|October issue of Microbe, published by ASM.|
I read a very interesting—and somewhat alarming—article in the October issue of the journal Microbe (formerly ASM News). In this article, Merry Buckley explains that whooping cough (aka pertussis), a childhood disease that has strongly declined since the introduction of a vaccine in the 1940s, is now on the rise again. We even see epidemics! says Buckley.
In 2012, in the USA, the number of pertussis cases is expected to be the highest in fifty years, approaching 40,000. Other countries such as Australia and the Netherlands also have high incidence of the disease—in the Netherlands, 6,000 cases were reported in 2009, against only 30 cases in 1980. The causes of this comeback are not fully understood, but scientists have gathered many clues.
Whooping cough is caused by Bordetella pertussis, a Gram negative bacterium belonging to the group beta Proteobacteria. It infects the respiratory system, causing a characteristic ‘whoop’ sound in sick children. Teens and adults can also be infected, although the symptoms are milder than in small children. In the prevaccine era, pertussis was a terrible threat, killing on average 5,000 children a year during the 1920s and 30s in the USA alone. At this period, the epidemics peaked following a cyclic pattern of a couple of years.