Tuberculosis and malaria walk side by side in the Brazilian Amazon: an ecological approach.

Objective To assess the spatial distribution of TB and malaria incidence, as well as their spatial association with each other, regardless of environmental and socio-economic factors commonly reported as determinants of both disease rates among the municipalities of Amazonas State, Brazil between 2012 and 2015. Methods Through an ecological approach considering municipalities of Amazonas, Brazil, as unit of analysis, a negative binomial regression model was used to assess association between malaria and TB rates, in which the dependent variable was the average municipal tuberculosis incidence rate. Results Positive associations of overall malaria (beta = 0.100 [CI = 0.032, 0.168], P = 0.004), P. vivax malaria (beta = 0.115 [CI = 0.036, 0.195], P = 0.005), and P. falciparum malaria (beta = 0.389 [CI = -0.0124, 0.791], P = 0.057) with TB rates were found, regardless of the sociodemographic factors included in the study. Conclusion In the Brazilian Amazon, TB and malaria are spatially associated. Therefore, it is very likely that co-infections also occur in this region, regardless of the HIV status.