WHO Position Paper on Cholera Vaccines

In the most recent epidemic of cholera in Latin America, nearly a million cases were reported and almost 9000 people died between January 1991 and December 1993. The epidemic spread rapidly from country to country, affecting in three years all the countries of Latin America except Uruguay and the Caribbean. Case-control studies carried out in Peru showed a significant association between drinking water and risk of disease. Cholera was associated with the consumption of unwashed fruit and vegetables, with eating food from street vendors and with contaminated crabmeat transported in travellers' luggage. This article documents the spread of the epidemic and its routes of transmission and discusses whether the introduction of the epidemic to Peru and its subsequent spread throughout the continent could have been prevented. PIP: Latin America's first cholera epidemic this century struck along the Peruvian coast in January 1991. Rapid and intense surveillance could not stop it from crossing Peru's borders. Public health interventions did keep the case fatality rate low (0.92%), however. Cholera first spread to Ecuador, then Colombia. By the end of 1993, all countries of Latin America except Uruguay and the Caribbean reported cholera cases. The greatest proportion of cholera cases and the highest incidence rate were in Peru (63.7% and 26.9/1000, respectively). Most cholera cases were reported in 1991 and were concentrated in Peru (82.3%). 45.5% of all cholera deaths occurred in 1991. Central America had the highest case fatality rates. The routes of transmission of Vibrio cholerae in this Latin America cholera epidemic included unwashed fruit and vegetables, contaminated food and ice from street vendors, contaminated drinking water, and contaminated crab meat transported in luggage. The source of the epidemic in Peru has not been identified. Peru had in place an extensive oral rehydration therapy program, an epidemic field investigation service, and laboratory resources. Most Latin American countries, particularly in rural areas and the outskirts of big cities, lack water supply and basic sanitation. Untreated waste water is discharged into rivers and the ocean. Inadequate sanitation facilities and the use of inadequately treated water are likely responsible for the spread of the cholera epidemic in Latin America.