The donor is typically an asymptomatic carrier.
In developed countries where the prevalence of malaria in donors is low, donors are screened during the intake interview. In developing countries testing for malaria is either insensitive or too expensive.
A patient with transfusion-related malaria may present with:
(1) fever
(2) headache
(3) chills
(4) anemia
The patient may present days to months after the transfusion.
The infection can often be identified by examination of the peripheral blood smear although other methods such as PCR can be used.
Risk factors for a serious infection:
(1) delayed diagnosis
(2) vulnerable recipient (immunocompromised, debilitated, etc)
(3) Plasmodium falciparum
If a patient develops malaria and a donor is found to be positive for malaria, then it is important to compare the malaria species, especially in a country where malaria is endemic. If the donor is the source, then the recipient should have the same species.
To reduce the risk of malaria in a transfusion recipient some physicians give a prophylactic course of antimalarials (Nansseu et al) but this depends on selecting an appropriate antimalarial drug.
