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Lymphatic filariasis is caused by the nematodes Brugia malayi, Brugia timori, and Wuchereria bancrofti. The disease occurs in developing countries and is more frequent in urban areas. An estimated 4 billion people live in at-risk areas. In Brazil the endemic is caused by W. bancrofti and was first documented in 1878. It was first detected in Recife in 1952. Currently, Recife and Belém are the only cities in Brazil where the endemic is considered a public health problem. The objectives of this study are to discuss the epidemiology and control of lymphatic filariasis and review its control since it was reported by Rachou in 1952. We analyze the "campanhista" or campaign-oriented model employed by the Sucam/FNS institutional program, as well as several proposed innovative methods. We present available strategies for control of filariasis through primary health care services, decentralization to the local level (or "municipalization"), and community-based health programs.

A pilot study for the control of Bancroftian filariasis transmission was developed in two areas of Recife, Brazil, where microfilaraemic prevalence was 10% in 1991. Mass treatment with diethylcarbamazine (DEC) using low and spaced doses was employed in both areas. In one such instance, DEC therapy was associated with vector control using physical measures and periodic treatment of Culex breeding sites with the entomopathogen Bacillus sphaericus. The vector population density, reaching 60 - 120 Culex/room /night before the intervention, was drastically reduced to 4 - 16 Culex/room/night, and maintained at this level for more than two years. Actions to engage the local school community in the vector control process were implemented, and as a consequence several classroom and extracurricular activities were put into practice, culminating with the effective participation of a team of students called the "Vector Vigilantes", in the application of control measures against the vector. The enthusiastic involvement of schoolteachers and students pointed to schools as a place amenable to programs such as this.

Two districts in Recife (Santo Amaro and Campo Grande) and two districts in Olinda (Sapucaia and Salgadinho), were selected for a comparative study of bancroftian filariasis in Greater Recife. Selection parameters included similar socio-economic, demographic, and endemic levels of lymphatic filariasis. In the districts studied, streets were chosen randomly. These clusters consisted of 110 people each. A population sample was stratified by sex and age: 0-4, 5-9, 10-14, 15-19, 20-29, 30-39, 40-49, 50-59 and 60 years old and over. The parasitological data were obtained by measuring thick blood smears (60 micro l), collected from 8:00 to 12:00 PM and processed and stained with hematoxylin. The data were described in tables, and logarithimic expression graphics were used to analyze parasitic densities. In general, Recife showed a prevalence of 13.5%, and Olinda 12.3%. Mean parasitic densities were 41 and 70 microfilariae/60 micro l (mf/60 micro l), respectively. Higher microfilaremic rates were observed in Recife for the 20-29-year age bracket and in Olinda in the 30-39-year bracket. The authors concluded that the disease has returned to former endemic levels, and the data described call for a reevaluation of control campaigns carried out by the Brazilian National Health Foundation, since the endemic has already reached serious proportions.