It is ten years since Andrew Wakefield had his now-discredited paper on the MMR jab, published in the Lancet. This paper sparked off a scare that the vaccine caused autism in children and many parents opted out of the jab, going for single vaccines instead, or not having their children vaccinated at all. The scare reached its peak in 2002 and it was two more years before it was thoroughly debunked by Brian Deer, a Sunday Times reporter. But the damage had been done and now unfortunate parents and their children are rediscovering that measles cause corneal scarring,deafness, croup and encephalitis(inflammation of the brain).It is one nasty disease and Andrew Wakefield bears a heavy responsibility for the new outbreaks of measles that have been recently reported.
However, there may be another element to this rise in measles, and that is the way in which data collection for communicable diseases changed in 2002. Before 2002, COVER statistics (Cover of Vaccination Evaluated Rapidly)were collected from computerised child health systems, which record what a child has been vaccinated against. These figures were then compared to the size of the health authority or trust population. This told the health authority how many children had been vaccinated, and vitally, how many had been missed or had gone unregistered. In 2002, when primary care trusts were introduced, the same method of collection was used, but the denominator changed from the size of the trust population, to the size of the population registered with a GP practice and residence for unregistered patients. This resulted in a near 100% vaccination record for measles and other diseases. However, when a researcher called Julia Granerod compared the vaccination statistics with population figures from the Office of National Statistics, she found that there was a discrepancy. She estimated that for 1998 - 2001, 10-20 000 children per annum had gone unregistered; in 2002, between 20 -40 000 children had gone unregistered and in 2003, the figures had dropped back to 2- 8000 children unregistered. This is vital information that is missing from the main statistics, and at a time when outbreaks of measles are happening, it is very worrying. Particularly worrying is the 2002 statistic. In the Granerod paper it was assumed that this blip was due to the re organisation of the trust areas, and a delay in registering people with the appropriate trust. But 2002 was the year that the MMR scare was at its height; it may be that these children were actually not vaccinated as opposed to being simply unregistered. These figures need analysed as a matter of urgency, and the Department of Health needs to re-consider how it is measuring vaccination uptake. Otherwise it could find itself in the middle of a major outbreak without the essential data to counter it.
