West Nile Virus Cases Rising in Lancaster County

Recently, Lancaster County reported another case of West Nile virus, bringing the total number of human cases to five for the year. It’s a bit unsettling, really. Though the specific infection dates aren’t available, the Pennsylvania Department of Environmental Protection included this case in a weekly report released on Friday. The other four cases likely occurred in July and August, as suggested by the state’s health officials.

The five cases in Lancaster County make up a significant portion of the 25 human cases recorded across Pennsylvania this year. It’s interesting to note that just a year prior, there were no reported cases in the county, and there were two fatalities in 2024. It’s somewhat alarming to think how quickly things can change.

West Nile virus primarily affects birds, yet it emerged in Pennsylvania back in 2000. The virus is usually transmitted through infected mosquitos; it’s not something that spreads easily between people. For instance, you can’t catch it from someone via coughing or sneezing, according to the CDC. Cases typically surge in late summer, particularly from late August into early September.

Breakdown of Human Cases by County

• Adams: 0
• Berks: 2
• Chester: 1
• Cumberland: 2
• Dauphin: 0
• Franklin: 0
• Lancaster: 5
• Lebanon: 0
• Perry: 0
• York: 2
• Statewide: 25

How to Prevent Infection

Currently, there are no vaccines or medications against West Nile virus, so the CDC recommends avoiding mosquito bites. Consider wearing loose-fitting, long-sleeved clothing and using EPA-registered insect repellent containing DEET or similar ingredients. It’s also wise to manage your surroundings by eliminating standing water, which can become breeding grounds for these pests.

Understanding the Health Risks

I think many people might not realize that most who contract West Nile virus show no symptoms at all. About 20% may experience flu-like symptoms, while a smaller fraction, less than 1%, develop serious complications affecting the central nervous system. In fact, the severe form can lead to brain inflammation and even death, with a disturbing 10% mortality rate for those seriously affected.

Age appears to be a critical factor; older adults—especially those over 65—face a significantly higher risk for serious disease. Conditions like cancer or diabetes can further elevate that risk, making it essential to be cautious.

Symptoms to Watch For

While about 80% of infected individuals remain symptom-free, the rest might display mild to severe symptoms. If symptoms do appear, they generally manifest two to six days post-infection, although it can take up to 14 days in some cases.

Common mild symptoms include:

• Fever
• Headache
• Body aches
• Joint pain
• Vomiting
• Diarrhea
• Rash
• Fatigue or prolonged weakness

For those who suffer severe illness, the symptoms can escalate quickly, leading to dire consequences. Symptoms of severe illness may include:

• High fever
• Severe headache
• Neck stiffness
• Disorientation or confusion
• Coma
• Muscle weakness
• Numbness or paralysis