2 Cases of Powassan Virus Confirmed in New Jersey, but Link to 1 Death Unclear

Two cases of the rare tick-borne Powassan virus (POW) have been confirmed in New Jersey, officials with the Sussex County Division of Health announced over the weekend.

Considered an emerging disease with a growing number of human cases, the virus is transmitted via a bite from the Ixodes scapularis, or deer tick, and can cause encephalitis, meningitis, fever, headache, vomiting, weakness, confusion, loss of coordination, speech difficulties, seizures, or no symptoms at all, according to the US Centers for Disease Control and Prevention (CDC). There is no vaccine or treatment available, and individuals with other pre-existing medical conditions are at greater risk for developing complications.

“An infected tick must be attached to an individual for several hours before it can transmit the virus. A tick found crawling on a person that has not attached, has not had the time to cause infection,” the Sussex Division of Health statement reported.

Ilia Rochlin, PhD, with the Center for Vector Biology at Rutgers University, explained how rare POW is, especially in New Jersey.

“Powassan virus is a very rare infection compared to many other tick- or mosquito-borne pathogens. The CDC reported 7 cases of Powassan virus in NJ, 114 total in the US between 2008-2017,” he told Contagion®. “For comparison, there have been 163 cases of mosquito-borne West Nile Virus (WNV) (which is related to Powassan and belongs to the same family and genus, Flavivirus) in NJ and 20,511 WNV cases in the US. New Jersey alone reported over 31,000 cases of Lyme disease transmitted by ticks during the same time period.”

The New Jersey cases are concerning, especially after 1 death was reported in 1 of the infected individuals, although it’s not clear whether POW was directly responsible.

"The division has no confirmation that Powassan virus was the cause of death for any Sussex County resident," James R. McDonald III, MS, division director and health officer for the county's Department of Health and Human Services, told CNN.

Still, news of POW in New Jersey spread rapidly.

“Powassan virus elicits such intense interest for several reasons. It is the only tick-borne Flavivirus in North America and is considered emerging disease with growing number of human cases,” he said. “Powassan is closely related to tick-borne encephalitis (TBE) virus, which is a very important public health threat in Europe and Asia with thousands of cases reported annually. Like TBE virus, Powassan can cause serious illness such encephalitis or meningitis, with 10% case fatality and neurological damage in half of survivors...The rise of Powassan and other tick-borne infections is associated with the burgeoning vector tick populations.”

Health officials urge individuals to know where there are ticks in their area, always walk in the center of trails, keep yards clean, apply insecticides, cover up when outside, inspect their bodies after being outside, and take a shower after spending time outdoors.