RESUMEN
In the first 3 weeks after the 1976 earthquake in Guatemala a system for collecting, analysing, and disseminating information of medical importance was instituted in the disaster area. Data on cases of selected diseases, number of available hospital beds, and medical supplies were collected, and reported epidemics were investigated. The system functioned well despite the limited numbers of trained personnel. Collection and analysis were quick enough for data to be used immediately in decision-making. No epidemics of communicable diseases were observed in the affected area. The number of dog bites in Guatemala City increased but no cases of rabies were reported. The success of the surveillance system in Guatemala suggests that immediate use of epidemiological methods should be an integral part of disaster relief.