BOSTON (AP) – State public health officials confirmed the first two human cases of West Nile virus in the state since 2003 as Gov. Mitt Romney warned residents to take precautions against mosquito bites.

Romney issued a public health alert for both West Nile virus and Eastern Equine Encephalitis, which humans can contract from bites from two different kinds of mosquitos.

Lab test confirmed that a 33-year-old Boston woman and a 56-year-old Newton woman have contracted West Nile virus.

The Boston woman, who became ill Sept. 1, has recovered after five days in the hospital. The Newton woman became ill on Sept. 4 and remains hospitalized.

Also this year, the state has recorded four cases of EEE virus, two of which resulted in deaths. New Hampshire has had five EEE cases and one death.

Public health officials said it’s rare to have this many infections so late in the summer.

“It hasn’t gone away,” Romney said. “In fact, this incidence so late in the year is somewhat unprecedented. We don’t quite know where this is going to go.”

Because West Nile bites are caused by mosquitos found in puddles and dirty water, Romney warned people to drain standing water, empty unused flower pots and wading pools and check rain gutters and drains.

“Dirty water and puddles exist just as much in cities as that water exists out in the rural communities,” he added.

Mosquitos that transmit EEE are found in swamplands or wooded areas.

Romney also urged residents to avoid outdoor activities between dusk and dawn, or to wear insect repellent, long sleeves, long pants and socks while outdoors.

“This is the more serious of the two illnesses because it has a much higher mortality rate,” Romney said of EEE. “The best way to avoid this illness is to simply stay away from the woods and tall grasses and wet grass.”

Some communities have been spraying insecticide from the ground level.

Alfred DeMaria, chief medical officer for the Department of Public Health, said aerial spraying isn’t necessary because mosquitos tend stay lower to the ground in cooler weather.

“We’re watching this very closely, and things could change. We want to keep all of our options open,” DeMaria said.

Since 2001, Massachusetts has had 49 confirmed cases of West Nile Virus and nine cases of EEE, including four fatalities.

“But we’ve only had about 80 cases of Eastern Encephalitis since 1938, so that’s what’s unusual,” DeMaria said.

This isn’t the first time the state has issued a public health alert for mosquito-borne illnesses. However, Romney determined that declaring a state of public health emergency wasn’t necessary.

“A state of emergency would be when you want to do extraordinary things,” DeMaria said. “It doesn’t really merit that kind of extraordinary action.”