West Nile Virus is still with us, but risks can be mitigated

At first blush, it felt like a story out of a distant past.

As Bill O’Boyle reports in today’s edition, the Pennsylvania Department of Environmental Protection Vector Management has announced that two mosquito samples tested positive for West Nile Virus (WNV) in Hanover Township and Butler Township.

Seriously, is this 1999 or something?

That was when the first cases were reported in the U.S. As those of a certain age will recall, the following summers brought what seemed like a never-ending parade of press releases about positive samples as the disease spread.

After a time, as with so many things, West Nile faded into the background for most of us, something that grabbed the headlines every now and then, but mostly taking a back seat to other concerns — including other health concerns. It wasn’t exactly a global pandemic, you know?

But the truth is that the disease is still very much with us, and still poses some very real risks.

According to the Centers for Disease Control and Prevention, WNV is the leading cause of mosquito-borne disease in the continental United States. It is most commonly spread to people by the bite of an infected mosquito.

There were 56,569 human cases in the U.S. from 1999-2022, of which 25,769 resulted in hospitalizations and 2,773 were fatal, CDC records show. The peak year was 2003, with over 9,800 cases. Numbers did decline substantially in the following years — cases haven’t exceeded 5,000 nationwide since 2012, and dipped below 1,000 in 2019 and 2020 — but WNV has never been completely eradicated.

The number of cases in Pennsylvania has been relatively low — just 768 from 1999-2022, CDC reports. No human cases have been reported in the state so far this year.

Fortunately, the CDC notes, most people infected with WNV do not feel sick. About 1 in 5 people who are infected develop a fever and other symptoms. About 1 out of 150 infected people develop a serious, sometimes fatal, illness, however.

There are no vaccines to prevent or medications to treat WNV in people, the CDC says. But you can reduce your risk of WNV by using insect repellent and wearing long-sleeved shirts and long pants to prevent mosquito bites.

Cases of WNV occur during mosquito season, which starts in the summer and continues through fall, the CDC notes. Thus, keeping the pests at bay during that time is key to staving off the spread of the disease.

O’Boyle’s story pointed out steps we all can take to mitigate the risk.

“We recommend residents take time to inspect their yards and take a few minutes to clean up and dump out any sources of stagnant water,” said Keith George, Special Projects Coordinator, Mosquito-borne Disease Control Program Coordinator, Luzerne Conservation District. “Mosquito surveillance indicates that many common mosquito species in residential areas come from artificial containers left behind by humans.”

George said artificial containers, such as tires, buckets, child toys, tarps and even swimming pools are preferred by mosquitoes because natural predators that prey on mosquito larvae are not present.

George said that during periods of drought, these containers continue to hold water and produce mosquitoes. Cleaning them up reduces the risk. Stormwater management systems can sometimes contribute to mosquito issues and are also routinely monitored by his office’s staff.

He also said residents should use repellents when spending time outside, a variety of which can be found at most home and garden centers. Residents also can purchase insecticides from garden and hardware stores to spray in their yard but they need to be sure to follow the label instructions.”

Residents with questions can contact the Luzerne Conservation District Mosquito-borne Disease Control Program by calling 570-674-7991, Ext. 6, or email mdc@luzernecd.org.

More information about WNV in general can be found at www.cdc.gov/westnile/index.html.

— Times Leader