Dogs, cats, parasites, and humans in Brazil: opening the black box

Abstract

Dogs and cats in Brazil serve as primary hosts for a considerable number of parasites, which may affect their health and wellbeing. These may include endoparasites (e.g., protozoa, cestodes, trematodes, and nematodes) and ectoparasites (i.e., fleas, lice, mites, and ticks). While some dog and cat parasites are highly host-specific (e.g., Aelurostrongylus abstrusus and Felicola subrostratus for cats, and Angiostrongylus vasorum and Trichodectes canis for dogs), others may easily switch to other hosts, including humans. In fact, several dog and cat parasites (e.g., Toxoplasma gondii, Dipylidium caninum, Ancylostoma caninum, Strongyloides stercoralis, and Toxocara canis) are important not only from a veterinary perspective but also from a medical standpoint. In addition, some of them (e.g., Lynxacarus radovskyi on cats and Rangelia vitalii in dogs) are little known to most veterinary practitioners working in Brazil. This article is a compendium on dog and cat parasites in Brazil and a call for a One Health approach towards a better management of some of these parasites, which may potentially affect humans. Practical aspects related to the diagnosis, treatment, and control of parasitic diseases of dogs and cats in Brazil are discussed.

Figure 1

Human-animal bond. A homeless with his inseparable friends that were found abandoned in the streets of Porto Alegre, southern Brazil.

Figure 2

Poor living conditions. An owner and his dogs living in a poor rural community in Goiana, north-eastern Brazil, where visceral leishmaniosis is endemic. In poor rural communities people (as this man in the picture) are used to walking barefoot, which is a risk factor for bare feet-related diseases, such as cutaneous larva migrans and tungiasis.

Figure 3

Ectoparasites of dogs and cats. Line drawings for the identification of common dog and cat ectoparasites (fleas: A-F; lice: G-J and mites: K-P) found in Brazil. For details see Table 3).

Figure 4

Vector density. Hundreds of phlebotomine sand flies (Lutzomyia longipalpis) on a chicken (A) that was resting on a tree trunk in Passira, north-eastern Brazil, where visceral leishmaniosis is endemic. (B) shows a close-up of the phlebotomine sand flies

Figure 5

Environmental contamination with dog faeces. Stray dogs roaming freely in a beach in southern Brazil. Dog faeces are an important source of zoonotic parasites that may cause diseases such as cutaneous larva migrans.