The diner was closed throughout Mother's Day weekend because of the situation.
"We have made the decision to close again on Monday in an effort to be as proactive as possible," said a representative of the diner.
Over the weekend, the diner brought in BioOne from New York City to completely sanitize the restaurant as it continued trying to find the origin of what made people ill, she said.
"We are going above and beyond to make sure that not one of our customers becomes ill," she said.
She also added that the virus or "illness" was not caused by any employees and that none of the employees are ill: "I not sure where that came from, but our employees are not ill."
On Facebook, the diner posted: "Right now, we have come back negative on every test however, we will continue to use all precautions and be proactive. As everyone knows, especially parents, viruses are extremely common in any public place and can be spread by person-to-person, contaminated surfaces or through the air. With hundreds of people coming in and out, it is near impossible to know where this virus could have started."
Fans of the restaurant posted their support for the diner that has served the area for more than 40 years.
Most lauded the steps taken to make sure the public is protected, although a few mentioned they had become ill after eating at the restaurant.
Westchester County Health officials are working with the diner to ensure all health-related rules are followed.
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