In light of recent outbreaks of pertussis, or whooping cough, in California and other states, health officials have renewed their emphasis on vaccinations against the illness — for both children and adults whose immunity may have waned over time.
But a new study suggests widespread adult vaccinations may not bring about the reduction in pertussis cases some had hoped. Researchers projected that, given the patterns of social mingling seen in Europe, even if 75 percent of adults received pertussis boosters — an unrealistic target, experts say — it would reduce cases by only 15 percent....