Authors

T Carvalho Pereira²; F SouzaL SantosR WalkerT BahienseE M da SilvaM G ReisF CostaM Begon²;  ¹ Centro de Pesquisas Gonçalo Moniz, Fundação Oswaldo Cruz, Ministério da Saúde, Salvador, 40296-710, Brazil;  ² Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB;  ³ Instituto de Biologia, Universidade Federal da Bahia (UFBA), Salvador, 40170-290, Brazil;  ⁴ Instituto de Ciências da Saúde, UFBA, Salvador, 40.110-100, Brazil;  ⁵ Instituto de Saúde Coletiva, UFBA, Salvador, 40.110-040, Brazil

Discussion

We describe associations of helminths and the bacterium Leptospira interrogans in a population of Rattus norvegicus from an urban slum in Salvador-Brazil, highly affected by human leptospirosis. We sampled rat urine and kidney imprints, to identify/quantify L. interrogans. Fecal samples were analyzed to identify/quantify helminth species. Statistical models were applied to identify significant associations between the presence and intensity of each helminth species and L. interrogans with environmental factors, and demographic and condition variables of the rats. Focusing on coinfection, infection with the nematode Angiostrongylus cantonensis was negatively associated with infection with the helminths Nippostrongylus brasiliensis and Heterakis spumosa. The intensity of A. cantonensis was higher at higher intensities of Strongyloides sp.. None of the helminth species significantly increased the probability or intensity of L. interrogans infection.  Human infection by A. cantonensis can cause eosinophilic meningitis, an emergent disease in Brazil. Our findings highlight the need to deepen our knowledge of the risk factors associated with this helminth infection in the brown rat. It is also necessary to build an interaction network with the other helminth species to understand the dynamics of parasites in the field.