The health of children is at risk because an NHS computer system wrecked 20 years of accurate immunisation records.

Faulty software introduced in 2005 has left some primary care trusts (PCTs) unable to track whether children have been vaccinated and screened for genetic conditions, raising fears that many are unprotected against diseases. Parents are not being reminded when their children are due for jabs and check-ups.

The Health Protection Agency cannot publish full statistics on the uptake of vaccines because the five worst-affected London trusts cannot provide accurate data.

When the shortcomings of the Child Health Interim Application (CHIA) software were disclosed by The Times a year ago, the Department of Health stated that the problems were being addressed. Staff were said yesterday to be “in despair” at continuing difficulties with the system supplied by BT.

Christine Sloczynska, consultant community paediatri-cian at Waltham Forest PCT, in East London, said: “I’m sure there will be kids who slip through the net and will be unimmunised. Our immunisation take-up has fallen from 94 per cent to 58 per cent, but we don’t know how much it is due to children missing their vaccinations, or to lack of data.”

The Health Protection Agency said that five trusts had been excluded from national figures for uptake of MMR and other vaccinations as their data were considered unreliable. Pat Troop, head of the agency, said: “There is still a gap in the data, and it’s something the local NHS are concerned about, not just us. Not monitoring coverage of measles is how infections might happen.”

Mike Catchpole, of the agency, said that it was not possible to predict when the affected PCTs could provide the data.

The CHIA software was introduced in ten London trusts when an older system was withdrawn. Dr Slocynzska said that the system could not be used to generate lists of those who match particular criteria, such as missing vaccinations. This makes it difficult for GPs to issue reminders.

Parents are still issued with a “red book” listing a vaccination schedule, but the problems with the computer make it hard to tell them when new jabs are available. Birth records formerly sent online from maternity units must be entered by hand, and there is a backlog. “We are sometimes told of a child’s death before we know it has been born,” Dr Sloczynska said.

BT has promised to replace the software.

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