With tick-borne viruses such as Powassan virus increasing in Canada, clinicians should consider these infections in patients with encephalitis, as a case study shows in CMAJ ( Canadian Medical Association Journal ) https://www.cmaj.ca/lookup/doi/10.
1503/cmaj.240227 . Although rare, Powassan virus is serious, with a death rate of 10%–15% in people with encephalitis, and it can cause lingering health effects after infection.
The virus can transmit within 15 minutes of tick attachment, and symptoms can develop 1–5 weeks later. In this case study, a 9-year-old child with up-to-date vaccinations was admitted to hospital after a visit to an emergency department for fever, neck stiffness, and headache that developed 1 week after a camping trip in northern Ontario. Physicians conducted extensive testing for a range of illnesses including Epstein–Barr virus, Lyme disease, bacterial meningitis, and more.
They also sent serology samples for testing at the Public Health Ontario laboratory, but the results were not available for several weeks. The eventual diagnosis, confirmed after the child was discharged, was Powassan virus. Related Stories FDA commercial pasteurization process kills H5N1 bird flu virus in milk Recombinant shingles vaccine linked to lower dementia risk, especially in women APOE ε4 carrier status increases the long-term cognitive decline risk associated with herpes zoster Cases of encephalitis from Powassan virus and other tick-borne illnesses have been increasin.