"Preliminary evidence from lab reports on stool samples indicate this is norovirus—a run-of-the-mill, GI illness that we see this time of year," Harford County Health Department spokesman William Wiseman told Patch.
The illness was transmitted from contact, so to avoid it: "Hand-wash, hand-wash, hand-wash," Wiseman said.
"This was clearly a matter of contagion from person to person and could have resulted from menus that were touched or bar or table surfaces or chair surfaces or doorknobs..." Wiseman said.
People who got sick reported becoming violently ill with nausea, vomiting, diarrhea and stomach pain.
"These things are virulent—they transmit very easily, [and] it's a rather resistant virus..." Wiseman said.
While many reported eating at restaurants before getting sick, Wiseman said: "...this is not a bacterial illness that would have suggested something in the way of contaminated food or tainted food." The cause was a virus.
Based on citizens' reports, health officials inspected several restaurants in Harford County and found that all were above board, he noted.
"I think there's all the reason to continue to enjoy the restaurants around the Harford County area," Wiseman said.
The takeaway for people is that they should wash their hands diligently.
"We’ve all been in restaurants where the person's method of hand-washing is regrettably nothing at all," Wiseman said, "or shorter than 5 seconds."
He suggested timing hand-washing to the lyrics of "Twinkle Twinkle, Little Star," or scrubbing for 30 seconds under the water.
He advised covering hands with soap, rinsing thoroughly and rubbing hands together because the abrasion gets germs away.
"We hope that everyone's taking precautions," he added, "and staying away from places if you're coming down ill."