whooping cough

[jinx]

Bordetella pertussis Strains
with Increased Toxin Production
Associated with Pertussis
Resurgence

In the 1990s, a resurgence of
pertussis was observed in a number of countries with highly
vaccinated populations, and pertussis has become the
most prevalent vaccine-preventable disease in industrialized
countries. We present evidence that in the Netherlands
the dramatic increase in pertussis is temporally associated
with the emergence of Bordetella pertussis strains carrying
a novel allele for the pertussis toxin promoter, which confers
increased pertussis toxin (Ptx) production. Epidemiologic
data suggest that these strains are more virulent in humans.
data suggest that these strains are more virulent in humans.
We discuss changes in the ecology of B. pertussis that may
have driven this adaptation. Our results underline the importance
of Ptx in transmission, suggest that vaccination may
select for increased virulence, and indicate ways to control
pertussis more effectively.