The number of whooping cough cases have tripled in Suffolk County since last year, according to the Suffolk County Health Department.
In 2010, there were only 54 reported cases of whooping cough. In 2011, there were 179 reported whooping cough or pertussis cases.
One reason for the increase, according to Suffolk Health Commissioner Dr. James L. Tomarken, may be because whooping cough is now better diagnosed and because public awareness is higher.
Another reason may be because more people are opting not to have their children vaccinated.
"It's a cyclical thing, sometimes we see pertussis in waves of three to five years," said Tomarken. "We hope we have seen the worst but we just don't know."
Whooping cough usually starts with cold symptoms, accompanied by a persistent dry cough that could last weeks or even months. The bacterial infection is spread through droplets in the air.
Of the 179 cases in Suffolk so far this year, almost 40 of the patients were students in the Smithtown school district. In June 2010, nearly 40 people, most of them students, contracted whooping cough.
According to Suffolk health officials, all those affected had been immunized in the past, but immunizations are not 100 percent effective. The students did develop less severe symptoms because of their prior vaccinations.
"Parents should make sure their children are getting booster shots," said Dr. Tomarken. "And adults who are in contact with any child under one, should also do the same."