PORTLAND – West Nile virus may capture headlines as an emerging disease, but Lyme disease remains a bigger threat in Maine, says the director of the state Bureau of Health.

“With such a big focus on West Nile virus, some people are not getting the message about Lyme disease,” director Dora Anne Mills said.

Since the 1980s, hundreds of Mainers have been sickened by Lyme disease but no humans in the state have been infected by West Nile virus, Mills said.

West Nile virus is a mosquito-borne disease, while Lyme is spread by deer ticks. Health officials say there are a few simple steps that Mainers can take to lower their chances of contracting either disease.

One is to reduce bug populations by clearing out brush and logs from yards and removing any standing water. Officials also recommend putting on DEET-containing insect repellent and wearing clothes that provide sufficient coverage to help ward off bug bites.

The state has been promoting such safeguards as part of a public information campaign.

“It’s becoming increasingly clear to us that West Nile virus and Lyme disease have overlapping prevention strategies,” Mills said.

Each year, about 200 people in Maine get Lyme disease, a bacterial infection that can cause arthritis, neurological problems and encephalitis, a potentially fatal brain inflammation.

Early symptoms include a red “bull’s-eye” rash that slowly expands within three to 30 days of a tick bite and may be accompanied by joint and muscle pains and fever.

West Nile virus has stricken more than 16,500 people and killed more than 650 since it first appeared in the United States in 1999. Most people with the virus don’t get sick, but symptoms such as aches, fever and vomiting are more apt to show up in people who are 50 and older or have weakened immune systems.

Although more than 100 birds in Maine have tested positive for the virus since 2001, the state is the only one east of the Mississippi that has not yet confirmed a human case of West Nile virus.

“I think that could certainly change at any time,” said Dr. Kathleen Gensheimer, state epidemiologist. She noted that Canadian provinces north of Maine have reported human cases and does not know why Maine has been spared.