Pertussis vax only good for a year: study
25th February 2016
The booster vaccine Tdap (dTpa) wanes rapidly and provides only limited, short-term protection against pertussis when administered to teenagers.
This is the surprise finding from a US study of more than 270,000 children who were followed from infancy to adolescence.
The results, based on 1207 pertussis cases, suggest dTpa may be more effective if administered