The medical records of hundreds of British servicemen seriously wounded in Iraq and Afghanistan since 2001 have had to be investigated by the Ministry of Defence after the Americans admitted that they may have given some of the injured infected blood transfusions.

The Pentagon revealed at a meeting in Washington in early November that, according to its records, 11 British servicemen had received life-saving blood transfusions from American volunteer donors at US military centres in Iraq and Afghanistan over the six-year period. None of the donors had been pre-screened to detect for any sign of HIV, hepatitis C, syphilis or other blood diseases.

However, MoD officials discovered that the US military medical record-keeping was “so poor”, according to one source, that Des Browne, the Defence Secretary, ordered an immediate search of British records to check whether the Americans had treated other wounded servicemen.

After weeks of trawling through all the records of those who had been wounded and might have received blood transfusions, the MoD discovered that there were seven more who had received on-the-spot blood donations from American military personnel, giving a total of 18. Two of them had left the Armed Forces. Six British civilian security contractors working for the US military in Iraq had also received emergency blood transfusions after being wounded.

The secret investigation of the potential health risks suffered by the 18 military personnel was headed by Britain’s most senior military medic, Lieutenant-General Louis Lillywhite, the Surgeon-General.

The 18 military and six civilians were informed last month, although one of the soldiers was only traced this week after he had returned from a holiday in France. A defence official said ministers had decided against sending the French gendarmerie to his holiday location to tell him the bad news, believing it would be unfair to ruin his holiday.

The Pentagon said the American donors who provided the blood had now tested negative for hepatitis and HIV.

However, there are blood diseases that still have to be eliminated, and none of the 24 Britons involved will know if they are free of contamination for another three weeks. One official said it took three weeks to check for any sign of Chagas disease, a blood infection that can be picked up from insects in South America.

Although British officials could barely suppress their anger and frustration over the delay by the Americans in informing them of the potential medical crisis, it was acknowledged that the fresh blood provided by the volunteer donors almost certainly saved the lives of the 24 Britons.

Professor Stan Urbaniak, a consultant at the Scottish National Blood Transfusion Service in Aberdeen, said that fresh blood,for life-threatening wounds, was the only realistic source to stop massive haemorrhaging and give a chance of survival. “It’s a question of making a judgment between risk and benefit,” he told The Times.

What angered the MoD, however, was that under British procedures, even the emergency blood donors have to be prescreened for contamination.

“When there’s an emergency, donors are called for from a panel of servicemen who have been checked. But the US doesn’t do this, they do the checking after the blood has been donated,” one official said.

A spokesman for the US Embassy in London said that the US blood was “as safe as possible in emergency situations”. Special testing equipment had been sent to all Britons affected.

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