Thursday, August 9, 2012

Checking the resurgence of pertussis

- Kenny Lin, MD

According to several news stories, more than twice as many cases of pertussis (whooping cough) have already been reported in the U.S. this year than in all of 2011. Although some of the disease resurgence may be due to increasing rates of vaccine refusal, experts are concerned that another culprit may be waning immunity from the acellular pertussis vaccine that has been used in the U.S. since the 1980s. Although a recent Cochrane review concluded that acellular pertussis vaccines (preferred due to their lower incidence of side effects) were as effective as whole-cell vaccines, the review relied mostly on indirect comparisons and limited follow-up intervals. In contrast, an Australian study published in the August 2nd issue of JAMA found that acellular vaccines were clearly inferior to whole-cell vaccines in preventing pertussis 10 to 12 years after vaccination.

In order to prevent new pertussis infections, especially in infants who are too young to be immunized, all adolescents and adults should receive Tdap immunizations instead of the traditional Td booster. To encourage patients to receive age-appropriate immunizations, parents should be counseled about vaccine safety, and standing orders and patient reminders instituted to prompt physicians and support staff when immunizations are recommended. Additional information on immunizations for pertussis and other vaccine-preventable diseases is available in the AFP By Topic collection.