RESUMEN
In a one-year prospective study carried out to define the role of rotavirus and Escherichia coli in local childhood diarrhea, we determined the prevalence of both agents in 54 diarrheic children attending a health center in Botucatu. Diarrheogenic E. coli (DEC) strains were characterized by O:H serotyping, a search for virulence genetic markers, and assays of adherence to HEp-2 cells. Except for enteroaggregative E. coli (EAEC), no other DEC category was detected in the children's stools. Both EAEC and rotavirus were isolated from 22 of the 54 (41.0 percent) diarrheic children as single agents or in combination with other enteropathogens. However, when considering the presence of a single agent, EAEC was dominant and isolated from 20.4 percent of the patients, whereas rotavirus was detected in 14.8 percent. These results indicate that rotavirus and EAEC play a significant role as agents of childhood diarrhea in the local population
Asunto(s)
Humanos , Lactante , Preescolar , Niño , Adolescente , Diarrea , Escherichia coli , Infecciones por Escherichia coli , Rotavirus , Adhesión Bacteriana , Brasil , Diarrea , Escherichia coli , Infecciones por Escherichia coli , Heces , Reacción en Cadena de la Polimerasa , Prevalencia , Estudios Prospectivos , Estaciones del AñoRESUMEN
Zeta plus filter membranes (ZP60S) have been shown to be efficient for rotavirus concentration from wastewater and for the reduction of cytotoxicity for cell cultures. Recently a variability in both properties was observed. In view of the low costs and the high virus recovery rates obtained in the past, we re-evaluated the application of ZP60S filter membranes for virus concentration from environmental samples. Some factors that could interfere with the concentration strategy using ZP60S were also considered and assessed including the type of water to be filtered and the possible release of toxic substances from the membrane matrix during filtration.
Asunto(s)
Membranas Artificiales , Rotavirus/aislamiento & purificación , Aguas del Alcantarillado/virología , Microbiología del Agua , Técnicas de Cultivo de Célula , Citotoxinas , Filtración/métodos , Aguas del Alcantarillado/químicaRESUMEN
Simian rotavirus SA-11, experimentally seede, was recovered from raw domestic sewage by a two-step concentration procedure, using filtration through a positively charged microporous filter (Zeta Plus 60 S) followed by ultracentrifugation, effecting an 8000-fold concentration. By this method, a mean recovery of 81 per centñ7.5 of the SA-11 virus was achieved.