"Whooping cough is caused by a bacteria called Bordetella pertussis. Pertussis often begins like most other respiratory infections, with typical symptoms including a runny nose and a fever. The distinctive "whoop" cough may only appear after a week or so of illness – though it does not occur in all cases. As such, confirming cases of whooping cough may require a laboratory test.
Whooping cough is very infectious. On average, a single case of pertussis can transmit infection on to around 15-17 other people. This infection rate is similar to measles and higher than the COVID variants.
The reason whooping cough is so infectious is in part due to pertussis having a very long infectious period of up to five weeks – where infected people can pass the bacteria on to others. Prompt treatment can greatly reduce transmission – antibiotics shown to reduce contagiousness just five days after starting treatment." https://flipboard.com/@sciencealert/health-43m5auulz/-/a-DibHQr-dQdupkv4ryPjYvA%3Aa%3A565656366-%2F0
