The Keyworth study
Page updated April 2015
The information on this website is based on the study of whooping cough that I have undertaken as a family doctor over 35 years in Keyworth. Much of the material has been published in medical journals. Some is unpublished, and some is my opinion based on experience. I believe this is a unique study and that I have a contribution to make to the understanding of this unpleasant and sometimes lethal disease.
I wish to make my data available to the public so they may judge its value for themselves. This page outlines the main findings for the interested layman.
Keyworth is a village about 5 miles south of Nottingham in central England. It has a population of 8,000. There are several smaller nearby villages and all together make up a community of about 11,000, that all come under the care of 8 family doctors working from a single medical centre. 30 years ago there were 11,800 patients and 4 doctors)
I have worked at Keyworth Health Centre since 1974, when I started as the most junior partner after returning from 3 years in central Africa where my research interests developed. Since 1977 I have made a special study of whooping cough in this small population (over 720 cases). I have developed the ability to recognize cases that most other doctors would miss, simply because of my intense interest in this disease and being on the lookout for it all the time. Because of the way healthcare is organized in England, with single medical records and patients registering with one medical centre only, it is possible for me to be confident that what I observe about whooping cough in Keyworth, is as complete as possible, accurate, and most of all, consistent.
I retired from the partnership in 2011 but was able to reliably follow the incidence until 2013. Since then it has not been possible to continue the study with the previous thoroughness and therefore the study offiicially ended then.
It has become even more important to continue in the same way because serological diagnosis has become mandatory as the HPA now uses laboratory confirmed cases for its statistical baseline. As the age of victims has climbed to an adult age, so the ease of getting a blood test increases. Blood tests have only been available since 2006 in the UK. Increasing familiarity with the need for the test and increased awareness and self diagnosis by the now adult victims by means of the internet (and this site in particular), has led to a massive rise in the proportion of suspected cases that are getting confirmed, and number of tests being done. Previously they would not have been tested by pernasal swab which is difficult to arrange and uncomfortable. As well as usually being negative because it was too late in the illness. So theywould hardly ever be notified.
Because we are just an average medical practice, what I have observed in Keyworth is also probably representative of what happens in the rest of the United Kingdom. It may also be quite similar to what happens in other developed countries with similar immunization practices (for example: USA, Canada, Australia, New Zealand and the countries of the European Union.
What is the point I am
What are the general observations that can be made from the Keyworth study?
1. Keyworth appears to have about 30 times as much whooping cough as the rest of the country! This may be changing as in 2012 we only notified 10 times as many!
2. About a third are in teenagers and two thirds are in adults. This has changed from 90% in children 35 or so years ago
3. Although outbreaks seem to occur generally (in the country) every 4 to 5 years and last about 18 months, it is common to observe (at these outbreak times), small outbreaks affecting a single school, for instance, over a period of a few weeks or months, the general upsurge being made up of lots of little ones. (This has not been seen in Keyworth for a decade or so now.)
Why is this relevant?
Since immunization came in the 1950s, doctors have seen less and less whooping cough and modern doctors may never have seen a case, let alone heard the cough. I believe that much of the drop in notifications has simply been a reflection of the poorer diagnostic skills of modern doctors in respect to whooping cough. Now that some people are looking for it with more sophisticated tests such as PCR, blood antibody, and recently saliva antibody tests, they are finding it, but still notifications are very low, as the average doctor is still reluctant to diagnose it.
The crux of the issue is the number of cases diagnosed in Keyworth (1977 to 2012) compared with the rest of the country (for administrative purposes this is England and Wales). The figures show that national notifications have got less and less over the years, while the Keyworth figures have remained fairly constant (allowing for the 4 to 5 year cycles). On average, in Keyworth, we notify about 30 times as many cases as other doctors.
Raw data (anonymous) from this Keyworth study along with tables and graphs have been made available on this site in order that health care workers, epidemiologists and interested others can study the detail. www.whoopingcough.net/keyworth