Italy's use of a synthetic drug rather than plasma-derived clotting agents for the treatment of mild and moderate haemophiliacs helped to limit the incidence of viral infectivity, the Lindsay tribunal heard yesterday.
Prof Pier Mannuccio Mannucci, who discovered the alternative treatment, known as DDAVP or desmopressin, in 1977, said its use contributed to a "huge difference" in HIV infection rates among severe and mild-to-moderate haemophiliacs.
A 1988 review of Italian haemophilia A patients found that 37 per cent of severe sufferers (who had repeated bleeds) were HIV positive, compared to 14 per cent of moderate and 4 per cent of mild sufferers.
Regarding haemophilia B patients, whose condition made them unsuitable for the receipt of DDAVP, the incidence was higher, with HIV positivity in half of severe, 41 per cent of moderate and 12 per cent of mild sufferers.
The tribunal has heard that DDAVP was in limited use in the Republic.
None the less, some mild-to-moderate haemophiliacs were instead given commercial concentrates, over which there were safety concerns regarding HIV and hepatitis C transmission.
Prof Mannucci, a treating doctor and lecturer at the University of Milan, said the risk of Non-A Non-B hepatitis - as hepatitis C was known - was appreciated by the medical community in around 1978.
With severe haemophiliacs, he said, there was a perception among both doctors and haemophiliacs that the benefits of concentrates, in terms of convenience and effectiveness, "out weighed the risks".
In contrast, because mild and moderate haemophiliacs received only occasional treatment, he said, the risks for them "were seen as unacceptable".
He developed DDAVP, which stimulated the release of factor 8 in patients, as an alternative treatment in 1977.
It was recommended to treating doctors in Italy the following year and was "widely used" in the country.
In other countries, however, he said he did not think it was used on a large basis before the 1980s. He said some reluctance to its use was probably caused by a report from a Scottish doctor who said a patient developed signs of water intoxication, probably as a result of excessive use of the drug.
Regarding his choice of treatment for children from 1980 onwards, he said in some instances he probably used cryoprecipitate, which was seen as safer than concentrate as it was sourced from a smaller pool of donors. But, he said, the temptation was to use "the little miraculous bottle" of concentrate.
He said cryo was considered "obsolete" in the 1970s by the majority of the medical community "and, I take the liberty, of the patients".
Patients were informed of the risks of both hepatitis and HIV and "none" of them considered the possibility of stopping their use of concentrates, he said.
Prof Mannucci conceded, however, that the medical profession was "very uneasy and very unhappy" with the manner in which it responded to the threat of HIV. While he said he had not much regret about hepatitis, with HIV "one does wonder why we did not understand [the risks] earlier".
He continues his evidence today.
