Isolation of semliki forest virus from Aedes (Aedimorphus) argenteopunctatus (theobald) collected in Portuguese East Africa

1. 1) A virus was isolated in mice from Aedes (Aedimorphus) argenteopunctatus (Theo.) collected at Namacurra, a town near the coast in Portuguese East Africa. 2. 2) Immunological studies with the haemagglutination-inhibition, complement-fixation and neutralization tests showed this virus, within the limits of the tests, to be immunologically identical with Semliki Forest virus. 3. 3) The previously demonstrated close immunological relationship among Semliki Forest, Mayaro and chikungunya viruses was confirmed. 4. 4) Results are presented of neutralization and haemagglutination-inhibition tests with three Group A viruses against selected sera from residents of northern Natal, Union of South Africa and Portuguese East Africa.