Evidence for Wild Crocodiles as a Risk for Human Leptospirosis, Mexico

Abstract

Sentinel species such as crocodilians are used to monitor the health of ecosystems. However, few studies have documented the presence of zoonotic diseases in wild populations of these reptiles. Herein we analyzed 48 serum samples from Crocodylus acutus (n = 34) and C. moreletii (n = 14) from different sites in the state of Quintana Roo (Mexico) to detect antibodies to Leptospira interrogans by means of a microscopic agglutination test (MAT). Crocodylus acutus and C. moreletii tested positive to 11 and 9 serovars, respectively, with Grippotyphosa being the serovar with the highest prevalence in Cozumel island (100%), Banco Chinchorro Biosphere Reserve (70.6%), and Río Hondo (100%), while in Chichankanab Lake, it was Bratislava (75%). Titers ranged from 1:50 to 1:3200, and the most frequent was 1:50 in all study sites. Leptospira is present in fresh and saltwater individuals due to the resistance of the bacterium in both environments. Cases of infected people involved with crocodile handling and egg collection suggest that these reptiles could play an important role in the transmission of leptospirosis. Preventive medicine programs should consider the monitoring of reptiles, and testing the soil and water, to prevent outbreaks of leptospirosis in facilities containing crocodiles.

Blanding’s turtles (Emydoidea blandingii) as a reservoir for Leptospira spp

“…In South America, Oliveira et al reported a 16.7% (11/66) prevalence of Leptospira spp. from PCR samples collected from the stomach and cloaca of wild Phrynops geoffroanus in an urban environment in Brazil [14], and Biscola et al identified the serotype Interrogans from PCR samples of the liver and kidney from a wild Bothrops pauloensis [15]. In Africa, a wild Crotaphopeltis hotamboeia was positive for Leptospira spp.…”

Presence of anti-Leptospira spp. antibodies in captive yellow-spotted river turtles (Podocnemis unifilis) in the Eastern Amazon

“…In addition to regular serologic tests on animals to better understand the infection risk, hygienic and sanitary measures are necessary in captive environments. These include regular sanitization of enclosures, removal of synanthropic animals, analysis of water quality, and implementation of a quarantine period before the introduction of a new specimen (PÉREZ-FLORES et al, 2016;ESTEVES-MACHADO et al, 2010;RATAJ et al, 2011;RODRIGUES et al, 2016;DETTUZZO, et al, 2017;EBANI, 2017). Such measures can minimize pathogen incidence in zoos and other facilities were animals are held captive.…”

Investigating the Immunological and Biological Equilibrium of Reservoir Hosts and Pathogenic Leptospira: Balancing the Solution to an Acute Problem?

“…Other wild animals with documented culture positive cases include sea lions ( Acevedo-Whitehouse et al, 2003 ), deer ( Gay et al, 2014 ), snakes ( Ferris et al, 1961 ), as well as skunks and opossums ( Alexander et al, 1972 ). Serological evidence of exposure has been documented in feral swine, muskrat ( Al Saadi and Podt, 1976 ), elephants ( Oni et al, 2007 ), raccoons ( Allen et al, 2014 ), and crocodiles ( Pérez-Flores et al, 2017 ).…”