In December 2008, the World Health Organisation (WHO) announced that measles immunisation programmes have reduced the annual number of deaths to about 200,000 globally over the past decade (from 750,000).
In January 2009, the Health Protection Agency (HPA) announced that the incidence of measles cases in England and Wales had reached the highest for more than a decade.
One hundred years ago deaths from measles were commonplace: the equivalent of more than 10,000 per year, given today’s UK population. As public health and hygiene gradually improved this mortality rate fell, but by the time an immunisation programme was launched in the UK in 1968, there were still about 100 deaths each year. The immunisation programme had an impressive impact and deaths from measles became rare. Most of the subsequent deaths have been attributable to long-term complications.
Over the past four decades, we have gradually forgotten what measles is really like. The overall rate of complications is high and was 6.7% before the introduction of the measles vaccination. Encephalitis affected 1.2 in 1,000 measles patients.
Having been just young enough to be an early beneficiary of the newly-launched measles immunisation programme, I was unfortunately just old enough to have had the opportunity to develop natural immunity. I never needed the vaccine and fortunately I never suffered the complications. Others were not so lucky.
For those of us who know people who developed encephalitis and have endured the consequences for decades, the toll of measles is a constant reminder. For many measles is just a childhood disease of the past, but globally, measles remains an important killer.
On the increase
The past year has seen the highest number of measles cases for many years. Urgent programmes have been launched by primary care trusts. In Cheshire, for example, a recent catch-up campaign has targeted 10,000 unprotected children in more than 200 schools. The success of this campaign has not been reported, but many parents have still declined to immunise their children.
Units supporting those who care for sick and vulnerable children have had to check their policies and audit the immunisation of workers. Just as the HPA has warned that “we may see measles epidemics take hold”, we should be concerned that measles could again become an important occupational disease, with significant short and long-term morbidity.
Measles is not the only old adversary that was almost eradicated by immunisation but is making a comeback. The incidence of tuberculosis has increased almost incessantly over the past decade, and reports of whooping cough also rose again last year.
Other important occupational infection hazards are increasingly important. The incidence of HIV has not decreased, and the population of people living with the disease continues to grow steadily. New reports of hepatitis C and the prevalence of the disease also continue to rise. Infections of occupational importance regularly make national news stories, including MRSA, C Diff, legionella disease, and influenza.
All of these infectious diseases have a noteworthy mortality rate. This is in stark contrast to the absence of a mortality rate associated with almost all musculoskeletal disorders and common mental health problems.
When it comes to infectious disease, the contrasting news headlines can lead us only to conclude that we have forgotten the lessons of the past. Our performance is in decline. 2009 should be the year we give the prevention of occupational infection the priority it deserves.