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[Transfusion-induced malaria: risks, prevention and cost (1 year's experience)]
Abstract:
Three cases of transfusion induced paludism have been seen in Rouen since 1976. Two of them were due to Plasmodium falciparum and the third to Plasmodium malariae. In order to improve the prevention of this disease, a survey was carried out in 1980 which concerned 51,000 blood samples, 1,020 blood donors were selected because they had lived in a malarial endemic zone. Among them, 92 subjects were detected by an indirect immunofluorescence reaction as having a titer exceeding 1: 20 and their blood was kept aside any transfusional use. These results were studied according to the geographical area concerned, the ethnical origin, the time elapsed since the return and whether or not a chemoprophylaxis had been used. The present study gives further evidence of the risk linked to a stay in Africa. But neither the time since the return, nor the use or not of a chemoprophylaxis seemed to influence the serological results. The five years exclusion rule, used up until now, came to be at the same time too much and insufficiently limitative, since it would have eliminated 1.4% blood donors while the serological controls would eliminate only 0.18%. On the other hand, 14 blood donors, who were back in France for more than 5 years and presented with a positive serology, would have been considered as normal. In the light of these results, a practical line is given based on the association of a simple inquiry to a malarial serology.
Insights
Transfusion-induced malaria, or paludism, is a risk for blood recipients. A survey found that indirect immunofluorescence testing is more effective than the current 5-year exclusion rule for identifying infected blood donors.
Area of Science:
- Medical Parasitology
- Transfusion Medicine
- Epidemiology
Background:
- Transfusion-induced malaria (paludism) poses a risk, with cases documented in Rouen.
- Previous prevention strategies relied on donor history, such as time elapsed since return from endemic areas.
Purpose of the Study:
- To evaluate the effectiveness of serological screening for identifying blood donors at risk of transmitting malaria.
- To compare serological screening with the existing 5-year exclusion rule for blood donors returning from malarial zones.
Main Methods:
- A survey of 51,000 blood samples identified 1,020 donors with a history of living in malarial endemic zones.
- Indirect immunofluorescence testing was used to detect antibodies against malaria parasites in selected donors.
- Results were analyzed based on geographical origin, ethnicity, time since return, and chemoprophylaxis use.
Main Results:
- 92 out of 1,020 screened donors (approximately 9%) had a positive indirect immunofluorescence titer (> 1:20) and their blood was excluded.
- The 5-year exclusion rule would have incorrectly excluded 1.4% of donors, while serological screening identified only 0.18% of donors requiring exclusion.
- Fourteen donors returning from endemic areas for over 5 years had positive serology, highlighting limitations of the current exclusion period.
Conclusions:
- Serological screening, specifically indirect immunofluorescence, is a more accurate method for identifying blood donors potentially carrying malaria parasites.
- The current 5-year exclusion rule is both overly restrictive and insufficiently protective.
- A combined approach of donor inquiry and malarial serology is recommended for improved prevention of transfusion-induced malaria.