Between January and the end of May 2002, there were 981 reported cases of measles in Campania, a region in southern Italy where only about 65 per cent of children are vaccinated against the disease. Thirteen patients developed encephalitis, which can cause brain damage, and three died. The last major measles outbreak in the region was in 1996.

Italian doctors have now revealed details of their investigation into the outbreak and say: "The epidemic in Campania has the characteristics of an epidemic in a population with intermediate levels of vaccine coverage - levels are high enough to increase the length of the inter-epidemic period, but too low to interrupt the transmission of the infection."

A 95 per cent measles vaccination rate is necessary for national immunity, says the WHO. Currently in the UK, just 84 per cent of children aged two years have received the MMR (measles, mumps and rubella) jab, down from 92 per cent in 1995. In London, the figure is now just 72 per cent.

"If this outbreak in Italy and the deaths of these poor kids has the effect of increasing uptake of the MMR vaccine in the UK, that might be a good outcome," says Natasha Crowcroft, a consultant epidemiologist at the UK's Public Health Laboratory Service.

"It's no surprise to us in the field that if vaccination slips, measles will come back. That's what it does. We don't want to scare anyone, but it's very hard to educate about the risks of measles when, as a result of a good vaccination programme, as in the UK, the deaths go away," she says.

Four-fold rise
 

Fears about a suggested link between the combined MMR vaccine and autism and bowel disorders in children were first raised in 1998. Parental concerns about the MMR vaccine have caused the recent UK drop in coverage, despite widespread backing for MMR from medical professionals.

The latest quarterly UK government data show that in the first quarter of 2002, the number of measles cases in the UK was 126 - four times more than in the last three months of 2001. This increase is mainly due to the continuation of an outbreak in south London that started in December 2001, the Public Health Laboratory Service says.

On Wednesday, Ken Livingstone, the Mayor of London, advised Londoners against giving their children MMR, and to opt for separate vaccines if possible. That advice was rejected by the Department of Health.

A British Medical Association spokeswoman says if vaccination rates drop to the level in Campania, "there will be deaths in the UK and other serious health problems like brain damage."

"Safe and effective"
 

Measles vaccination in Campania must now be stepped up, to prevent new epidemics, say the Italian investigators, involving members of the local Regional Health Services Agency and the country's Paediatric Sentinel Surveillance Study group.

The UK public must also be convinced of the safety of the MMR vaccine, says the BMA. "We think it's safe and effective against three very serious concerns," says the spokeswoman.

At a BMA conference on Wednesday, doctors suggested making MMR vaccination compulsory in the UK. In the US, children cannot attend school unless they have had the triple jab.

Crowcroft says: "I really hope the UK vaccination levels don't fall further but I fear they will. Everyone who really understands the subject says MMR is safe. I don't know what else we can say."

Emma Young

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