Ahem. Cough, Cough, COUGH, Choke, Whoop!

Bordetella Pertussis is a very small Gram-negative aerobic coccobacillus causing the highly infectious disease whooping cough, cause of significant infant mortality before the advent of cellular vaccinations. It colonizes and reproduces on the cilia of the respiratory epithelium of mammals. The genus Bordetella contains the species Bordetella pertussis, Bordetella parapertussis, Bordetella bronchiseptica, Bordetella hinzii and Bordetella avium.

The little critter (2000 nanometer long) produces a number of proteins which attach it to the surface of our respiratory tract, most importantly filamentous hemagglutinin (FHA) and the pertussis toxin (PTx). It also produces a number of toxins preventing the host cellular defences from getting rid of it quickly: especially the above mentioned pertussis toxin and the nasty sounding lethal toxin (causing necrosis and inflammation) and the tracheal cytotoxin, preventing our ciliated respiratory cells from beating. This is of course a very clever pathomechanism which prevents the host from getting rid of the invader the easy way: it not only keeps the host body from throwing it out via it's motile cilia, but also initially stops the immunocompetent cells from gobbling it up.

Bordetella can be cultured from nasopharyngeal swabs on a charcoal-blood agar at 37 degrees celsius. Additionally to this there is a serological test, confirming the presence of antibodies in the patient.

Whooping cough epidemics seem to be running in a 2-5 year cycle (currently there seems to be one in North Otago, causing quite a number of infected individuals). The vaccination only gives you protection for 5-10 years, so young children can well be affected by the bacterium, even though vaccinated, so be aware.