Bacteria have been ruled out as the cause, meaning last weekend's outbreak linked to the Dinosaur Bar-B-Que is probably viral and could have spread through air particles, said Cynthia Morrow, health commissioner of Onondaga County.
The Centers for Disease Control and Prevention were notified because the people who may have been affected were from across the country, Morrow said. Patrons from as far away as Massachusetts, New Jersey, Vermont and California have reported symptoms.
Some were sickened after eating at the restaurant, while others became ill after being exposed to those who had, health officials said.
The most common symptoms include nausea, vomiting, diarrhea, abdominal cramps and chills lasting 12 to 48 hours.
The county health department on Thursday ordered the restaurant closed for at least 72 hours. Workers threw away hundreds of pounds of prepared foods. No specific foods have been implicated.
Restaurant owner John Stage said he plans to reopen Monday.