These are alarming statistics, but here’s something more concerning: experts say the virus is so advanced, it’s at risk of becoming a superbug.
University of New South Wales microbiologist Dr Laurence Luu is calling for a new vaccine to combat the highly-contagious respiratory infection, as his research shows the bacteria is learning to survive in hosts – whether immunised or not. He shared these world-first discoveries in the medical journal Vaccine, published today.
"We found the whooping cough strains were evolving to improve their survival, regardless of whether a person was vaccinated or not, by producing more nutrient-binding and transport proteins, and fewer immunogenic proteins which are not targeted by the vaccine," he said.
"This allows whooping cough bacteria to more efficiently scavenge nutrients from the host during infection, as well as to evade the body's natural immune system because the bacteria are making fewer proteins that our body recognises.”
“Put simply, the bacteria that cause whooping cough are becoming better at hiding and better at feeding – they're morphing into a superbug,” he continued. Because of this, it’s now possible for a vaccinated person to contract the bacteria involved, without showing any signs or symptoms.
"So, the bacteria might still colonise you and survive without causing the disease – you probably wouldn't know you've been infected with the whooping cough bacteria because you don't get the symptoms," he explained.
"Another issue with the vaccine is that immunity wanes quickly – so, we do need a new vaccine that can better protect against the evolving strains, stop the transmission of the disease and provide longer-lasting immunity."
While Dr Luu would like to see this new vaccine developed in the next decade, he stresses that the current vaccine isn’t void yet.
"It is critical that people are vaccinated to prevent the spread of whooping cough – the current vaccine is still effective for protecting against the disease – but new vaccines need to be developed in the long-term," He said.
"We need more research to better understand the biology of the whooping cough bacteria, how they cause disease and what proteins are essential for the bacteria to cause infection so that we can target these proteins in a new and improved vaccine. This will all help to future-proof new vaccines against the evolving whooping cough strains."