Whooping cough is a kids disease? That is the public perception and one docs might believe as well.
We have had an epidemic of B. pertussis in WA this past few months, despite pretty good vaccination rates – so where does this bug come from?
There is a large pool of whooping cough in the adult / older child population, and that is where the babies get it – and get sick. So how do we go about fixing this problem?
I did a bit of reading and found that the rate of Pertussis in adults is actually alarmingly high – these trials ( BMJ 2006, school kids, Clin Vacc Immunol 2010 , Jour Infect Dis 2002 from France. ) show that if you take a patient presenting with a cough of > 2 weeks and swab / test them all between 12 – 37% will test positive. So by just taking a history – “cough for 2 weeks” you have a pre-test probability of about 25% for a disease that you really want to treat ASAP to decrease the risk of transmission to some innocent neonate / infant. You might say – “why bother doing the test “- you are going to treat them anyway. But we do the test to confirm and allow our Public Health colleagues to get a grip on the outbreak.
The pertussis vaccine is possibly the shortest effective duration of all vaccines on the schedule. Having had a course is not protective into later childhood or adulthood. In WA the government have been running a campaign to get all new parents, and expectant grandparents vaccinated to try and close the risk of friendly fire from within the new family unit.
I think as healthcare providers we need to be vigilant and consider this diagnosis in patients with a prolonged cough and be prepared to treat and ask the patient to isolate themselves from small infants.