The government was last night struggling to avert a major public health emergency over dwindling public confidence in the safety of the MMR vaccine, despite Tony Blair's insistence that expert scientific opinion overwhelmingly backs the controversial triple jab.
Faced with the lethal mix of tabloid uproar, mounting parental anxiety, and Conservative attempts to exploit ministers' discomfort, Mr Blair denounced MMR critics for "scaremongering" and warned parents that refusal to have the vaccine could prove far more threatening to their children.
The stakes were raised when eight new measles cases were confirmed in south London. A Lambeth, Southwark and Lewisham health authority official, said the total number of confirmed measles cases in the capital was now11.
The area, in which take-up of the MMR vaccine has slumped to 65% against a target of 95%, has another 18 suspected cases.
Four measles cases have been reported in Gateshead, south Tyneside, with three more suspected cases in nearby Teesside revealed yesterday.
The North Tees children are of pre-school and primary school age and are not thought to be part of a cluster, said Ian Holtby, consultant in communicable disease control at Tees health authority. Swabs have been taken for testing, which could take a week or two.
While Gateshead has a high immunisation rate of 91%, Teesside is on 81%, just below the national average of 84.2%.
"Not enough children are being immunised to protect against a major outbreak," said Dr Holtby. "There is a risk of a large increase in cases of measles and this is what we would like to avoid. We would urge any parent to get their child vaccinated."
The handful of cases in Tyneside and Teesside may prove not to be out of line with previous years. The Public Health Laboratory Service expects around 100 cases a year, but when immunisation levels are high, the virus does not spread.
Streatham, in south London, appears to have experienced an outbreak of the sort predicted by health officials ever since MMR immunisation levels started to drop in 1998.
Yesterday, three influential medical bodies aired their concern by issuing a joint statement backing the safety of the triple vaccine. The Faculty of Public Health Medicine, the Royal College of Paediatrics & Child Health and the Community Practitioners and Health Visitors Association said they had been carefully monitoring the data and saw no reason to change their advice to parents.
"Some parents are requesting single vaccines, which are unproven in both safety and effectiveness," they said. "In contrast the MMR is now probably the best-researched vaccine worldwide and its few very rare side-effects are well known.
"In contrast there has been little research conducted to ascertain whether single vaccines for measles, mumps and rubella could have significant side-effects. We do not believe that it is sensible to subject children to six injections without good reason - whilst prolonging the risk of exposure in the interim to those diseases which they are still waiting to be vaccinated against."
After a day when Downing St officials categorically denied claims in the Sun that the PM had ordered a review of the cost of the single vaccine alternatives, Mr Blair battled to win the argument with facts before flying off to west Africa.
Urging parents to consult their doctors or their websites for "the full evidence", Mr Blair told MPs at question time: "The scaremongering - and it is scaremongering - about this vaccine is wrong. Often such scaremongering doesn't matter. In this case it does."
The Sun's political editor, Trevor Kavanagh, toured the radio and TV studios to reinforce its story, although it was denied by No 10 before the story ran yesterday.
Mr Blair's refusal to say whether his son Leo has had the MMR jab has inflamed the tabloids - even though the vast weight of medical evidence around the world endorses MMR as the safest option.
Mr Blair said that when single jabs replaced MMR in Japan in 1994-99 there were 85 resultant infant deaths - and none in the same period in Britain. When the mid-70s whooping cough jab row pushed down parental take-up in the UK, 100 children died.
Around 90 countries use the MMR vaccine, and some 500m doses have been administered since 1972, Mr Blair and his aides insisted. "If anybody has any doubts the full evidence is available and can be given to any parent who wants it," Mr Blair told MPs.
