| Congresso Brasileiro de Microbiologia 2023 | Resumo: 321-2 | ||||
Resumo:Leprosy is an infectious disease caused by the bacterial pathogens Mycobacterium leprae (M. leprae) and Mycobacterium lepromatosis (M. lepromatosis). It occurs mainly in tropical and subtropical countries and is considered a neglected tropical disease. In addition to humans, animals such as nine-banded armadillos and red squirrels are species naturally infected. The transmission mechanisms between animals and humans are not well established; however, the probable route is aerosol transmission. As for M. lepromatosis, the global extent of infection and its effect on the development of leprosy are still unknown. The objective of this study was to investigate the presence of M. leprae and M. lepromatosis in non-volant small mammals of the order Didelphimorphia and Rodentia through polymerase chain reaction (PCR) assay. During 2015 and 2018, field expeditions were carried out in three municipalities, covering biotic elements of the Amazon and Cerrado biomes, in the Mato Grosso State, Midwest of Brazil. A specific primer for repetitive sequences of the genomic DNA of M. leprae and M. lepromatosis targeting the RLEP and RLPM gene, respectively, was used to screen for these agents in samples spleen. The molecular detection of M. leprae DNA in the samples was 13.8%. The multi-level model for the presence of M. leprae showed that Cerrado biome (OR: 53.5, p < 0.001) revealed a strong association. M. lepromatosis was not detected. The state of Mato Grosso is a historic leprosy endemic area with hyperendemic levels (>40/100,000 inhabitants) in most municipalities. M. leprae infections in small non-volant mammals in the Amazon biome ranged from 1.5-1.7%. In the Cerrado biome (savanna), M. leprae infection ranged from 42.3-50.0%. The Cerrado biome has been a global biodiversity hotspot with high rates of native vegetation suppression and wildfires over the past three decades. The samples collected in the Cerrado biome were located in the Serra Azul State Park. Currently visitation to the Park is constant by residents and tourists. Considering that a person with multibacillary leprosy eliminates an estimate of 107 bacilli per day through nasal secretions, the survival of the agent in the environment and the high rates of leprosy in the state of Mato Grosso, the historical anthropic impact in the region that remains can favor the maintenance of the microorganism in the environment and consequent infection of the individuals who live there. The true risk to human health from contact with M. leprae-infected small non-volant mammals has not yet been shown in the literature. The degree to which leprosy in the human population can be attributable to contact with small non-volant mammals depends on the magnitude of the risk, the type and frequency of contact or consumption, how common these practices are in the population, the role of other (human-to-human) transmission routes for M. leprae, and the immunological susceptibility of the individual. Palavras-chave: RLEP, RLPM, spleen, mammals, biomes Agência de fomento:CAPES | |||||