Dear Editor:
Leprosy, a disease neglected in many countries, is endemic in Brazil. With a wide diversity of fauna distributed in three biomes (Amazon Forest, Cerrado and Pantanal), the state of Mato Grosso (MT) in the Central-West Region has the highest prevalence of human cases: 7.75 per 10,000 inhabitants.11 Brasil. Ministério da Saúde. Secretaria de Vigilância em Saúde. Departamento de Vigilância Epidemiológica. Sistema de Informação de Agravos de Notificação; 2016. Despite the scarcity of data in the literature on wild animals naturally infected with Mycobacterium leprae, the possibility of transmission to humans cannot be ruled out. Armadillos, red squirrels, and non-human primates are important natural reservoirs of M. leprae reported in the literature, becoming possible sources of bacillary dissemination making it difficult to interrupt the leprosy transmission chain.22 Avanzi C, Del-Pozo J, Benjak A, et al. Red squirrels in the British Isles are infected with leprosy bacilli. Science. 2016;354:744-7. As data on natural infections are scarce, it is difficult to understand the role of wild animals in transmission of the disease. Therefore, we used PCR to detect the genetic material of M. leprae in nasal swabs of wild animals.
Nasal swabs were collected from 69 captive and free wild animals from the MT and Pantanal regions of Brazil, independent of clinical signs, and sent to the Laboratory of Microbiology and Molecular Biology, according to “Sistema de Autorização e Informação em Biodiversidade” (SISBIO), an authorization and information system for biodiversity (nos. 40617-1 and 42303). The samples were submitted for extraction of genetic material according to the phenol/chloroform method. PCR was performed according to Woods and Cole.33 Woods SA, Cole ST. A family of dispersed repeats in Mycobacterium leprae. Mol Microbiol. 1990;4:1745-51. The PCR product was purified using a GFX™ PCR DNA and Gel Band Purification kit (GE Healthcare, Piscataway, NJ, USA) and sequenced using an ABI-PRISM 3500 Genetic Analyzer (Life Technologies Corporation, USA). The sequences were deposited in GenBank and compared using the BLAST program (http://www.ncbi.nlm.nih.gov/blast/Blast.cgi). Of the 69 samples (Table 1), six (8.69%) wild-type free and captive animals tested positive for M. leprae by PCR, including one margay (Leopardus wiedii), two lowland tapirs (Tapirus terrestris), two capuchin monkeys (Sapajus apella), and one owl monkey (Aotus trivirgatus). The detection in four different species of wild animals shows the ability of this bacillus to be carried in different hosts. In addition, two animals were from the zoo, that could have acquired M. leprae due to close contact to humans or environmental contamination. However, in literature the mechanism of transmission is not yet fully understood.44 Turankar RP, Lavania M, Singh M, Sengupta U, Sai KSRS, Jadhav RS. Presence of viable Mycobacterium leprae in environmental specimens around houses of leprosy patients. Indian J Med Microbiol. 2016;34:315-21.
Epidemiological data and M. leprae PCR test of the animals identified in Mato Grosso - Brazil.
Knowledge of the environment surrounding the infected humans or animals, and route of infection and mode of transmission are necessary to understand endemics in certain regions.44 Turankar RP, Lavania M, Singh M, Sengupta U, Sai KSRS, Jadhav RS. Presence of viable Mycobacterium leprae in environmental specimens around houses of leprosy patients. Indian J Med Microbiol. 2016;34:315-21. Truman et al.55 Truman RW, Pushpendra S, Sharma R, et al. Probable zoonotic leprosy in the southern United States. N Engl J Med. 2011;364:1626-33. described that isolates from human and armadillos are identical genetically. Thus, we suggest that the possible contact of animals of this study, which may be possible carriers of the bacillus, with other animals or with humans can disseminate the disease, the bacillus was detected in nasal swabs. Thus, we observe that the detection in wild animals may be associated with high prevalence and endemicity in the state of MT, which makes them important sources of infection. In addition, these data contribute to a better understanding of the epidemiology of leprosy.
Disclaimers
The opinions expressed by authors contributing to this journal do not necessarily reflect the opinions of the Centers for Disease Control and Prevention or the institutions with which the authors are affiliated.
Acknowledgments
The authors are grateful to CAPES for financial support through a scholarship.
REFERENCES
-
1Brasil. Ministério da Saúde. Secretaria de Vigilância em Saúde. Departamento de Vigilância Epidemiológica. Sistema de Informação de Agravos de Notificação; 2016.
-
2Avanzi C, Del-Pozo J, Benjak A, et al. Red squirrels in the British Isles are infected with leprosy bacilli. Science. 2016;354:744-7.
-
3Woods SA, Cole ST. A family of dispersed repeats in Mycobacterium leprae Mol Microbiol. 1990;4:1745-51.
-
4Turankar RP, Lavania M, Singh M, Sengupta U, Sai KSRS, Jadhav RS. Presence of viable Mycobacterium leprae in environmental specimens around houses of leprosy patients. Indian J Med Microbiol. 2016;34:315-21.
-
5Truman RW, Pushpendra S, Sharma R, et al. Probable zoonotic leprosy in the southern United States. N Engl J Med. 2011;364:1626-33.
Publication Dates
-
Publication in this collection
Sep-Oct 2018
History
-
Received
21 Aug 2018 -
Accepted
24 Sept 2018
