Prevalence of Mycobacterium leprae in armadillos in Brazil: A systematic review and meta-analysis

Abstract

Understanding the prevalence of M. leprae infection in armadillos is important because of evidence from Brazil and other countries of an association between contact with armadillos and the development of Hansen's Disease (leprosy). Our aim was to characterize studies which have investigated natural M. leprae infection in wild armadillos in Brazil, and to quantify and explore variability in the reported prevalence of infection. We conducted a systematic review (PROSPERO CRD42019155277

Zoonotic risk of Hansen's disease from community contact with wild armadillos: A systematic review and meta‐analysis

“…We found that living or working in armadillo‐inhabited areas increased HD risk by 39%, albeit with relatively weak evidence of an association. The average prevalence (by meta‐analysis) of M. leprae infection in wild armadillos in Brazil was equivalent to 1 in 10 armadillos being infected, albeit with wide variation (Deps et al., 2020). Recent studies have reported similar overall prevalences in multiple states in the USA (Ploemacher et al., 2020).…”

“…Further studies like those reviewed here are unlikely to further greatly our understanding of HD risk in relation to armadillo capture and consumption in communities. We would argue that it has been established beyond reasonable doubt that armadillos carry M. leprae infection in endemic and non-endemic American countries (Deps et al, 2020;Truman et al, 2011), and that this poses a risk to human health. A wide variety of contact with armadillos through hunting, butchering, cooking and consumption has been described among residents of the state of Ceará, in north-eastern Brazil (Kerr et al, 2015).…”

“…Whilst Hansen's disease (HD) is classified as zoonotic in the USA, with recommendations regarding contact with armadillos (CDC), no recommendations have been made in other countries of the Americas which have a higher endemic burden of HD and extensive armadillo populations known to carry Mycobacterium leprae infection (Deps et al., 2020). In some of these countries, hunting, handling and eating armadillos is a common if unlawful practice (Kerr et al., 2015).…”

One Health and Hansen’s disease in Brazil

“…This research needs to be transdisciplinary, under the umbrella of One Health, encompassing social and anthropological research to understand community practices in relation to contact with wild armadillos [14], ecological studies in partnership with conservation groups to map and characterize transmission of M. leprae and its persistence within armadillos [11,12,29], and genomic studies to determine the relatedness of M. leprae strains infecting humans and animals [8,17]. A better understanding of pathways to infection, including that these might not be from person to person, is also important in destigmatising disease.…”

“…Brazil is within the range of several armadillo species which inhabit the Amazon, Atlantic Forest, and semiarid ecosystems [11]. Natural infection of wild armadillos by M. leprae has been reported across Brazil, equivalent to 1 in 10 animals being infected with the bacillus [12]. All armadillo species are protected in Brazil, and some are critically endangered [13], but their habitats are dwindling in size and disturbed by human activity, and illegal hunting to obtain meat for private consumption and commercial sale is widespread [11].…”