Leprosy elimination phase in Alagoas, 2001-2022: an ecological study

To analyze the epidemiological scenario and leprosy elimination phase in the municipalities of Alagoas state, Brazil, from 2001 to 2022.

This is an ecological study using surveillance data from the Notifiable Health Conditions Information System; detection and prevalence rates of the disease, along with absolute and relative frequencies, were used; temporal trends were evaluated using joinpoint regression, spatial autocorrelation was assessed with Moran's index, and municipalities were classified according to the Leprosy Elimination Monitoring Tool (LEMT) proposed by the World Health Organization.

Between 2010 and 2022, there was a significant annual decrease of -2.89% (95% confidence interval [95%CI] -5.65; -0.91) in the prevalence rate, -4.43% (95%CI -6.56; -2.20) in the detection rate in the general population and -6.03% (95%CI -10.00; -1.46) in the detection rate in the population under 15 years of age; significant high-high clusters (p-value <0.050) were observed in the municipalities of Jacaré dos Homens, Pão de Açúcar and Carneiros; according to the LEMT in 2022: 7 (6.8%) municipalities were in phase 1 - up to interruption of transmission, 41 (40.2%) in phase 2 - up to disease elimination, 27 (26.5%) in phase 3 - post-elimination surveillance and 27 (26.5%) in phase 4 - non-endemic status.

The data pointed to trends of reduction in the leprosy burden in the state, although some municipalities continue to show high rates; the use of LEMT with secondary data should be approached cautiously, as the absence of reported cases does not imply disease elimination in scenarios of underreporting and underdiagnosis.