Public health officials across the region say cases of whooping cough are on the rise.
The signature sound of whooping cough — or pertussis — is a hacking wet bark that makes parents anxious and kids uncomfortable.
But Dr. Stephen Ostroff says sometimes the illness, especially in the early stages, is hard to distinguish for the common cold or other respiratory illness.
“The whooping that gives whooping cough or pertussis its name is actually more common in younger children than it is in older children,” said Ostroff, director of the Bureau of Epidemiology at the Pennsylvania Department of Health. “And most adults who get pertussis do not have that whooping.”
There have been about 1,200 confirmed pertussis cases in Pennsylvania so far in 2012, about 200 more than in all of 2011.
There’s usually a lull in its spread when children are out of school, but not this year.
“The number of pertussis cases that we saw over the summer was not that much different from what we saw over the other months of the year. And one of our concerns is that now that school is back in session, we could see even increased cases from what we’ve seen over the last few months,” Ostroff said.
The commonwealth is on pace to log a record number of pertussis cases this year. Much of Pennsylvania’s upsurge is among children ages 8 to 12, and last year the state began requiring a pertussis vaccine for students entering 7th grade.
New Jersey has a similar requirement for adolescents, but there’s no mandate in Delaware.
Increase part of a cyclic pattern
Dr. Karyl Rattay, who leads Delaware’s Division of Public Health, said that historically there’s been a spike in pertussis cases every three to four years, and this year’s increase is on schedule.
It’s not clear what’s driving the increase in reported cases across the nation and in this region, but Rattay says improved diagnostic testing may be a factor.
“We are just able to diagnose more cases,” she said.
Another hypothesis is linked to a new vaccine formulation that first was distributed several years ago. Ostroff said there is a concern that the change may have reduced the efficiency of the vaccine, so the immunity that’s generated from a series of shots in childhood may wear off more quickly.
Still, health officials say, vaccination is the best protection against the disease. They are reminding adults — in particular those who spend time with babies — to make sure their “shots” are up to date.
“You are not really well immunized until you get your third dose,” said pediatrician Hal Byck. He cares for kids at a community medical center associated with A.I. duPont Hospital for Children.
“So those kids between birth and six months are always going to be vulnerable,” he said. “It’s so important that young adults and teenagers are well vaccinated, because they are the ones who can spread it to the babies that we are just not able to completely protect.”
Pertussis, a very contagious bacterial illness, is commonly treated with antibiotics.