Immunogenicity of Vibrio cholerae O1 fimbriae in animal and human cholera.

Parenteral immunization with either formalin-fixed whole cells of the fimbriate Bgd17 strain or purified fimbriae protected against Vibrio cholerae O1 infection in rabbits, independent of biotype and serotype. Parenteral immunization of adult rabbits with purified fimbriae prior to V. cholerae O1 challenge resulted in a reduction of 2 to 3 orders of magnitude in the number of bacteria recovered from the small intestines of immunized rabbits in comparison to non-immunized controls. IgG and IgA antibodies against fimbrillin of V. cholerae O1 were detected in the convalescent sera of patients with cholera; however, little fimbrial antigen was detected in the commercially available cholera vaccines when examined by polyclonal and monoclonal antibodies against fimbriae. These data suggest that fimbrial hemagglutinin is a major adhesin of V. cholerae O1 and that parenteral immunization with fimbriae generates a specific immune response in the gut that may serve as one means of mitigating subsequent V. cholerae O1 gut infection.

Escherichia coli associated with acute measles and diarrhoea at Kenyatta National Hospital, Kenya.

Three hundred and three children under 5 years old with acute measles and diarrhoea (cases) and 300 other age-matched children with diarrhoea (controls) were examined for enteroadherent E. coli (EAEC) and other agents including rotavirus and Cryptosporidium. EAEC was determined by tissue culture of HEP-2 cells. Other agents were determined by conventional methods. EAEC was identified from both cases and control accounting for 10.3% (31/303) and 15.2% (46/300) respectively. Other bacterial agents were: 10.3% (31/303) from cases and 12.8% (39/300) from controls. A higher detection rate of enteroparasites was found among cases 15% (45/300) than controls 8.9% (27/300) whereas rotavirus was the reverse, 3% (9/303) in cases and 30.3% (92/300) in controls. To our knowledge characterization of EAEC has not been done before and therefore might be attributing factor to some of our unexplained diarrhoeal cases.

Aetiology of diarrhoea in malnourished children at Kenyatta National Hospital.

PIP: 3 groups of children aged 0-5 years were studied at Kenyatta National Hospital between September 1983 and September 1984 to determine the incidence of enteric agents causing diarrhea in infants and children. The 1st group consisted of children with diarrhea alone, the 2nd group had diarrhea and kwashiorkor, and the 3rd had diarrhea and marasmus. Diarrhea occurring alone peaked in the 0-5 month age group; diarrhea and marasmus peaked in the 6-11 month group, and diarrhea and kwashiorkor, the 6-17 month group. Isolation rates of enteric agents (Campylobacter, Shigella, Salmonella, Rotavirus) for the 3 groups were not significantly different; however E. coli was isolated with a higher frequency from children who had diarrhea with marasmus. The most common mixed infection was that of E. coli and Rotavirus, occurring more often in children with marasmus. Most children had a history of diarrhea for 3-5 days duration. Among agents isolated from cases of more than 8 days duration, Campylobacter was most common, and was only isolated from malnourished children. Results indicate that duration of diarrhea before admission was longer in kwashiorkor or marasmic children than children with diarrhea alone. Treatment for diarrhea in all cases should be similar.^ieng