Seroprevalence of pertussis among adults in China where whole cell vaccines have been used for 50 years

Our study showed that about 5% of adults aged 20-39 years had positive anti-Ptx IgG antibodies, suggesting that adult pertussis is common in China. Giving a booster vaccination to pregnant women should possibly be considered in order to protect young infants who are too young to be vaccinated in this country.