Columbus health officials are investigating what they call an “unprecedented large number of Shigella illness” in the area.

Since the start of the outbreak, 771 cases have been diagnosed.

That’s the largest number of cases in any year in the last decade.

Shigella is a bacterium that causes an infection of the intestine called Shigellosis. It causes diarrhea which may be bloody, and can cause severe dehydration and hospitalization. Found in human feces, this bacterium can get on hands when using the toilet or changing diapers.

A bacterial illness is plaguing day-care centers in central Ohio, and health officials warn it could spread if parents aren’t vigilant.

The Columbus Dispatch reports Wednesday that the number of reported cases of shigella more than doubled in September in Franklin County, which includes Columbus. There have been 435 cases, compared with reported numbers in the teens the past two years.

The disease causes diarrhea and is easily spread if care isn’t taken when changing diapers, preparing food and cleaning up after bathroom breaks.

Dr. Mysheika Roberts, Columbus Public Health’s medical director, says there have been confirmed cases of shigella at 30 day-care centers in the city this year.

Misti Crane of the Columbus Dispatch – Columbus and Franklin County health officials are warning day-care providers to take precautions against spreading a bacterial infection that causes diarrhea and can be especially harmful to people with weak immune systems.

Shigella cases are on the increase in the county, especially in the city, and most have been linked to day-care providers where more than one child has been infected, said Columbus Public Health medical director Mysheika Roberts.

There have been 144 known cases this year, many of those in the past few weeks, and most in children younger than 4.

Since May, the Douglas County Health Department has investigated 50 confirmed cases of Shigella sonnei (shigellosis) infection, including four that involved hospitalizations. In eight of the nine previous years, Douglas County reported 31 or fewer cases.

Symptoms of shigellosis can range from loose, watery stools with no other symptoms to bloody diarrhea with fever and cramps. People experiencing diarrhea should remain home from school or work until at least 24 hours after their symptoms stop. Anyone with diarrhea should not prepare food or drink for others.

“Hand washing is absolutely critical to controlling any disease that involves diarrhea,” Health Director Dr. Adi Pour said. “It is especially important to wash your hands with soap for at least 20 seconds after changing diapers or using the bathroom, since it takes only a small exposure to pass along the disease.”

Forty-one percent of these recent shigellosis cases involved children less than 5 years old and 29 percent were between 5 and 9 years old. Most of the cases, 62 percent, have been associated with child care settings.

It is also important for anyone who has been sick to stay out of swimming pools and water parks for a week after they have recovered. Most of the recent Douglas County cases are linked to day care facilities, but swallowing pool water is another way shigellosis may be transmitted.

The Okaloosa County Health Department (OCHD) is reporting an increase in Shigella cases county-wide, with 49 laboratory confirmed and probable cases since the beginning of this year. Since 2000, Okaloosa County has averaged 3 cases of Shigella per year (range 0 – 7). The health department has been working diligently to implement prevention and control measures with child care centers, community health care providers, congregate living facilities, and the Department of Children and Families.

Shigella is a group of bacterial that causes shigellosis. Shigellosis is usually a mild, self-resolving diarrheal illness (meaning the body will fight off the infection without treatment). Most people recover completely within 4 to 7 days. After a person is infected, symptoms may develop within 1 to 3 days. The diarrhea is watery and sometimes bloody. Other symptoms include nausea, vomiting, abdominal pain, and fever. Some people never develop any symptoms after being infected.

The number of Onondaga County residents sickened by a gastrointestinal illness that surfaced in late June has climbed to 55 and public health officials still have not identified the source of the outbreak.

Children under 10 account for about half of the 55 confirmed and probable cases of shigellosis, a bacterial infection, said Dr. Cynthia Morrow, Onondaga County’s health commissioner.

Many people who are infected develop fever, painful blood or mucous diarrhea, fever and stomach cramps a day or two after being exposed to the bacteria, called shigella. The illness usually clears up in five to seven days. Severe cases need to be treated with antibiotics.

A few of the people infected have been hospitalized, Morrow said.

The bacteria is present in the stools of infected people. It can be spread when infected people fail to wash their hands before handling food eaten by others or coming into contact with others.