Leptospirosis at human-animal-environment interfaces in Latin-America: drivers, prevention, and control measures

Abstract

Leptospirosis is one of the main re-emerging zoonotic diseases with a worldwide distribution, mainly in regions with hot or tropical climates. It is caused by the spirochetal bacteria of the genus Leptospira, which, in their pathogenic life forms, causes asymptomatic to severe infections in humans and animals. Animal-to-human transmission occurs most frequently in occupationally exposed groups and in travelers. However, leptospirosis also represents a disease associated with poverty and low sanitation environments, in rural and urban communities, in close contact with companion animals and livestock. A search was performed in PubMed, Scopus, Web of Science and Google scholar databases using query terms related to Leptospira/leptospirosis, reported during 1990-2020. This review focuses on the description of biologic and socioenvironmental drivers that influence the occurrence of the disease in humans. Leptospirosis is found at the human-animal-environment interfaces, and represents a challenge for public and animal health, and food production; hence, improving the strategies for prevention control and surveillance in Latin-American countries is critical, as one of the regions most affected by the disease.

Modelling the Unidentified Abortion Burden from Four Infectious Pathogenic Microorganisms (Leptospira interrogans, Brucella abortus, Brucella ovis, and Chlamydia abortus) in Ewes Based on Artificial Neural Networks Approach: The Epidemiological Basis for a Control Policy

“…Owing to the lack of diagnostic laboratories and a limited reporting system, leptospirosis and brucellosis are one of several neglected diseases in Mexico, and this may be one of the reasons why few cases were identified over this period, despite the high carriage of multi microorganisms in animals. The occurrence of human leptospirosis cases is more common in the tropics, especially in South America and Asia [ 41 , 42 ], and in regions where brucellosis is endemic, deleterious effects are seen in both humans and domestic animals in the developing nations of Africa, South/Southeast Asia, and Latin America [ 43 ]. The appearance of zoonotic disease in new localizations, as well as the sources of transmission between wild and domestic animals, is of great importance in terms of the epidemiological dimension.…”

Leptospirosis and the Environment: A Review and Future Directions

“…Leptospira , both pathogenic and not, have been found in soils globally [ 8 , 56 , 57 , 62 , 64 , 95 , 101 , 102 , 103 , 104 , 105 , 106 , 107 , 108 , 109 ]. Contact with Leptospira in the soil is one of the leading routes of infection with leptospirosis, resulting in outbreaks across the globe [ 2 , 3 , 4 , 7 , 9 , 12 ]. As mentioned previously, outbreaks of leptospirosis following floods, storms, and other mass precipitation events have been documented globally [ 8 , 50 , 51 , 52 , 53 ].…”

“…Leptospira infections usually occur through abrasions or wounds in skin or through contact with mucosa [ 5 ]. Leptospira can be transmitted directly to humans through the handling of infected animals, making leptospirosis an occupational hazard for people that regularly handle animals, such as livestock producers, abattoirs, veterinarians, hunters and game managers, animal control workers, and scientists [ 1 , 2 , 3 , 4 , 7 , 9 , 10 , 11 ]. As the local prevalence of leptospirosis and the frequency of exposure to Leptospira determines the risk of infection for an individual, individuals in regions with increased workplace procedures and protections such as surveillance, diagnostic testing and treatment of infected animals, and access to personal protective equipment—such as gloves, goggles, and boots—are less likely to contract leptospirosis [ 1 , 3 , 4 , 7 , 11 , 12 , 13 ].…”

“…More commonly, leptospirosis is contracted indirectly through contact with contaminated water or soil [ 2 , 4 , 5 , 7 , 8 , 11 ]. As a result, leptospirosis remains an occupational hazard for individuals that work closely with soil and water systems, such as sewage and waste workers, construction, military, aquaculture workers, and farmers [ 1 , 4 , 7 , 8 , 9 , 11 , 12 , 14 , 15 , 16 , 17 , 18 ]. Leptospirosis is also a growing environmental hazard for outdoor recreationalists—such as kayakers, swimmers, fishermen, etc.…”

Domestic dogs in indigenous Amazonian communities: key players inLeptospiracycling and transmission?

“…A diverse array of domestic and wild animals likely serve as reservoirs by excreting Leptospira in their urine [13][14][15]. However, like humans, we know little about the prevalence and shedding of these pathogens in peridomestic animal hosts in rural settings [15][16][17][18][19][20], and reports indicating the seroprevalence of the pathogen in wild animals are even more scarce [21][22][23][24][25][26][27]. These important epidemiological parameters may be similar across regions, but site-specific attributes such as host densities and interactions (with human and non-human hosts) are likely highly important for the circulation and transmission of Leptospira [16].…”