Three people are now hospitalized in serious condition with complications from E. coli 0157, an infection linked to a July 3 carry-in picnic.

All three — a 4-year-old girl, a 14-year-old boy, and a 73-year-old man — have developed hemolytic uremic syndrome (HUS), which can lead to acute, short-term kidney failure.

The outbreak, which is apparently linked to a July 3 customer appreciation picnic at Neff’s Lawn Care in Germantown, has sickened 68 people and sent 14 to the hospital, said Bill Wharton, spokesman for Public Health - Dayton & Montgomery County. Only the three who have developed HUS remain hospitalized, Wharton said.

Of the 68 who developed symptoms, including stomach cramps and diarrhea, 16 have been confirmed by lab testing as having E. coli 0157.

Calls to the health department to report illnesses after the picnic have “drastically dropped down,” he said. But on July 16, the first secondary infection in the outbreak was reported when a person who ate contaminated food served at the picnic passed the disease to a household member who did not attend the picnic. An older sister “likely” spread the infection to a younger sister, Wharton said.

The secondary infection emphasizes the need for good hand washing, he said. E. coli is spread through contaminated food, but it can also be spread from person to person.

“It’s even more imperative that those 68 people who are ill understand that they need to wash their hands so they don’t give this to family members,” Wharton said.

As many as 300 people attended the annual picnic at Neff’s Lawn Care, health officials said. The hosts provided some food on-site, and people attending the picnic brought in food as well.

Health department staff are continuing to try to trace the source of the outbreak, Wharton said. Investigators are asking people who developed symptoms what they ate, how much they ate and when they ate it, he said, as well as trying to determine how food served at the picnic was prepared and stored.

Food safety is always a concern at public gatherings, but it’s especially problematic during the summer, when large outdoor gatherings are common and food could be kept at the wrong temperature for long periods of time. To keep dangerous bacteria like E. coli or salmonella from developing, it’s important to store cold foods at temperatures below 40 degrees and hot foods at temperatures warmer than 14o degrees.

Caterer Steve Bernstein, who owns and operates Bernstein’s Fine Catering in West Carrollton, said he isn’t yet seeing an uptick in business because of concerns about the safety of carry-in events.

“I think it’s too soon to see that,” Bernstein said. “But I do think it will happen. I think more companies will decide that a carry-in is not the best way to go for these events.”

He and his staff transport food in coolers or warmers to make sure it’s kept at proper temperatures, and keep extra utensils on hand to cut down on the risk of cross-contamination between food items, Bernstein said.

Public Health officials are asking that anyone who became ill after attending the Neff’s picnic July 3 contact them at 937-225-4460 to report their illness.