State health officials are warning residents to protect themselves from mosquito bites as more cases of West Nile virus crop up across the state.

On Wednesday, a Newton woman was recovering from West Nile the fourth confirmed human infection in Massachusetts. While mosquitoes detected with eastern equine encephalitis (EEE) have fallen off slightly, detection of West Nile is on the rise, according to an official at the Department of Public Health.

So far this season, four people have been infected with West Nile, and one with EEE, according to state health officials.

West Nile cases are also on the rise nationally, according to a Department of Public Health official. In Massachusetts, state health officials have found infected mosquitoes in 93 communities.

"Over the last three weeks or so, West Nile has been dramatically increasing," said Dr. Catherine Brown, state public health veterinarian. "It is very high."

Brown said the "bad news" is the number of communities with West Nile-infected mosquitoes could be much higher some communities are not tested. Only communities that are a part of one of the nine mosquito control projects test.

"What this tells us is there is a lot of West Nile everywhere," Brown said. "At this point, people should consider that West Nile virus is present throughout the state."

West Nile virus was first found in Massachusetts in 2000. There were bad outbreaks in 2002-2003, with 22 and 18 human infection cases respectively. Since then, the number of cases hasnt hit those levels, according to Brown.

The summers high temperatures and dry conditions created ideal conditions for mosquito-borne infections.

"The heat, not only does it speed up mosquito reproduction, it also speeds up the virus multiplication. The mosquitoes infect the birds; the birds infect more mosquitoes," Brown said. "That whole cycle between the birds and the mosquitoes is called virus amplification."

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Mass. health official says West Nile virus all over the state