Guest blogpost from Peter Flegg, UK doctor.
This week I discovered a new toy to play around with. It’s the new interactive section of the Health Protection Agency website, called Health Protection Profiles.
With it, one can access several interactive maps and data tables covering a range of issues relevant to Health Protection in England. This includes data on vaccination uptake and the incidence of various infections.
Looking at the section on MMR vaccination was enlightening. As you may recall, in 2008 there were widespread outbreaks of measles throughout the UK, mainly because of low MMR vaccination uptake rates and poor levels of herd immunity. As a consequence, measles was declared to be endemic in the UK once again, and many Health Authorities had to implement catch-up vaccination drives to try and get as many unvaccinated children immunised as possible to avert further spread of disease.
So what is the current state of England’s MMR vaccination campaign? MMR vaccine is given twice in infancy, the first injection just after the child turns one year old, and the second one given between 3 and 5 years of age. Using the Health Protection Profiles information, one can see that the latest available data for 2009 show the national average for MMR uptake is as follows:
• Percentage uptake of 1st dose of MMR by 2 years = 84.9%
• Percentage uptake of 2nd dose of MMR by 5 years = 78.0%
You may recall that for measles, the required level of herd immunity within a population to provide decent protection against outbreaks of infection is over 90%. As not everyone who is vaccinated will develop fully protective immunity (there is a small “failure rate” for the measles component of MMR vaccine), this means that we should be aiming to achieve around 95% vaccine uptake to ensure adequate herd protection. Clearly there is still a very long way to go, as the detailed data indicate (around 17% improvement to be precise).
In London, where vaccination rates are traditionally lowest, the uptake of both MMR shots by the age of 5 ranges from a dismal 32% in Brent to a still inadequate 82% in Barnet. The main region of low vaccination is in North London, encompassing the boroughs of Brent, Haringey, (City and) Hackney, Camden and Islington, all of which struggle to even reach a 50% vaccination rate.
This continued failure to get our country’s infants adequately protected is a recipe for future measles outbreaks and potential disaster. That fewer than half the children in some areas of London remain either unvaccinated or incompletely vaccinated will mean a gradual build-up of the pool of susceptible children in these areas, and I predict that in 2 or 3 years time, further measles outbreaks will sweep through the city unless the vaccination rates improve.
Whilst the derisory national vaccination rates that were seen about 8 years ago can be blamed on the scurrilous scaremongering that followed Andrew Wakefield’s discredited notions about MMR and autism, it is clear that this is not still the reason for the continued abysmal vaccine uptake rate we see today. Only a tiny proportion of the public still believe in the “MMR causes autism” myth, though there may be a larger minority who still feel that vaccines are vaguely risky in some nonspecific way. MMR vaccine refusal rates were around 2% in one recent USA survey, an indication how the American public has not yielded significantly to the anti-vaccine scaremongers.
I haven’t seen a comparable survey for the UK, but I suspect that the results would be broadly similar. The anti-vaccine lobby in the UK is quite vociferous, but in reality it is nothing more than the mouse that roared, and its direct influence on the decisions of North London parents about vaccines must be minimal. But in 2009 fully two thirds of the children in Brent are not being adequately vaccinated against measles, which indicates something else is at work other than a conscious and deliberated refusal by parents on the grounds of possible vaccine risk.
The Health Protection Profile maps for MMR vaccine uptake in London in 2005 (when the scares about MMR and autism were still rife, though starting to recede) indicate that it was the more affluent areas like Kensington and Chelsea, and boroughs south of the Thames which had the lowest vaccination rates, while the areas in North London had relatively high rates (Brent actually having the 4th highest uptake at 71%). So what is going on?
The wretched vaccination uptake in these London boroughs is likely to be linked to the high indices of social deprivation and resultant erratic or even non-existent contact with health services, and things would appear to be getting worse, rather than better. Something needs to be done to re-engage with families/parents, and quickly, to establish suitable opportunities to offer vaccinations and other aspects of relevant health care. New and wide-ranging strategies will need to be developed and deployed, and I hope someone in authority is working on the problem as I write.
Introduction of combination vaccines has been shown to significantly reduce the risk of missing vaccines, and parents generally find this convenient and unthreatening to their child’s health. The recent announcement of a change in UK vaccination scheduling to give MMR, pneumococcal (PCV), meningococcal (MenC) and Haemophilus influenza B (HiB) vaccines at the same visit at one year of age rather than at 2 separate visits will undoubtedly help, but I fear a lot more work will need to be done in basic health care access and availability in the London boroughs if we are to avoid further outbreaks of disease.
In 2012 the Olympics will be coming to London. I predict that unless vaccine rates improve, the thousands of tourists and visitors coming to see London and the games will be entering a measles-endemic city that is rife with outbreaks of measles. Not only will we see children in the UK sickening and possibly dying, but the UK will serve (as it has done in recent years) as a source for the spread of measles around the rest of the globe (which does a damn sight better than us at vaccinating against this potentially serious disease).