Shigella cases are way up in Stanislaus County and health officials can’t explain it

Stanislaus County health officials have no specific explanation for a spike in intestinal illness this year that now threatens to ruin the holidays for some folks.

The county’s public health staff has confirmed 123 cases of Shigella infection this year. That is more than six times the 19 confirmed cases of Shigellosis here in 2015.

The county issued an initial warning about Shigella in August when it had confirmed 47 cases in eight months.

Anuj Bhatia, county public health division manager, said officials are not seeing a pattern for the cases or outbreaks tied to specific locations. “It is really all over the place,” he said.

Those stricken by the illness have ranged in age from 1 to 81 years old, with 38 of the patients younger than 21 and 65 of them being ages 21 to 65. Some of the patients have been hospitalized, though the county did not have a count.

More than 75 percent of the county caseload has been in Modesto, most likely because it’s the city with the largest population, Bhatia said. The Shigella cases have been reported to the Stanislaus County Health Services Agency by hospitals, physicians and other health care providers.

“I believe there is an increase across the state and in some other counties,” Bhatia said.

According to the Centers for Disease Control and Prevention, the illness caused by bacteria often results in mild to severe diarrhea, fever and painful stomach cramps a couple of days after exposure to the bacteria. The diarrhea may have traces of blood.

About 500,000 cases occur in the United States every year, with children and seniors at the highest risk of a serious illness requiring hospitalization.

The disease lasts five to seven days; some infected people have no symptoms but can give the bacteria to other folks. Infected people spread the bacteria by touching objects or contaminating food that is then consumed by other people. Health officials are stressing hand-washing as people gather for holiday activities.

“Regular and frequent hand-washing with soap and running water is the single most important preventive measure to interrupt the spread of Shigellosis,” said Dr. John Walker, county public health officer.

Walker advised residents to thoroughly wash their hands after using the restroom or changing babies’ diapers. The same routine is advised before preparing food or sitting down to a meal.

The hand-washing instructions are especially important for people diagnosed with a Shigella infection, Walker said.

The Shigella group of bacteria occurs in every area of the United States, and infections may be tied to child care centers and nursing homes or contaminated food in restaurants. Outbreaks have occurred when drinking water is tainted by sewage overflows or polluted stormwater contaminates wells, the CDC says.

Outdoor enthusiasts may become infected by drinking contaminated lake or river water.

In California, health officials have paid more attention to Shigella illness after outbreaks over the past 14 months.

In fall 2015, a Shigella outbreak affecting almost 200 people in the Bay Area was connected with a seafood restaurant in San Jose.

In August, the California Department of Public Health reported it was investigating a cluster of Shigella infections in Southern California among men who have sexual contact with other men. According to a news release, five of the 14 patients infected with an uncommon strain of the bacteria were hospitalized. The news release said strains of Shigella resistant to antibiotics appeared to be circulating among gay men in California and nationwide.

According to state data, cases of Shigellosis more than doubled over five years in California, growing from 949 in 2011 to 2,231 cases in 2015. Stanislaus County averaged 17 annual cases during that period before the dramatic spike this year.

Bhatia said county health officials are not investigating any specific outbreaks but continue to monitor the cases.

This story was originally published December 20, 2016 at 6:24 PM with the headline "Shigella cases are way up in Stanislaus County and health officials can’t explain it."