BOSTON (AP) — Massachusetts health officials say a Berkshire County woman in her 70s is the state’s third West Nile virus patient this year.

Authorities said Friday the woman is expected to be released from hospital soon. Two Cambridge men, one in his 60s and the other in his 70s, also have the mosquito-borne virus.

The Centers for Disease Control and Prevention says only about one in five infected people get sick. But patients also can suffer severe symptoms or die.

The latest case forced health officials to raise the virus risk levels to “high” for Pittsfield, meaning human cases are very likely. The risk was raised to “moderate” for Dalton, Hancock, Lanesborough, Lenox, Richmond and Washington — meaning human cases are moderately likely.

Authorities recommended draining pools of standing water and using bug repellent as some precautions against infection.

Copyright 2012 The Associated Press.