Peridomestic small Indian mongoose: An invasive species posing as potential zoonotic risk for leptospirosis in the Caribbean.

In this study, we investigated Leptospira infection and exposure in small Indian mongoose (Herpestes auropunctatus), an invasive animal species, in two different sites in the Caribbean island of Saint Kitts. Overall a low seroprevalence (12/148; 8.1%: 95%CI: 3.7-12.5) was observed. Agglutinating antibodies to serovars Mankarso (3.4%), Copenhageni (2.7%), Icterohemorrhagiae (1.4%), Bratislava (1.4%), Canicola (1.4%), Autumnalis (0.7%), Alexi (0.7%), Pomona (0.7%) and Grippotyphosa (0.7%) was observed on the microscopic agglutination test. The seroprevalence observed in mongooses trapped from peridomestic sites was significantly higher compared to the arid and less inhabited site (p = 0.0268). The real time PCR targeting lipL32 gene was positive for 9 out of 146 mongooses. Bacterial culture of kidneys resulted in two Leptospira isolates. Whole genome sequencing and analysis suggested that these isolates are closely related to L. interrogans serovar Copenhageni. We observed mild to severe chronic renal lesions in 20.2% of mongooses in the absence of an antibody response or active infection. Our findings emphasize the need to investigate other infectious etiologies or atypical outcomes and potential chronic long-term impact of Leptospira infection in animals and people living in an endemic area. In addition, our data reinforces the need for including locally prevalent Leptospira isolates rather than representative members of a serogroup in the microscopic agglutination test panel in epidemiologic and diagnostic investigations. In conclusion, mongoose inhabiting the island are exposed to and harbor pathogenic Leptospira and hence may play a role in the transmission. The invasive nature of the species highlights their presence as a potential risk factor for this widespread zoonotic disease.