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HTLV-I screening in Britain

The human T cell leukaemia/lymphoma virus type I (HTLV-I) was isolated nearly 17 years ago from a patient who had what is now called adult T cell leukaemia/lymphoma. This aggressive condition responds poorly to chemotherapy, with a median survival of only a few months.1 HTLV-I is also unequivocally linked with tropical spastic paraparesis, a progressive, unremitting myelopathy for which there is no specific treatment. HTLV-I is transmitted through sexual intercourse (especially from men to women), breast feeding, sharing intravenous needles, and blood transfusion. Between 12.8% and 63.4% of people receiving blood infected with HTLV-I will seroconvert.2 3 Fresh blood products (those less than six days old) have a transmission efficiency of 80%.2

Transfusion services in Britain do not currently screen blood donors for HTLV-I. This policy is based on a low prevalence of HTLV-I among British blood donors (ranging from 1 in 19000 donors in North London to 1 in 80000 in Yorkshire), a low risk of developing the disease after infection, and a high incidence of false positive results on serological tests for HTLV-I.4 5 But new evidence should prompt a reappraisal of the policy.

HTLV-I is endemic in south west Japan, the Caribbean basin, Africa, the southern United States, and parts of South America. The virus has generally been considered to …