The risk of acquiring a transfusion-induced infection in Zambia was studied for the first time. Blood slide examination of donors, despite the insensitivity of the method, established malaria as the most serious hazard. The species involved was Plasmodium falciparum, the cause of cerebral malaria, and which could be rapidly fatal in a non-immune host visiting an endemic area. Microfilariae of Dipetalonema perstans and Wuchereria bancrofti were also found in donor populations. While no disease may be induced, allergic reactions due to the breakdown products of dead microfilariae may manifest themselves. Several cases of transfusion-induced malaria, a case of relapsing fever and a case of rhodesian trypanosomiasis are reported. Toxoplasmosis and kalatazar, which may also be transfusion-induced, are both known to occur in the country but no cases were observed. It is emphasized that prophylactic measures should be mandatory in areas where no regular, screened, donor panel is available. The awareness and ackowledgement of the risk of transfusion-induced infections may be the best safeguard against the serious consequences in developing countries.