PREVENTION OF SPOROGONY OF PLASMODIUM-FALCIPARUM AND P-BERGHEI IN ANOPHELES-STEPHENSI MOSQUITOS BY TRANSMISSION-BLOCKING ANTIMALARIALS

The sporontocidal activity of three 8-aminoquinolines, a 1,4-naphthoqu inone, and three dihydroacridine-diones was determined against the ANK A clone of Plasmodium berghei and both chloroquine-sensitive (NF54) an d chloroquine-resistant (7G8) P. falciparum. Anopheles stephensi mosqu itoes previously fed on P. berghei-infected mice or P. falciparum-infe cted cultures were refed on uninfected mice treated previously with a given drug. Sporontocidal activity was determined by assessing both oo cyst and sporozoite development. Neither primaquine nor menoctone exhi bited sporontocidal activity against P. berghei or either strain of P. falciparum at a dose of 100 mg base drug/kg mouse body weight, wherea s the other five compounds each effectively interrupted the sporogonic development of all three parasite strains at this dose. These data cl early demonstrate that experimental dihydroacridine-diones and 8-amino quinolines are capable of interrupting the sporogonic development of P . berghei and chloroquine-sensitive and chloroquine-resistant P. falci parum. These data also suggest that the P. berghei model may be used t o accurately predict sporontocidal activity against P. falciparum.