- Autores: Campino L, Maia C
- Ano de Publicação: 2018
- Journal: Drug Resistance in Leishmania Parasites
- Link: https://link.springer.com/chapter/10.1007/978-3-319-74186-4_3
Canine leishmaniasis caused by Leishmania (Leishmania) infantum species (syn. L. (L.) chagasi species in Latin America), which is transmitted by the bite of phlebotomine sand flies, is endemic and affects millions of dogs in Asia, Europe, North Africa, and South America and is considered as an emergent disease in North America. Domestic dogs (Canis familiaris) are the major hosts for these parasites and the main reservoir host for human infection.
Recent years have seen important advances on the epidemiology, pathology, and canine genetic factors linked with animal resistance or susceptibility to leishmaniasis. Despite the lack of pathognomonic manifestations, infection by Leishmania can be suspected if a combination of clinical signs is present, namely, lymphadenomegaly, cutaneous alterations, loss of body weight, ocular disturbs, epistaxis, onychogryphosis, and lameness. However, the definitive diagnosis of canine leishmaniasis is complex since not all infected animals develop signs of disease. This fact cannot be ignored since asymptomatic (without clinical signs) dogs are infectious to phlebotomine vectors, although at a lower risk than symptomatic (with clinical signs) dogs. The fact that dogs never achieve parasitological cure together with the widespread use of the available anti-Leishmania drugs for both canine and human treatment certainly contributes to the spread of drug-resistant parasites with the natural consequences for the clinical outcome of the disease.
Early detection of infection and close surveillance or treatment of infected animals together with the development of effective molecules for therapy (ideally different from the ones used for humans) and, more importantly, for immunoprophylaxis are essential to control the dissemination of the disease among other dogs, being also a crucial element for the control of human zoonotic leishmaniasis.
This chapter reviews the role of dogs as reservoir hosts of L. (L.) infantum and as accidental hosts of other Leishmania species, as well as the role of other mammals as potential reservoir hosts of parasites belonging to the L. (L.) donovani complex. The potential generation and spread of drug resistance by the use of the same compounds in both canine and human hosts are also discussed.