Monitoring: Vector-Borne Diseases

This page is the collection of any information about vector-borne diseases in Pennsylvania.

Ticks

Since 2017 Asian lonhorned tick (Haemaphysalis longicornis) is an invasive spiecies spreading throughout Pennsylvania and other states. Pa. Environmental Protection article, PSU Ext. article, PSU Ext. Ticks & Disease. This tick can infect humans with a virus that causes severe fever with thrombocytopenia syndrome. Which may lead to a fatal hemorrhagic fever. This virus has not yet been found in any of the ticks in the U.S.

West Nile Virus and Jamestown Canyon Virus

West Nile Virus and Jamestown Canyon Virus can both infect humans and both have been detected in multiple counties. page on this issue. Pa. Dept. of Environmental Protection

2025-07-18 Philadelphia health department warns of mosquito-borne West Nile virus. PSU Extension, CDC

Cochliomyia hominivorax, the New World screwworm fly, or simply screwworm or screw-worm

The US Department of Agriculture announced that the import of foreign livestock from Mexico will recommence on July 7th, 2025. The import of all livestock had previously been halted in May due to an outbreak of New World Screwworm (NWS) in Mexico, a flesh-eating parasite which is infamous for devastating entire herds of cattle, deer, and bison.