Animal Trypanosomiasis in South America: Current Status, Partnership, and Information Technology

Abstract

Animal trypanosome species of economical importance in South America include T. vivax and T. evansi. Both species are described in Brazil, Bolivia, Colombia, French Guyana, Peru, Suriname, and Venezuela. In Argentina and Guyana, only T. evansi and T. vivax are found, respectively. Our studies on T. vivax indicated that the parasite was spreading around 1.3 km per day in Bolivia. We found severe leukopenia in bovines from Pantanal (Brazil) and the Department of Santa Cruz (Bolivia). Because it can cause immunosupression, the importance of trypanosomiasis control in ensuring success of vaccination campaigns against foot and mouth disease (FMD) in the Pantanal and Bolivia should be considered. The use of one needle for several animals during FMD campaigns in Brazil and Bolivia could also contribute to the spread of T. vivax. The anticipated losses due to T. vivax could exceed $160 million, assuming there are 11 million head of cattle in the Brazilian Pantanal and Bolivian lowlands. International collaboration among research institutes is needed to deal with these diseases and parasites. Previous efforts using information technologies resulted in the creation of two discussion lists (Tryplink and Trypan), the edition of the on‐line version of Trypnews and Internet conferences.

Surtos de tripanossomíase por Trypanosoma evansi em eqüinos no Rio Grande do Sul: aspectos epidemiológicos, clínicos, hematológicos e patológicos

“…No passado, T. evansi foi também denominado T. equinum, T. hippicum e T. venezuelense (Hoare 1972). No Brasil, T. evansi afeta principalmente eqüinos e a prevalência da infecção varia de região para região (Dávila & Silva 2000, Herrera et al 2004. A doença é enzoótica em eqüinos do Pantanal matogrossense, onde assume importância econômica devido à grande população de eqüinos (49.000) da região (Silva et al 1995a, Aquino et al 1999.…”

“…Embora existam vários trabalhos que descrevem a tripanossomíase em eqüinos no Brasil (Franke et al 1994, Silva et al 1995a,b, Dávila et al 1999, Dávila & Silva 2000, Seidl et al 2001, Silva et al 2002, inclusive com a reprodução experimental da doença (Marques et al 2000, Lemos 2003, há ainda lacunas na epidemiologia e patologia da tripanossomíase em eqüinos no país. No presente trabalho, descrevem-se surtos de tripanossomíase por T. evansi que resultaram na morte de pelo menos 100 eqüinos no Rio Grande do Sul.…”

Evaluation of animal performance, feed intake, and economic losses in sheep experimentally infected with Trypanosoma vivax

“…In South America, the parasite has adapted to mechanical transmission by hematophagous dipterans, such as Stomoxys spp. and insects of the Tabanidae family (DÁVILA; SILVA, 2000). In Brazil, trypanosomiasis from T. vivax has already been reported in several states, and the expansion of trypanosomiasis throughout the country may have been favored by the movement of bovine herds (LINHARES et al, 2006).…”

Evaluation of clinical signs, parasitemia, hematologic and biochemical changes in cattle experimentally infected with Trypanosoma vivax

“…Trypanosoma brucei, T. congolense, T. vivax and T. evansi cause significant losses in livestock, and T. vivax is responsible for large economic losses of cattle in Africa, Asia and Central and South Americas (HOARE, 1972). In South America, the most important species of trypanosomes are T. cruzi, etiologic agent of Chagas disease in humans and dogs, T. evansi, causing neurological disorders in horses and other mammals and T. vivax that causes deaths and infertility in ruminants (DÁVILA & SILVA, 2000).…”