Zoonotic parasites infecting free-living armadillos from Brazil.

Armadillos are specialist diggers and their burrows are used to find food, seek shelter and protect their pups. These burrows can also be shared with dozens of vertebrate and invertebrate species and; consequently, their parasites including the zoonotics. The aim of this study was to diagnose the presence of zoonotic parasites in four wild-caught armadillo species from two different Brazilian ecosystems, the Cerrado (Brazilian savanna) and the Pantanal (wetland). The investigated parasites and their correspondent diseases were: Toxoplasma gondii (toxoplasmosis), Trypanosoma cruzi (Chagas disease), Leishmania spp., (leishmaniasis), Paracoccidioides brasiliensis (Paracoccidioidomicosis) and Mycobacterium leprae (Hansen's disease). Forty-three free-living armadillos from Pantanal and seven road-killed armadillos from the Cerrado were sampled. Trypanosoma cruzi DTU TcIII were isolated from 2 out of 43 (4.65%) armadillos, including one of them also infected with Trypanosoma rangeli. Antibodies anti-T. gondii were detected in 13 out of 43 (30.2%) armadillos. All seven armadillos from Cerrado tested positive for P. brasiliensis DNA, in the lungs, spleen, liver fragments. Also, by molecular analysis, all 43 individuals were negative for M. leprae and Leishmania spp. Armadillos were infected by T. cruzi, T. rangeli, P. brasiliensis and presented seric antibodies to T. gondii, highlighting the importance of those armadillos could have in the epidemiology of zoonotic parasites.

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

Understanding and quantifying the risk of Hansen's disease (HD) through zoonotic transmission of Mycobacterium leprae infection from wild armadillos is important because hunting, handling and consumption of these animals is widespread in communities where HD is endemic, posing a potential threat to the health of individuals and to HD elimination. We conducted a systematic review (PROSPERO CRD42019159891) of publications in MEDLINE, EMBASE, Global Health, Scopus, LILACS, Biblioteca Digital Brasileira de Teses e Dissertações, Catálogo de Teses e Dissertações de CAPES, and Biblioteca Virtual em Saúde up to 09/05/2020 using Mesh and text terms in English, Portuguese, Spanish and French. Random effects meta-analyses were performed including of subgroups by endemicity and type of exposure. Seven of the nine included studies were case-control, four from Brazil and three from the USA, comprising 1,124 cases and 2,023 controls in total. The other two studies, one from Brazil and one from Colombia, were cross-sectional. The overall summary estimate (odds ratio, OR) for the relative odds of HD comparing people who had direct contact with armadillos and/or had eaten armadillo meat with those who had not was OR = 2.60 (95% CI 1.78-3.80, p < .001) with a predictive interval of OR = 1.10-6.17. Summary odds ratios for specific exposures were as follows: indirect contact, OR = 1.39 (95% CI 1.02, 1.89) (p = .04); eating, OR = 2.29 (95% CI 1.13, 4.66) (p = .02); hunting, OR = 2.54 (95% CI 1.21, 5.33) (p = .01). Most of the included studies had moderate risk of bias. Crude estimates were reduced by up to 24% when adjusted for confounders (where reported). Direct contact with wild armadillos was strongly associated with an increased risk of HD, whilst evidence for an increased risk of HD from indirect contact was weaker. The fraction of HD in endemic countries attributable to zoonotic transmission from armadillos remains unknown, but the precautionary principle needs to be adopted to protect public health.

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

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) of publications in MEDLINE, EMBASE, Global Health, Scopus, LILACS, Biblioteca Digital Brasileira de Teses e Dissertações, Catálogo de Teses e Dissertações de CAPES, and Biblioteca Virtual em Saúde up to 10/2019 using Mesh and text search terms (in English, Portuguese, Spanish, and French). The 10 included studies represented a total sample of 302 armadillos comprising 207 (69%) Dasypus novemcinctus, 67 (22%) Euphractus sexcinctus, 16 (5%) Priodontes maximus, 10 (3%) Cabassous unicinctus, and 2 (1%) Cabassous tatouay from 7 different states. Methods used included histopathology (4 studies), PGL-1 and LID-1 antigen detection (4 studies) and examination for clinical signs of disease (4 studies). Eight studies used PCR of which 7 targeted the RLEP repetitive element and 3 tested for inhibitory substances. M. leprae prevalence by PCR ranged from 0% (in 3 studies) to 100% in one study, with a summary estimate of 9.4% (95% CI 0.4% to 73.1%) and a predictive interval of 0-100%. The average prevalence is equivalent to 1 in 10 armadillos in Brazil being infected with M. leprae, but wide variation in sample estimates means that the prevalence in any similar study would be entirely unpredictable. We propose instead that future studies aim to investigate transmission and persistence of M. leprae within and between armadillo populations, meanwhile adopting the precautionary principle to protect human health and an endangered species in Brazil.

Serological and molecular detection of infection with Mycobacterium leprae in Brazilian six banded armadillos (Euphractus sexcinctus).

Leprosy was recognized as a zoonotic disease, associated with nine-banded armadillos (Dasypus novemcinctus) in the Southern United States of America in 2011. In addition, there is growing evidence to support a role for armadillos in zoonotic leprosy in South America. The current study evaluated twenty specimens of the six-banded armadillo (Euphractus sexcinctus), collected from rural locations in the state of Rio Grande do Norte (RN), Brazil for evidence of infection with Mycobacterium leprae. Serum was examined using two "in-house" enzyme-linked immunosorbent assays (ELISAs) and via two commercially available (ML flow and NDO-LID®) immunochromatographic lateral flow (LF) tests, for detection of the PGL-I and/or LID-1 antigens of the bacterium. The presence of M. leprae DNA in liver tissue was examined using the multi-copy, M. leprae-specific repetitive element (RLEP), as target in conventional and nested PCR assays. Molecular and anti-PGL-I-ELISA data indicated that 20/20 (100 %) of the armadillos were infected with M. leprae. The corresponding detection levels recorded with the LF tests were 17/20 (85 %) and 16/20 (85 %), for the NDO-LID® and ML flow tests, respectively. Our results indicate that, in common with D. novemcinctus, six banded armadillos (a species hunted and reared as a food-source in some regions of Brazil, including RN), represent a potential reservoir of M. leprae and as such, their role in a possible zoonotic cycle of leprosy within Brazil warrants further investigation.

Leprosy survey among rural communities and wild armadillos from Amazonas state, Northern Brazil.

There is evidence that in southern US, leprosy is a zoonosis infecting wild Dasypus novemcinctus armadillos but the extent of this finding is unknown. This ecological study investigated leprosy in rural communities and in wild armadillos from the Brazilian Amazon. The study area was the Mamiá Lake of Coari municipality, Amazonas State, Northern region, a hyper endemic leprosy area where residents live on subsistence farming, fishing and armadillo hunting and its meat intake are frequent. The leprosy survey was conducted in sixteen communities by a visiting team of specialists. Local partakers provided wild armadillos to investigate M. leprae infection. Volunteers had complete dermato-neurological examination by a dermatologist with expertise in leprosy diagnosis, suspect skin lesions were biopsied for histopathology (Hematoxylin-eosin/HE, Fite-Faraco/FF staining); slit skin smears were collected. Armadillos' tissue fragments (skins, spleens, livers, lymph nodes, adrenal glands, others) were prepared for histopathology (HE/FF) and for M. leprae repetitive element-RLEP-qPCR. Among 176 volunteers, six new indeterminate leprosy cases were identified (incidence = 3.4%). Suspect skin sections and slit skin smears were negative for bacilli. Twelve wild D. novemcinctus were investigated (48 specimens/96 slides) and histopathological features of M. leprae infection were not found, except for one skin presenting unspecific inflammatory infiltrate suggestive of indeterminate leprosy. Possible traumatic neuroma, granuloma with epithelioid and Langhans cells, foreign-body granuloma were also identified. Granulomatous/non-granulomatous dermatitides were periodic-acid-Schiff/PAS negative for fungus. M. leprae-RLEP-qPCR was negative in all armadillos' tissues; no bacillus was found in histopathology. Our survey in rural communities confirmed the high endemicity for leprosy while one armadillo was compatible with paucibacillary M. leprae infection. At least in the highly endemic rural area of Coari, in the Brazilian Amazon region where infectious sources from untreated multibacillary leprosy are abundant, M. leprae infected armadillos may not represent a major source of infection nor a significant public health concern.

Mycobacterium leprae and leprosy: a compendium.

Leprosy is a chronic infectious disease caused by Mycobacterium leprae, which was discovered by G.H.A. Hansen in 1873. M. leprae is an exceptional bacterium because of its long generation time and no growth in artificial media. Entire sequencing of the bacterial genome revealed numerous pseudogenes (inactive reading frames with functional counterparts in M. tuberculosis) which might be responsible for the very limited metabolic activity of M. leprae. The clinical demonstration of the disease is determined by the quality of host immune response. Th1-type immune response helps to kill the bacteria, but hosts are encroached upon when Th2-type response is predominant. The bacteria have affinity to the peripheral nerves and are likely to cause neuropathy. M. leprae/laminin-alpha2 complexes bind to alpha/beta dystroglycan complexes expressed on the Schwann cell surface. WHO recommends a chemotherapy protocol [multidrug therapy (MDT)] which effectively controls the disease and contributes to the global elimination program. Leprosy has been stigmatized throughout history, and recent topics regarding the disease in Japan are also discussed.

Nonhuman sources of leprosy.

Our findings establish that there are known extrahuman reservoirs of M. leprae in three animal species. There is considerable evidence that the armadillo plays a role in the epidemiology of leprosy in humans in Texas and Louisiana. The elimination of leprosy as a public health problem (defined by the World Health Organization as one active patient per 10,000 population) may be attainable by the wide application of current control measures; however, the ultimate eradication of leprosy must take into account extrahuman reservoirs of M. leprae. The impact that attempts to control or to eliminate leprosy in such reservoirs (e.g., the armadillo in Louisiana and Texas) would have on environmental and wild-life considerations would be profound. Whether or not similar situations prevail in other leprosy-endemic geographic areas is not known. Based on the armadillo experience, there seems to be ample justification for undertaking, forthwith, carefully designed surveys for enzootic leprosy in some of the major endemic areas of leprosy. At the current state of our knowledge of the subject, such surveys should be initiated in the natural habitats of the mangabey monkey and chimpanzees--in West Africa.