NEW YORK (CBSNewYork) — A contagious bacterial infection is spreading fast in New York.

The shigella bacterium outbreak started in Brooklyn, but now parents are on high alert in Rockland County.

“What concerns me is maybe that my child might catch it, get sick, end up in the hospital,” said parent Debbie Griffith. “You know, you don’t want this thing to spread through schools.”

As CBS2’s Ilana Gold reported Saturday, the problems started in Borough Park where dozens in the Jewish community have been infected with shigella.

But doctors say some of the patients from the area have traveled to Rockland County and spread it to families there.

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“We began to see it spreading to other counties, not only Rockland as well,” said Dr. Oscar Alleyne, director of public health planning for the Rockland County Health Department.

Dr. Alleyne said the highly contagious bacterial infection has hit hard in Monsey and Spring Valley, affecting mostly children.

Dr. Alleyne knows of 17 confirmed cases in January and 49 total from November through December.

“To be honest, our boundaries are never really boundaries. People travel back and forth all the time.”

Dr. Alleyne said parents could have gotten the infection from those affected in Brooklyn. where 80 cases have been reported in Borough Park and Williamsburg since November.

Doctors say students could also be spreading it at school and then bring it home.

In the wake of the Rockland County outbreak, parents were on high alert.

“Now I’m going to be wiping stuff down more,” said Christine DeMasi of Spring Valley. “Hopefully, the parents will be careful about keeping their kids home and not spreading it around.”

“My 8-year-old daughter is up the whole night, every 15 minutes approximately,” said Yidel Perlstein.

Perlstein’s daughter got shigella last week.

“It’s really affecting people. It’s really a troubling situation,” he said.

Shingell attacks the digestive track. Symptoms include severe diarrhea, stomach cramps and fever, and the most severe cases involve convulsions and kidney failure.

The infection spreads through person-to-person contact, and direct contact with feces, or contaminated food or water.

At highest risk are children between 2 and 4 years old.

Health officials are now warning everyone to wash their hands thoroughly, saying this will help stop the outbreak from spreading.

The health department has sent an alert to people living in the affected communities.