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 unitof 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 (b=0.100 [CI=0.032, 0.168],P=0.004),P. vivax malaria (b=0.115 [CI=0.036, 0.195], P=0.005), and P. falciparum malaria (b=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 verylikely that co-infections also occur in this region, regardless of the HIV status.