Re: “Researchers concerned by virus that killed well-known Maine artist” (Dec. 25):

The U.S. Centers for Disease Control and Prevention publication Mortality and Morbidity Weekly Report (Sept. 7, 2001, Vol. 50, No. 35; pages 761-764) documents the first identification of the Powassan virus in Maine, in September 2000.

The diligence of what was then the Maine Bureau of Health, under Dr. Dora Anne Mills, led Maine state epidemiologists to send antibody samples to labs nationwide to identify what was at the time an unidentified virus in Maine.

They also then looked at antibody samples from cases in Maine of viral encephalitis with previously unidentified viruses. The Powassan virus was then identified in prior and subsequent cases in Maine and Vermont.

The activity of the bureau (now known as the Maine Center for Disease Control and Prevention) was summarized in a journal article written by those epidemiologists and referenced in the Mortality and Morbidity Weekly Report article.

Squirrels – in particular, red squirrels – are identified in the article as carriers of the tick species Ixodes cookei, which transmits Powassan. Red squirrels are more prevalent, thus a greater concern, than woodchucks, which also carry Ixodes cookei.

Are unidentified viral antibodies from cases of viral encephalitis still routinely sent to the Maine CDC and checked for the presence of Powassan, or has that been cut from the state budget, too?

Susan Cook

Bath