SAN JOSE (CBS SF) — At least 80 people have been sickened with an infectious diarrhoeal disease after eating at a Mexican seafood restaurant in San Jose, health officials announced Tuesday.

The number of sickened has doubled since it was first announced people had developed Shigella – marked by fever, abdominal pain and diarrhea after eating at Mariscos San Juan restaurant at 205 N. Fourth St. on Friday or Saturday.

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A majority of the 40 originally reported ill needed hospitalization and a dozen people were sent to an intensive care unit, according to the Santa Clara County Public Health Department.

Laboratory tests have confirmed at least 15 of the cases were Shigella and more results are expected to see if there are more people with the bacterial disease, public health officials said.

Symptoms of shigellosis develop one to two days after exposure and last for about five to seven days, according to public health officials.

Most people who suffer from Shigella make a full recovery but it can take months before their bowel habits return to normal, public health officials said.

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The disease is spread when people eat or drink something that came to contact with the stool of a person with Shigella, public health officials said.

Investigators are looking into what caused the contamination and suspect the disease might have spread through an ill food handler, according to public health officials.

“We urge anyone who is ill to seek medical care and to take steps to not spread the infection further. Meticulous hand washing by those who are sick is critical,” county health officer and public health director Dr. Sara Cody said in a statement.

“Our thoughts are with those who are sick as we work to prevent any further illnesses,” she said.

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