Victorian cases of whooping cough, or pertussis as it is also known, jumped by more than 50 per cent in 2014 to 4614 reported instances.

Warrnambool recorded 18 cases last year, a slight reduction from 20 in 2013 but still higher than the 14 cases recorded in 2012.

Great South Coast Medicare Local immunisation advisor Alison Elliott said vaccination against the disease would this year be extended to students in years 7 through to 10, aligning Victoria with other states.

“The transition of dTp (diphtheria Tetanus pertussis) vaccine to year 7 will provide students with earlier protection from these diseases, compared to the former Victorian regime of booster vaccination in year 10,” Ms Elliott said.

A highly-infectious bacterial respiratory infection, pertussis can vary from mild to severe for adolescents and adults, and is potentially fatal for infants. 

It’s sometimes called the “100-day cough” because of its ability to persist despite treatment, with the common name coming from the “whoop” sound often made by child-sufferers as they gasp for air after a coughing fit.

A significant danger from the disease for infants is apnoea — a prolonged pause in breathing that can be damaging or fatal.