Maintenance of Glossina morsitans morsitans on antiserum to procyclic trypanosomes reduces infection rates with homologous and heterologous Trypanosoma congolense stocks.

Three experimental groups of male Glossina morsitans morsitans were infected at their first feed with procyclic forms of different stocks of Trypanosoma congolense and subsequently maintained on a diet containing rabbit antiserum to one of these stocks. Control flies were similarly infected but were then maintained on normal rabbit serum. Dissection of the flies 19-21 days post infection showed a reduction in both immature and mature infection rates in all groups fed on antiserum by comparison with control flies. These results suggest that vaccination with a single procyclic T. congolense strain could reduce transmission of both homologous and heterologous T. congolense strains which might, in certain epidemiological circumstances, provide an alternative or additional control method for African trypanosomiases.