RESUMO
The emergence of old and new communicable diseases is becoming an importanty public health problem in industrialized and developing countries worldwide. Chile experienced at the end of the seventies and during the eighties, epidemics of several emergent communicable infectious diseases whose relevance as public health problems had steadily decreased in the previous 25 years. The most strinking of these epidemics was a severe outbreak of typhoid fever that lasted at least 10 years. The majority of the cases ocurred in the urban setting of Santiago. Several investigators suggested, in light of apparently good sanitation statistics, that factors responsible for this outbreak of typhoid were an increase in the number of chronic carriers of salmonella typhi, the lack of microbiological food controls and the consumption of vegetables irrigated with waste water contaminated with S typhi. However, there is a dearth of epidemiological information and field work confirming the role of these factors in this typhoid outbreak. Moreover, the sudden, massive and urban characteristics of this epidemic, coupled to contemporary information regarding shortcoming on the preparation of drinking water and on decreased availability of drinking water to the population in Santiago regardless of good sanitation statistics, suggest that this outbreak may have been partially waterborne. The beginning of this typhoid outbreak also coincided with increased rain fall, with rapidly deteriorating economic and social conditions manifested in high rates of unemployment, and with decreased government investment on social services, including sanitation and health. Al these factors are known to influence the epidemiology of typhoid and other emergent diseases worldwide