Bancroftian filariasis in a Philippine village: clinical, parasitological, immunological, and social aspects.

The distribution and effects of Bancroftian filariasis in 535 inhabitants of a Philippine village were investigated. Clinical, parasitiological, immunological, and socioeconomic assessments were made. A history of acute lymphatic inflammation and the presence of inguinal lymphadenopathy were common. Lymphatic obstructive disease, defined as leg edema, hydrocele, or an epididymal cyst, was more common in men than women and increased progressively with age. The prevalence and intensity of microfilaremia rose with age in males, whereas the prevalence but not the intensity of infection increased with age in females. The prevalence of immunological responsiveness, as assessed by skin reactivity to microfilarial antigen and serum antibodies to adult filarial worms, increased with age in both males and females. There was no relationship between either microfilaremia or obstructive disease and the ability to work or have children, but both were more common in heads of households with the lowest socioeconomic scores. Epidemiological factors which may have contributed to these findings are discussed. (author's modified)