Risk of malaria transmission through blood transfusion and its detection by serological method

ABSTRACT

To assess the risk of transmission of malaria through blood transfusion, and compare efficacy of testing by immunochromatographic[ICT] devices vis a vis peripheral blood film [PBF]. Design: 300 blood samples were tested divided into three equal groups of healthy volunteers, voluntary non-remunerated blood donors and patients suffering from malaria. Testing was carried out by a serological screening method, together with observation of peripheral blood films. Setting: Samples were collected from different sites and tested at the Institute of Haematology and Blood Transfusion Service, Punjab. Subjects: One hundred blood donors were selected from persons donating blood at the Institute or on mobile sessions. An equal number of healthy controls were students and staff of different colleges and the Institute. Samples of 100 patients of pyrexia and diagnosed clinically as suffering from malaria were collected from multiple clinics, laboratories and hospitals in Lahore. Main outcome measures: Assessment of the risk of transmission of malaria through blood and blood products and the comparison of serological testing for malaria with conventional peripheral blood film detection. Amongst healthy blood donors we did not find even a single case of malaria and there was no report of persistent post transfusion pyrexia. We are unable to comment on species frequency in blood donors. However, amongst known patients of malaria we found a higher frequency of Plasmodium vivax[P.v] as compared to Plasmodium falciparum[P.f]. Testing by serological method, helped us to diagnose 5% of our patients who were missed by peripheral blood films. Between properly selected voluntary non-remunerated blood donors the incidence of malaria transmission is zero and the blood is safe for transfusion. Serological testing shows good correlation with peripheral blood film detection. In fact, it can detect the disease even when film detection has been unsuccessful. If proper donor selection criteria are observed there is little risk of transmitting malaria through transfusion. However, as the donor pool in the Service is not necessarily totally that of voluntary non-remunerated donors and substantive numbers of replacement/first time, occasionally uneducated/unaware donors, are being bled, screening for malaria will not be totally unrewarding