There was a sporadic outbreak of cholera in 1994 in Okinawa. Immune response of the cholera patients against Vibrio cholerae cell components and extracellular proteins were examined. A potent response to cholera toxin and hemolysin, and generally poor response to purified cellular components were seen. Although the antigen was not defined, marked elevation of vibriocidal antibody and cell agglutination antibody was observed. Only little elevation of the agglutination titer against heat-killed organisms suggests that the antigen (agglutinin) is heat labile protein on the cell surface.
Identification and purification of this protein antigen will elucidate a protective antigen of V. cholerae.

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The neutralization of Cryptosporidium muris sporozoites by rabbit antiserum was examined in vitro and in mice. The sporozoites of C. muris could be separated from intact oocysts by repeated centrifugation. The antiserum reacted strongly with three bands of sporozoite antigens at > 200, 78, and 47.5 kilodaltons during immunoblotting. Heat-inactivated antiserum caused morphological changes seen ultrastructurally in the sporozoites. The antiserum reduced the viability of the sporozoites as measured with fluorescein diacetate. When antiserum-treated sporozoites (1×10⁵) were used to inoculate 7-day-old mice per os, endogenously developed parasites were first detected 10 days later by an indirect fluorescence antibody test. When sporozoites treated with normal rabbit serum were used to inoculate mice, parasites were first detected 6 days later. The results suggest that the antiserum partially neutralizes the infectivity of C. muris sporozoites.

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Seven black fly species were identified, chiefly on the basis of reared adults, pupae and mature larvae collected from Bougainville Inland, Papua New Guinea. All were assigned to the genus Simulium Latreille s. 1. and were further classified into two subgenera, i.e., six species in Simulium (Morops) and one in Simulium (Gomphostilbia). S. (M.) noroense and S. (G.) hiroshii were newly recorded from Bougainville Island, and five other species were described as new species. Under the subgenus Morops, a new species-group was proposed.

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Nine black fly species including five new species were taxonomically studied, chiefly on the basis of reared adults, pupae and mature larvae collected from the Solomon Islands, South Pacific. All species, but one in Simulium (Gomphostilbia), were placed in Simulium (Morops). Within the subgenus Morops four were further classified into the clathrinum-group, one into the papuense-group and three remained ungrouped. S. (M.) papuense was newly recorded from the Solomon Islands. Descriptions of all new species and redescription of S. (M.) sherwoodi were given; mature larvae of S. (M.) sherwoodi and S. (M.) kerei were described for the first time. The pupal pit-like organs of all five known species of the clathrinum-group from Papua New Guinea and Australia were also illustrated.

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