The Texas Department of Health (TDH) has ended an eight-week long investigation into a salmonellosis outbreak in people who had consumed food or beverages at the Wyndham Anatole Hotel in Dallas in March and April.

TDH lead epidemiologist Kathleen Shupe-Ricksecker said the outbreak and the investigation are over.

She said investigators believe a hotel foodservice worker who did not have symptoms of the illness, but who later tested positive for the bacterium that causes the illness, may have introduced Salmonella into the hotel.

Shupe-Ricksecker said the food most commonly consumed by those who tested positive for salmonellosis was salsa, which was made in the hotel.

Some 50 people were confirmed to have salmonellosis, and 650 people from all 50 states reported having had symptoms consistent with the illness.

Among the laboratory-confirmed cases, the first illness onset date was 16 March; the last was 25 April.  Nine other foodservice employees also became ill and tested positive for  Salmonella.

“We do not know how or where that first employee became infected, and we do not know for a certainty that the employee was the original source of infection,” Shupe-Ricksecker said.  “But because results of environmental tests in the hotel and tests of water, ice and selected food from the hotel were negative, our suspicion is that the employee became infected elsewhere.”

Shupe-Ricksecker said hotel staff cooperated fully with investigators and voluntarily took  precautionary measures during the investigation including serving bottled water, purchasing  commercially prepared ice, temporarily relocating its main banquet food preparation to a secondary kitchen and requiring food handlers to show negative tests for Salmonella before being allowed to work.

The City of Dallas Department of Environmental Health Services, the Dallas County Health and Human Services Department and the US Centers for Disease Control and Prevention were also involved in the investigation.

Salmonellosis is usually contracted by consuming contaminated food or drink. The illness also can be spread person-to-person by a fecal-oral transmission route.