"The number one key to survival is to be able to isolate the cause fairly quickly and to demonstrate that the vulnerability has been totally eliminated," said Clark Wolf, chief of restaurant consulting firm Clark Wolf Co. "There can be no question in people's minds that something profound has happened."

The restaurant executives and staff must also be very open about what has happened and what has been done to fix it, he said.

"The public does accept that disease sometimes happens," he said. "But if it comes from general practices that haven't been changed, there's no way to overcome that."

“It’s more common than not for eateries to miss opening-day goals,” said Clark Wolf, president of the restaurant consultant Clark Wolf Co. There are all these licenses involved, and every city has a different bunch of quirks,” he said. It’s very easy to be over confident, especially when it comes to timing.”

 It might be better for a restaurant to wait for warmer weather to launch lunch service anyway, said restaurant consultant Clark Wolf, of Clark Wolf Co. in New York. That's when people are more likely to want to get out.

"Either you have a natural lunch location or it will be a slow build," he said.