Community-based studies of diarrhea etiology and epidemiology were carried out from July 1982-June 1984 in 153 infants residing in a poor peri-urban community near Lima, Peru. Study infants had nearly 10 episodes of diarrhea in their first year of life. Diarrhea episodes were associated with organisms such as Campylobacter jejuni, enterotoxigenic and enteropathogenic Escherichia coli, Shigella, rotavirus, and Cryptosporidium. These organisms appeared to be transmitted to infants in the home through animal feces, through contaminated water and food, and by direct person-to-person contact. A particularly important route of transmission may have been weaning foods, which were often contaminated because of improper preparation and inadequate cleaning of utensils. Improved feeding practices, along with avoidance of animal feces and improved personal and domestic hygiene, should be considered important interventions in reducing the high incidence of diarrhea in infants in developing countries.

The 1991 Peruvian cholera epidemic has thus far been responsible for 600,000 cholera cases in Peru. In an attempt to design a cholera surveillance program in the capital city of Lima, weekly sewage samples were collected between August 1993 and May 1996 and examined for the presence of Vibrio cholerae O1 bacteria and V. cholerae O1 bacteriophages (i.e., vibriophages). During the 144 weeks of surveillance, 6,323 cases of clinically defined cholera were recorded in Lima. We arbitrarily defined an outbreak as five or more reported cases of cholera in a week. The odds of having an outbreak were 7.6 times greater when V. cholerae O1 was present in sewage water during the four previous weeks compared with when it was not (P < 0.001). Furthermore, the odds of having an outbreak increased as the number of V. cholerae O1 isolations during the previous 4 weeks increased (P < 0.001). The odds of having an outbreak were 2.4 times greater when vibriophages were present in sewage water during the four previous weeks compared with when they were not, but this increase was not statistically significant (P ‫؍‬ 0.15). The odds of having an outbreak increased as the number of vibriophage isolations during the previous 4 weeks increased (P < 0.05). The signaling of a potential cholera outbreak 1 month in advance may be a valuable tool for the implementation of preventive measures. In Peru, active surveillance for V. cholerae O1 and possibly vibriophages in sewage water appears to be a feasible and effective means of predicting an outbreak of cholera.

Cultures were made from blood, bone marrow, stool and duodenal contents (obtained with string capsules) from 36 patients with bacteriologically proven typhoid fever on admission to hospital. Duodenal content cultures proved to be as sensitive in diagnosis (86%) as bone marrow (75%) and more effective than blood (42%) and stool (26%) cultures in recovery of Salmonella typhi. The sensitivity of duodenal content cultures was not modified by the duration of illness at admission or by previous antibacterial therapy. Even on the seventh day of effective treatment with chloramphenicol, the culture of duodenal contents remained positive in 8 of 17 patients, whereas salmonellae were isolated from stool cultures in only 2 of the same patients. The results obtained with the string capsule, together with the simplicity, economy and acceptability of the procedure, the fact that it can be performed with minimal facilities and the advantages of bacteriological recovery for antibiotic sensitivity testing, suggest that its adoption would be very helpful in efforts to control this disease.

Our study indicates that from the beginning of this epidemic, V. cholerae O1 caused diarrhea in children as well as adults and should therefore be considered as one of the possible pathogens when children from a cholera-affected area develop diarrhea.