Facts about the filaria:
(1) Adult filaria may persist for years in an infected host.
(2) Microfilaria can survive for weeks in refrigerated blood.
(3) Transfusion-transmitted microfilariasis cannot develop into the adult stage and so the infection is self-limited.
(4) The risk of transfusion-transmitted disease is greatest in endemic areas.
Clinical findings may range from none (asymptomatic) to transient:
(1) fever
(2) lymphadenopathy
(3) splenomegaly
(4) headache
(5) skin rash
(6) eosinophilia
Reactions are more common in patients who have hypersensitivity to filarial antigens. A patient with a serious hypersensitivity to filarial antigens could have a serious allergic reaction.
The risk can be reduced by:
(1) Screening donors for residence or receipt of blood transfusion in endemic areas.
(2) Leukocyte reduction filters at the time of collection may help reduce the number of microfilaria.
(3) Serologic testing of donors.
(4) Deferral of donors with active filariasis.