A Pennsylvania woman in her 80s has died after contracting West Nile virus, health officials said this week.
The woman lived in Pittsburgh and is the first human case reported in Allegheny County this year, according to the Allegheny County Health Department (ACHD).
Officials said the woman experienced fever and weakness and was eventually hospitalized before she passed away in late September. No other information about the patient will be released, the department said.
Earlier this summer, the ACHD said it had detected West Nile virus in Pittsburgh-area mosquitoes.
ACHD officials said in this week’s announcement that they are setting up additional traps, including in the neighborhood where the patient lived, and are targeting other areas with a mosquito pesticide.
West Nile virus is the leading cause of mosquito-borne disease in the continental United States, according to the Centers for Disease Control and Prevention. It was first introduced in the Western Hemisphere during the summer of 1999, after people were diagnosed in New York City.
Mosquitoes typically become infected with the virus after feeding on infected birds, and then spread it to humans and other animals when biting them, the federal health agency said. West Nile virus is not spread through coughing, sneezing, interpersonal contact, or eating infected animals, such as birds.
Most people with West Nile virus do not experience symptoms, but about one in five will experience fever along with headaches, body aches, joint pain, diarrhea, vomiting or a rash. Most symptoms soon disappear, though weakness and fatigue may last for weeks or months.
About one in 150 people infected with West Nile virus will develop severe disease leading to encephalitis, which is inflammation of the brain, or meningitis, which is inflammation of the membranes that surround the brain and spinal cord. Both conditions can be fatal.
There are currently no vaccines for West Nile virus, nor disease-specific treatments. The CDC recommends rest, fluids, and over-the-counter medications to treat the infection. Those with severe illness may need to be hospitalized and receive additional support treatments, such as intravenous fluids.
This year, Pennsylvania has reported 10 cases of West Nile virus to the CDC, according to the Allegheny County Health Department. There were two cases of West Nile virus in Allegheny County last year and three cases in 2021.
To best protect yourself from infection, or from mosquito bites in general, the CDC suggests using insect repellent, wearing long-sleeved shirts and pants, treating clothing and gear with insecticide, and taking broader steps to control mosquitoes. This last step includes putting screens on windows and doors, using air conditioning, and regularly emptying containers filled with still or stagnant water.
The Allegheny County Health Department said residents who see mosquito breeding sites can report them online, or by calling (412) 350-4046.