It is difficult to share the authors’ optimism that increasing primary immunisation above 92.9% might control this infection, given that it is a relatively poor vaccine and that whooping cough is most infectious before the characteristic cough can be recognised. Pertussis is here to stay.
In the UK the original whole cell vaccine was introduced haphazardly in the 1950s to combat the large number of deaths in childhood. It was very effective in this although some of the reduction can be attributed to improved social conditions. I do not believe there was any expectation of eliminating B. pertussis, whooping cough being a disease mainly of childhood but understood to affect all ages by a generation of doctors now dead.
We were reminded of the effectiveness of the vaccine in the 1970s and 1980s when vaccine acceptance fell by about half and large outbreaks occurred which I was able to study (1,2). In the aftermath of these outbreaks there was a remarkable drop in notifications as a new generation of GPs slowly took over who never knew the characteristic sound of whooping cough at a time when confirmation was only possible by impracticable per-nasal swabs. Meantime, my own practice was diagnosing and verifying pertussis at 30 times the national rate from 1995 to 2006 (3).
Pertussis toxin antibody elevations, and later PCR became standard testing methods, so unsurprisingly, laboratory confirmations, (which supplanted notifications in the UK) increased, giving rise to what is currently referred to as the ‘resurgence’ of pertussis. It is given rationality by the less effective purified vaccines introduced roughly around the millennium. I believe that much of the ‘resurgence’ is a consequence of easier testing.
The epidemiology of pertussis in the vaccine era is not well understood. Neither natural infection nor whole cell vaccine approaches lifelong protection and the various purified vaccines now used are confirmed to be less effective than whole cell vaccine. It is now known that asymptomatic pertussis infections occur and regularly boost immunity. The extent to which they enhance general population protection is unknown, but it may be considerable. The current large increase in cases, which seems to be a global and synchronous phenomenon occurring after the covid lockdowns, hints that intercurrent exposure to pertussis bacteria might play a significant immunity boosting role.
Most deaths occur in infants before they can be immunised. This changed dramatically in 2012 with the introduction of antenatal pertussis boosting. Virtually no childhood deaths need now occur but clinical whooping cough is very different matter. It is the severe end of the pertussis infection spectrum and is seriously under-diagnosed, largely because it is not suspected. There are no physical signs in uncomplicated cases and the severe paroxysms are hours apart. Knowing this caused me to create an information and advice website in 2000 (4) which is still confirming the misery and frustration of patients knowing they have pertussis but that possibility being denied by their doctors who refuse to test them. Mature adults with severe pertussis truly believe they are dying. Only time will cure it, but a diagnosis of a benign disease brings enormous relief.
Whooping cough will continue to be quite common from time to time until the anticipated nasally administered vaccine arrives. The existence of whooping cough needs to be better known and acknowledged. If the current high numbers reflect increased awareness and testing, this may indeed be coming about.
References
(1) Natural course of 500 consecutive cases of whooping cough: a general practice population study. BMJ 1995;310:299https://doi.org/10.1136/bmj.310.6975.299
(2) Outbreak in the Village. A Family Doctor’s Lifetime Study of Whooping Cough. Springer Nature Switzerland AG 2020. ISBN 978-3-030-45484-5
(3) Whooping cough is quite common and can be diagnosed clinically. BMJ 2006; 333 doi: https://doi.org/10.1136/bmj.333.7563.352
(4) https://whoopingcough.net
Rapid Response:
Re: Whooping cough rises sharply in UK and Europe
Dear Editor,
It is difficult to share the authors’ optimism that increasing primary immunisation above 92.9% might control this infection, given that it is a relatively poor vaccine and that whooping cough is most infectious before the characteristic cough can be recognised. Pertussis is here to stay.
In the UK the original whole cell vaccine was introduced haphazardly in the 1950s to combat the large number of deaths in childhood. It was very effective in this although some of the reduction can be attributed to improved social conditions. I do not believe there was any expectation of eliminating B. pertussis, whooping cough being a disease mainly of childhood but understood to affect all ages by a generation of doctors now dead.
We were reminded of the effectiveness of the vaccine in the 1970s and 1980s when vaccine acceptance fell by about half and large outbreaks occurred which I was able to study (1,2). In the aftermath of these outbreaks there was a remarkable drop in notifications as a new generation of GPs slowly took over who never knew the characteristic sound of whooping cough at a time when confirmation was only possible by impracticable per-nasal swabs. Meantime, my own practice was diagnosing and verifying pertussis at 30 times the national rate from 1995 to 2006 (3).
Pertussis toxin antibody elevations, and later PCR became standard testing methods, so unsurprisingly, laboratory confirmations, (which supplanted notifications in the UK) increased, giving rise to what is currently referred to as the ‘resurgence’ of pertussis. It is given rationality by the less effective purified vaccines introduced roughly around the millennium. I believe that much of the ‘resurgence’ is a consequence of easier testing.
The epidemiology of pertussis in the vaccine era is not well understood. Neither natural infection nor whole cell vaccine approaches lifelong protection and the various purified vaccines now used are confirmed to be less effective than whole cell vaccine. It is now known that asymptomatic pertussis infections occur and regularly boost immunity. The extent to which they enhance general population protection is unknown, but it may be considerable. The current large increase in cases, which seems to be a global and synchronous phenomenon occurring after the covid lockdowns, hints that intercurrent exposure to pertussis bacteria might play a significant immunity boosting role.
Most deaths occur in infants before they can be immunised. This changed dramatically in 2012 with the introduction of antenatal pertussis boosting. Virtually no childhood deaths need now occur but clinical whooping cough is very different matter. It is the severe end of the pertussis infection spectrum and is seriously under-diagnosed, largely because it is not suspected. There are no physical signs in uncomplicated cases and the severe paroxysms are hours apart. Knowing this caused me to create an information and advice website in 2000 (4) which is still confirming the misery and frustration of patients knowing they have pertussis but that possibility being denied by their doctors who refuse to test them. Mature adults with severe pertussis truly believe they are dying. Only time will cure it, but a diagnosis of a benign disease brings enormous relief.
Whooping cough will continue to be quite common from time to time until the anticipated nasally administered vaccine arrives. The existence of whooping cough needs to be better known and acknowledged. If the current high numbers reflect increased awareness and testing, this may indeed be coming about.
References
(1) Natural course of 500 consecutive cases of whooping cough: a general practice population study. BMJ 1995;310:299https://doi.org/10.1136/bmj.310.6975.299
(2) Outbreak in the Village. A Family Doctor’s Lifetime Study of Whooping Cough. Springer Nature Switzerland AG 2020. ISBN 978-3-030-45484-5
(3) Whooping cough is quite common and can be diagnosed clinically. BMJ 2006; 333 doi: https://doi.org/10.1136/bmj.333.7563.352
(4) https://whoopingcough.net
Competing interests: No competing interests