Whooping cough is one of the most infectious diseases in the world

Whooping cough is more contagious than influenza, measles or COVID-19 and, once infected a person can remain contagious for three weeks or until they receive a course of antibiotics. 

 Symptoms of whooping cough don’t appear immediately (often a week or more following infections), so an infected person may unwittingly spread whooping cough to up to 17 unvaccinated people.