MADISON (WKOW) -
A Milwaukee health official questioned the effectiveness of the whooping cough vaccine this week, telling the Milwaukee Journal Sentinel newspaper that more than 90-percent of the Milwaukee children known to be infected in the city's latest outbreak were up-to-date in their vaccinations.
Dr. James Conway, a pediatrician at UW Hospitals and Clinics and expert on pediatric infectious diseases, says doctors have known for some time the whooping cough vaccine doesn't offer complete protection.
"The perception that the vaccine is losing effectiveness," said Dr. Conway. "Well, the vaccine hasn't really changed in particular. What we're understanding, as we do better surveillance, is the breadth of the kind of protection you get from these vaccines."
There are two vaccines for pertussis. The DTaP, for infants and toddlers, and the TDaP, which is a booster for people who spend time around infants and children. It's recommended for kids entering middle school and high school, as well as daycare and healthcare providers, parents and grandparents.
"The response to these vaccines is variable, Conway says. "Some people have a great response, some people have a partial response. The problem is that even though you have some immunity, you can still catch these disease.
Which could explain why many school-age kids are getting pertussis in Wisconsin, despite getting immunizations and the recommended booster. But because they've been immunized, they may have a milder case; more like cold symptoms. Plus, that TDaP booster their parents got years ago could be wearing off.
"It's only been recommended one does for a lifetime at this point," said Diane McHugh, with Madison and Dane County Public Health. "They're studying it all the time, and they know that it wears out in its effectiveness."
Which Dr. Conway believes could lead to a change in T-Dap recommendations in the future.
"I would anticipate that, similar to what we do every 5 to 10 years with tetanus boosters for people," he says. "That at some point we'll probably just continue to use this new tool and keep boosting people when they get their tetanus shot and give them a little whooping cough boost, as well."
