Moreover, adults and adolescents often wait weeks before seeking treatment for a chronic cough - and even then, doctors may not recognize it as pertussis.
"The scientific community back in the 1990s felt that it had pertussis solved," Halperin says.
The mechanism by which this occurs has not been fully elucidated; however, there is some suggestion that it is pertussis toxin-sensitive Gαi coupling (Schepp et al., 1992).
"Our focus now is on improving access to education, health and other services at the community level, and to ensure Liberia is better equipped to face future health threats, be it measles, pertussis or Ebola," said Yett.
At 7 positions between residues 133 and 166 it shares B. pertussis sequences, although it also harbours unique substitutions in that region.
As it is designed to reduce carriage and transmission of Bordetella pertussis, it may hopefully contribute to the ultimate control of pertussis.
"When very young infants get pertussis, it's usually from someone in their own households," Dr. Clark said.
Interestingly, wP vaccination decreased O-antigen deficient B. parapertussis numbers as efficiently as it did B. pertussis numbers in the trachea and lung (Figure 1B).
In B. pertussis, it has been suggested that expression of the T3SS translocon Bsp22 is blocked by post-transcriptional regulation [18].
For more effective vaccination programs to prevent pertussis, it is important to understand pathogenesis and transmission of B. pertussis, to monitor changes in bacterial populations and to study impact of the changes on the prevention and incidence of disease.
