West Nile Virus prevention happening in Montgomery County

As Montgomery County ramps up local prevention efforts against West Nile Virus, public health officials outlined ways they’re reducing exposure.

The mosquito-borne disease is considered the “most common” in the state, according to Christina Miller, administrator of the Montgomery County Department of Health and Human Service’s Office of Public Health.

West Nile Virus has been detected in nearly every county in Pennsylvania, according to the state’s West Nile Virus Activity Map 2025. Symptoms associated with West Nile Virus can present as flu-like, Miller said last week, noting body aches, diarrhea, fever, headache, nausea, rash and vomiting as common ones.

In her presentation, Miller noted “there’s no treatment for West Nile Virus,” but she added that only about one in 150 cases “result in serious illness, such as encephalitis or meningitis, or death.”

In order to perform “integrated mosquito management” practices, Miller said the county’s public health office “monitor[s] for diseases” by “collecting and testing mosquitoes for diseases that can harm human health.” She added that more than 500 samples have been taken so far this year.

“Of those, around 400 samples met the criteria for lab testing.” Around 120 of those samples tested positive, according to Pennsylvania Department of Environmental Protection findings.

Miller stressed cases remain “relatively low,” and “that alone isn’t enough to prompt us to move into action.”

While the state agency is “responsible for control of West Nile Virus,” Miller acknowledged that “implementation happens at the county level.”

To comply with Pennsylvania code, the county health department has implemented “source reduction” with respect to “controlling the mosquito population at all stages.”

The county agency has surveyed select areas of Abington, Montgomery and Whitpain townships so far this year, spraying .75 ounces of Duet® Duel-Action Adulticide fluid per acre from a truck mounted with an ultra low volume sprayer in order to identify areas where mosquitoes are breeding and eliminate and/or treat with larvicide.

In her presentation, Miller stressed the “dosage is very limited,” likening it to “one tablespoon for an area the size of a football field.” Advanced notice was given to neighbors as the actions took place in the evening hours on certain days last month.

“We want people to know this is happening,” Miller said.

County public health officials in a recent statement offered the following tips to eliminate mosquito breeding areas:

• Check and repair windows and screens to prevent mosquitoes from entering the home.
• Regularly survey property and eliminate standing water and dispose of containers that can collect standing water such as old tires, cans, bottles, buckets, and toys. Anything that can hold water for five days can breed thousands of mosquitoes. Eliminating standing water has proven effective in controlling mosquito populations and the spread of diseases they carry.
• After it rains, empty plant containers, bird baths, flowerpots, kiddie pools, and pool covers in order to keep water from collecting in them. Make sure roof gutters drain properly, and rooftops are free of standing water.
• Clean and chlorinate swimming pools, outdoor saunas, and hot tubs. Keep them empty and covered if not in use; drain water that collects in pool covers.
• Drill several holes in the bottom of recycling buckets so water can drain from them. Cover trash and recycling bins so that rain cannot accumulate in them.

Typically, registered beekeepers, people on the Pennsylvania Department of Agriculture’s Pesticide Hypersensitivity Registry and area residents signed up for ReadyMontCo alerts will be alerted to pesticide-related activities. Those interested in receiving notifications can sign up at readymontco.org.

“Thank you for bringing evidence and information to the presentation,” said Montgomery County Commissioners’ Vice Chairwoman Jamila Winder.

Visit montgomerycountypa.gov/513/Public-Health for more information.