Abstract
Objective: To describe the outbreak of cholera that occurred in Ecuador in 1998 during the El Niño weather phenomenon, to present data on the resistance of the circulating strains of Vibrio cholerae to antimicrobial drugs, and to describe the preventive measures taken by health authorities in order to reduce the impact of the disease.Methods: The epidemiological data came from three sources: 1) the registry of the National Bureau of Epidemiology of the Ministry of Public Health of Ecuador, 2) the registry of the National Institute of Hygiene and Tropical Medicine, and 3) the final report of the Training Program for the Fight against Cholera and Diarrheal Diseases. Isolation, identification, and serotyping was done of V. cholerae in the feces samples from 10% of the suspected cholera cases that were identified between 1 January and 31 December 1998. The suspected cases were defined by the sudden appearance of watery diarrhea, with or without dehydration, in epidemic areas. The strains that were isolated were submitted to a standard antibiogram by the diffusion method, in which the following antibiotics were tested: amoxicillin, tetracycline, trimethoprimsulfamethoxazole, vibriostatic compound O/129, nalidixic acid, erythromycin, norfloxacin, ciprofloxacin, gentamycin, chloramphenicol, and colistin.Results: In 1998 there were 3 755 cases reported in 17 of the 21 provinces of the country. This corresponds to an incidence rate of 53.96 per 100 000 population. Thirtyseven patients died, for a case fatality rate of 0.97%. A total of 301 strains of V. cholerae were isolated in the 637 suspected-cholera samples that were processed; all corresponded to V. cholerae O1, El Tor, subtype Ogawa. All of the strains were sensitive to tetracycline and to quinolones; 5.6% of the strains were resistant to erythromycin. The only strain resistant to amoxicillin was multiresistant. Officials in Ecuador implemented a series of preventive measures, and the surveillance system was strengthened in order to reduce the impact of the disease.Conclusions: The preventive measures helped to reduce the impact of the 1998 cholera epidemic in Ecuador, in terms of both incidence and the case fatality rate. Given the overall sensitivity of the strains to the antimicrobial drugs, there is no reason to change the current treatment regimens in the country. Taking into account the frequency of natural disasters in Ecuador and the relation that they have to the reappearance of cholera, interventions should be designed that make it possible to prevent and control the reappearance of the disease and its spread to the most vulnerable provinces of the central Sierra mountainous region and the eastern part of the country.