Fourteen Boy Scouts and one adult contracted an E. coli infection while attending a popular camp in Virginia’s Blue Ridge Mountains.

The Virginia Department of Health began receiving reports on Sunday when the boys from about 70 troops returned home after a week spent at the Goshen Scout Reservation in Rockbridge County (between July 20 and 26). About 950 scouts attended the camp. Nine of 50 to 60 scouts who reported being ill have been hospitalized. Their condition is not known. Health officials fear that the number of illnesses could grow.

The source of contamination has not been determined yet. E. coli is most commonly caused by undercooked contaminated ground beef. Some 30 employees at the Virginia Department of Health were investigating the outbreak, interviewing Scout troops and taking stool samples from those showing symptoms.

“Public health officials are working closely with reservation staff to explore possible sources of the infection through interviews with staff, troop leaders, parents of ill children and health-care providers,” Department epidemiologist Seth Levine said. However, he said it was too early to link the outbreak to ground beef or any other sources.

Alan Lambert, Scout executive of the Boy Scouts of America's National Capital Area Council said Scout leaders are taking measures to reduce the risk of contamination.

"Our goal is to reach out personally to every family affected by this incident and to assist as necessary while the boys recover," Lambert said.

E. coli is a potentially deadly bacterium that can cause diarrhea, stomach cramps, vomiting and in most severe cases kidney failure. Most of the infected persons get well in 15 days. People predisposed to the infection include children, seniors, and persons whose immune system is weakened. Antibiotics typically are not helpful, and infections are often treated by drinking fluids and taking pain relievers.

The CDC estimates that there may be about 70,000 infections with E. coli annually in the United States, with many of these cases not seeking medical care.

Last month, some 41 people from Ohio and Michigan were infected with E. coli bacteria. Following this outbreak, US’s largest grocery chain, the Kroger Food Store, voluntarily recalled all ground beef products that were sold between May 21 and June 8 at its stores. Soon after, Nebraska Beef Ltd. announced a massive meat recall to 5.3 million pounds, which represents all the meat that the company produced between May 16 and June 26.