SUMMARYIn May 1980 an extensive outbreak ofgastroenteritis occurred in a private school in the city of Rio de Janeiro. Examination of faeces and paired sera showed that this outbreak was caused by both rotavirus and a virulent strain of Shigella sonnei.In the first 19 stool samples collected seven (37 %) had rotavirus only, six (32 %) had Sh. sonnei only, while four (21 %) had both agents. Examination of the second and third stool collections revealed only the presence of Sh. sonnei. The 18 paired sera showed seroconversion for rotavirus in four cases (22 %) and in seven cases (39 %) for Sh. sonnei. The overall attack rate ofthe disease was approximately 75 %, the nursery and kindergarten having higher attack rates. Students in all grades became sick at the same time, and the unimodal curve of the onset dates of symptoms indicates a common source outbreak. Evidence suggested a contaminated water supply.

No abstract

Twenty-four monoclonal antibodies (mAbs) against group B Neisseria meningitidis surface antigens were analyzed by immunoenzymatic assays and by a bactericidal test. Two mAbs were specific to polysaccharide B and one to lipopolysaccharide. The others were specific to polysaccharide B and one to lipopolysaccharide. The others were directed against outer membrane proteins ranging in molecular mass from 25 to 200 kDa. The outer membrane protein epitopes recognized by the mAbs were not conformational and were located on the outer surface of the microorganism. Linear epitopes on the class 5 protein, exposed on the surface of the membrane, were able to induce bactericidal antibodies to the homologous strain. The susceptibility of Neisseria meningitidis to these antibodies was unchanged when this organism was cultivated under conditions of iron depletion. These results demonstrate that peptides derived from class 5 proteins are potentially important in synthetic peptide or in recombinant protein vaccines containing linear bactericidal epitopes.

The circulation flow and maintenance of enteropathogenic bacteria were studied from May 1982 to April 1983 in a population of institutionalized children and adult staff contacts in the city of Rio de Janeiro, Brazil. Subjects were assigned to three groups: A and B, included, respectively, 105 and 46 children with diarrhea who were admitted in the institution in different periods, and group C with 82 adult contacts. Faecal cultures were positive in 35.2%, 39.1% and 19.7% of subjects of groups A, B, and C, respectively. It suggests that the transmission was probably fostered by the environment because of as high as 30% of faecal contamination was found in environmental samples. Higher rate of isolation and elevated antibodies levels pointed out that Escherichia coli (EPEC) was the prevalent agent. Shigella predominated in the serological tests. These findings suggest that the institution itself may play an important role in the epidemiology and transmission of enteric infections in the community.