Whooping cough may be evolving to resist vaccinations. That would be bad.
Analysis of strains from 2012 shows the parts of the pertussis bacterium that the vaccine primes the immune system to recognise are changing.
It may have “serious consequences” in future outbreaks, UK researchers state in the Journal of Infectious Diseases.
But experts stressed the vaccine remains highly effective in protecting the most vulnerable young babies.
There has been a global resurgence of whooping cough in recent years.
In 2012, there were almost 10,000 confirmed cases in England and Wales – a dramatic increase from the last “peak” of 900 cases in 2008.
The outbreak led to 14 deaths in babies under three months of age – the group who are most vulnerable to infection.
The BBC doesn’t make clear whether researchers think that dramatic increase is due to the new resistance as well as or rather than reduced rates of vaccination. I guess I should read the Journal of Infectious Diseases to find out.
Prof Adam Finn, a paediatric immunology expert at the University of Bristol said the importance – or not – of the subtle changes found in the study was as yet unclear.
“But the control of pertussis is a significant worry,” he added.
Only 60% of pregnant women have had the pertussis vaccine and we should be doing more to raise awareness of its benefits, he said.
“There is very good new evidence that vaccinating pregnant women protects their babies. And the group we really want to protect is newborn babies,” he said.
Because pertussis can kill newborn babies all too easily.
Pertussis is a bit of a clinical outlier. Unlike many of the other illnesses prevented by vaccination (but similar to things like tetanus), it appears that pertussis immunity is not life-long. Cyclical outbreaks of adult pertussis have been fairly constant over the last few decades so there is probably a greater natural reservoir of the pathogen.
…and newborns cannot receive the immunization.
Part of the problem is that the old whole-bacterial-cell vaccine, DTP, gave a longer-lasting immunity, but was erroneously thought to cause serious neurological side effects. It was reformulated to the current TDaP (the “a” stands for “acellular”) to minimize that possibility, but its shorter effective life has only recently been discovered.
Due to an increase in friends having babies I had my booster recently.
I saw a report earlier this year of a vaccine resistant polio in Africa.
Bless you, Ariaflame. I mean it. One of my closest friends had his 3 month old son come down with pertussis. That baby spent the next 3 months in the hospital, very nearly died twice, and has permanently damaged lungs. I strongly urge everyone older than about 40 to do the same thing. It would kill me if I thought I was the one who passed that damned disease on to that poor baby.
I was lightly involved in the development of the acellular whooping cough vaccine and it’s a tricksy beast of a bacteria that’s been driving microbiologists crazy since it was isolated. Instead of the relatively easy protein targets of viruses and many bacteria it has a complex polysaccharide coating that has to be targeted.
Some countries have never introduced the acellular versions – it would be educational to see if they are seeing the same antigenic drift.
However, swapping out a few antigens, or adding some, would be relatively easy to do. Reverting to whole-cell would be even easier, and perhaps for some populations would be best. Boosters for adults, for example.
@1 … it’s becoming obvious that the “lifelong” immunity for many of the vaccine preventable diseases was the result of repeated exposure to the pathogens acting as a booster, and having the anamnestic response take care of the infection before you have any symptoms.
You get measles as a toddler … immunity begins … you are exposed to the measles in 3rd grade, get infected but not ill because your immune system leapt into action, get the equivalent of a booster … lather rinse and repeat as others in your environment get sick and spread pathogens.