Incidência de hanseníase nos contatos submetidos ao teste sorológico ML Flow em municípios de Minas Gerais

Abstract

Leprosy is still a public health problem in Brazil. Epidemiological control activities are based on diagnosis, treatment and contact surveillance. Contact surveillance is an extremely important activity for endemy control, but is presently not carried out in a systematic and adequate way. The existing serological tests, including ML Flow, enable patient classification and adequate treatment, as well as identification of contacts with a greater risk of developing leprosy. This test was applied to 2,840 household contacts of new cases detected from October 2002 to March 2004 in Minas Gerais. These contacts were monitored through the Disease Notification Information System (SINAN) during seven to nine years to evaluate the incidence of leprosy related to seropositivity. The incidence of leprosy was higher among the seropositive contacts (3.95%) than among the seronegative ones (2.23%) (p=0.027) (RR=1.72), and higher in those over 15 years of age (3.16%) than in those under 15 (1.25%) (p<0.01). Seropositive contacts who lived in hyper endemic municipalities showed a greater incidence of leprosy (5.35%). This also happened in those who lived in municipalities where the endemy is classified as moderate (4.94%). The incidence of leprosy among seropositives did not show a significant difference by gender, classification of the index case or BCG scar. When analyzing the group that developed leprosy, seropositivity was higher in men, in disability grade 1, in those older than 15, and in those with more than five skin lesions, but the difference was not statistically significant. Seropositivity was greater and significant in those with multibacillary leprosy, in those with borderline leprosy and with two or more nerves involved. The average time from testing to diagnosis was similar in both the seropositive and the seronegative groups. Results showed that 50% of the contacts were diagnosed in less than 10 months, and 90% in less than 20 months, demonstrating the need for monitoring and contact examination in the first year after diagnosis of the index case.