Health officials in both Nassau and Suffolk counties are asking parents to be vigilant due to a recent rise in whooping cough cases.

Experts say the infection poses the greatest risk to infants under 2 months old who are too young to be vaccinated.

Complications among infants can include pneumonia, brain damage and even death.

"The biggest risk in infancy is that they can develop what's called apnea, where they stop breathing, and that, obviously can have tragic consequences," said Dr. John Zaso, of the Nassau County Department of Health.

Zaso is also a pediatrician in East Meadow. He said he diagnosed two cases of whooping cough on Saturday alone. He said the number of whooping cough, or pertussis, cases in Nassau County has spiked in the last week. In Suffolk County, another 108 cases have been reported.

"You start getting into the hundreds, that's a big number," Zaso said. "For us it's enormous because you should be close to zero. These are vaccine preventable diseases."

The majority of cases are amongst school-aged children and their parents. The most common symptoms include cough, nasal congestion and fever.

Vaccine hesitancy is a big factor in the outbreak, according to Zaso. He wants to tell parents that the whooping cough vaccine is safe. He also wants to help parents recognize the signs and symptoms.

The bacterial infection starts out looking like a cold but after a week or two, a unique cough develops.

"The cough is very unique in the older kids, and while we call it whooping cough, is they'll cough, cough, cough, cough, they'll turn blue sometimes, and then they take a deep breath in and you create that high-pitched whoop," Zaso explained.

For healthy adults who have coughs they just can't get rid of, Zasos also advises for them to get tested.

Whooping cough is also treatable by antibiotics, but only if it's caught in the first three weeks.

Doctors advise for parents to be vigilant and get children, especially infants, to the doctor sooner rather than later.