Two viruses have shown up in New Hampshire for the first time — in the same person.
The first appearances of Jamestown Canyon virus and Powassan virus were found in an adult male in Hillsborough County, the Department of Health and Human Services announced yesterday.
“These are two diseases that are still very rare,” said Chris Adamski of the Bureau of Infectious Disease Control. “We still don’t know a lot about them.”
Jamestown Canyon is a mosquito-borne illness, while Powassan is transmitted by ticks.
“This is very unusual that the same person would have both of these,” Adamski said. “But it’s not unheard of. We don’t know if one came before the other or how this occurred.”
State entomologist Piera Siegert said a deer is likely a common link between the two viruses.
“Any time that an animal has intimate contact with your blood supply, which ticks and mosquitoes do, there is a possibility of transmitting disease,” Siegert said. “This is an extremely small possibility this would happen, but the potential is always there.”
DHHS would not release the man’s age or hometown.
Powassan virus is similar to West Nile virus, but it is transmitted ticks rather than mosquitoes. Fewer than 60 cases of the disease have been detected in the United States and Canada since its discovery in 1958. The virus can infect the central nervous system and cause brain inflammation. Some people who contract the virus experience mild symptoms, some none at all.
Just a day earlier, DHHS announced two mosquito pools in Pelham tested positive for West Nile virus, the first such findings this year.
Jamestown Canyon virus is often milder, but it, too, can affect the central nervous system. The virus is often transmitted between mosquitoes and deer, but is rarely found in humans.