play.
“There is no doubt that larviciding has merit and does work,” said Evan Pilcicki, Environmental Health Specialist with the Chester County Health Department via email. “However, the pragmatist in me recognizes that even larviciding until you are blue in the face will ultimately not deter mosquitoes from finding even the smallest of suitable habitats, as they are perhaps one of the most opportunistic creatures in the animal kingdom.”
There are inevitably other factors contributing to the lower numbers as well – the cold winter, a cool spring, changes to the migratory patterns of the birds known to be the carriers of the virus – despite 20 years of research scientists are still left with many questions around why the virus behaves the way it does.
We’ll probably never be able to control all the factors influencing mosquito levels, however, we can keep being diligent in our prevention efforts. Don’t Spray Me! will be back with its neighborhood block captains and its impassioned leaders there to remind us to, dump that standing water.
In the meantime, enjoy the reprieve from the mosquito swarms, because, despite the vigilance, there is just no knowing how long it will last.
“If I’m being honest with you, the outlook for the rest of the summer may as well be like betting on the best pitcher in baseball facing off against the best hitter in baseball; it could really go either way!” said Pilcicki.
And as if on cue, the Pennsylvania’s West Nile Virus control program has logged two more WNV positives in the Borough.
“Truly, I can only continue to put my head down, treat what I can, and like the rest of the citizens of Chester County, hope for a quiet culmination of the season going into October.”
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