Senior Research Fellow in Global Health, Southampton University

UK public health data shows that not only are there almost 3,000 confirmed cases of whooping cough so far in 2024, there are now sadly five confirmed infant deaths.

This is a stark reminder that whooping cough is a serious infection – it can and does kill babies.

The illness is caused by a bacteria – Bordetella pertussis.

This large outbreak will in part be caused by lower vaccine uptake, along with a populationwide waning of immunity in individuals who were vaccinated several years ago.

The vaccine is extremely effective, and mimics the Bordetella toxins to produce a safe immune response. It protects younger children, but immunity does wear off after a few years. Many of the cases are in older children or adults.

Whooping cough is very infectious. It has an “infectious period” of two to three weeks – the period of time when an infected individual is able to transmit the bacteria to others.

With wet and cold weather, where people cluster indoors perhaps with little ventilation, there may be plenty of opportunities for transmission to occur and for there to be an infection of a vulnerable individual, such as a baby.

Vaccine uptake in young children and for expectant mothers during pregnancy is so important.

Similarly, a high coverage of vaccination across a population is vital in reducing communitywide transmission and thus protecting both individuals and those around them who may be vulnerable.