ATLANTA – A salmonella outbreak potentially linked to produce has sickened at least 172 people in 18 states, including Maine and other New England states, health officials said Monday.

Seven cases affecting adults and a few children have been reported in southern Maine over the past several weeks, according to Dr. Dora Anne Mills, Maine’s director of public health. No one was hospitalized.

Maine’s department has been working with New Hampshire public health officials because of reports in that state of illnesses also caused by salmonella typhimurium, Mills said. The cases were reported to the U.S. Centers for Disease Control and Prevention, but Maine public health officials had not heard from the CDC about illnesses in any other states.

“It’s not linked to any Maine produce,” but it is important for people to maintain good kitchen hygiene, Mills said.

“That means disinfecting the kitchen sponge, and whatever people use to wash dishes that hangs out on the kitchen sink,” as well as fully cooking poultry and meat, thoroughly washing fruits and vegetables, and cleaning knives, Mills said.

Health officials think the bacteria may have spread through some form of produce – the list of suspects includes tomatoes. But the illnesses have not been tied to any specific product, chain, restaurants or supermarkets.

No one has died in the outbreak, which stems from a common form of salmonella bacteria. Eleven people have been hospitalized, health officials said.

“We’re very early in the investigation,” said Dave Daigle, a spokesman for the U.S. Centers for Disease Control and Prevention.

The CDC detected the outbreak two weeks ago through a national computer lab system that looks for patterns and matches in reports of food-borne illness. The U.S. Food and Drug Administration has joined the investigation and will try to help trace the outbreak to its origin.

Most of the cases are in adults, and more than 60 percent are women, said Dr. Chris Braden, a CDC epidemiologist investigating the outbreak.

Fifty-one cases reported in Massachusetts in September are the same strain as that in the national outbreak, said Donna Rheaume, a spokeswoman for the Department of Public Health. None of the cases had serious outcomes, and no new cases have been reported since the end of September. Most were in eastern Massachusetts. The state typically has about 1,300 cases of salmonella in a year, she said.

The other states involved are Arkansas, Connecticut, Georgia, Indiana, Kentucky, Maine, Michigan, Minnesota, North Carolina, New Hampshire, Ohio, Pennsylvania, Rhode Island, Tennessee, Virginia, Vermont and Wisconsin.

Salmonella generally cause a nonfatal, diarrhea-causing illness. Other symptoms can include nausea, vomiting, abdominal cramps, fever and headache.

There are about 2,500 types of salmonella. The type in this outbreak – Salmonella typhimurium – is one of the most common, Braden said.

People can catch the infection from many different sources, including water, soil, insects, factory surfaces, kitchen surfaces, animal feces, and raw meats, poultry and seafoods.

Outbreaks of food-borne illness have repeatedly made headlines this year. Certain brands of packaged spinach, lettuce, carrot juice, beef and unpasteurized milk recently were recalled after they were found to be tainted with illness-causing bacteria.

The most serious outbreak, reported in September, involved spinach tainted with E. coli bacteria that killed three people and sickened more than 200. Three cases were reported in Maine.

Health officials estimate that more than 1.4 million cases of salmonellosis occur in the U.S. each year. About 1.3 million of those cases come from food, Braden said.

– Staff Writer Laurie St. Pierre contributed to this report.