Study of an outbreak of cutaneous leishmaniasis in Venezuela: the role of domestic animals

Abstract

During an outbreak of cutaneous leishmaniasis in a locality (Las Rosas, Cojedes State, Venezuela) previously non-endemic, 12.9% of humans, 7% of dogs and 21.4% of donkeys (Equus asinus) had lesions with parasites. The agent in the three hosts was identified as Leishmania braziliensis, subspecies braziliensis at least in man and donkey. The probable vector was Lutzomyia panamensis. No infection was found in a small sample of wild mammals examined. The outbreak was apparently linked with the importation of donkeys with ulcers, from endemic areas. The authors call attention to the fact that not only in the foci of "uta", but also in areas of the other forms of American cutaneous leishmaniasis, dogs are frequently found infected. They emphasize the necessity of searching for the infection in donkeys and of performing hemocultures and xenodiagnosis with sandflies in human, canine and equine cases, to verify their possible role as sources of infection, and not merely as dead ends in the epidemiological chain of the disease.

Ecology of the Leishmania Species in the Guianan Ecoregion Complex

“…In Venezuela, donkeys (Equus asinus), dogs, and cats have been reported infected. [167][168][169][170] The importance of dogs as a reservoir of this parasite has been reported. 171 In Venezuela, the transmission seemed to occur peri-domestically by Lu.…”

“…panamensis, and some investigators have suggested that infected equines with ulcers imported from disease-endemic areas are an important factor in parasite dissemination in a peridomestic area where these sand flies are abundant. 57,168 Conversely, wild reservoir hosts of L. (V.) braziliensis are not well known and the primary reservoir of this parasite in the GEC has not been determined because of the vast area of South America. Several pathogenic complexes and their corresponding epidemiologic cycles may be present.…”

Tentativa de controle da leishmaniose tegumentar americana por meio do tratamento dos cães doentes

“…(V.) braziliensis, sugerindo a participação desse animal no ciclo de transmissão da moléstia (Aguilar et al, 1984(Aguilar et al, , 1989Pons & Londres, 1968). Apesar das evidências de que os animais domésticos possam servir de fonte de infecção para o homem, existem, até o momento, poucos estudos sobre o assunto.…”

Peridomiciliary Breeding Sites of Phlebotomine Sand Flies (Diptera: Psychodidae) in an Endemic Area of American Cutaneous Leishmaniasis in Southeastern Brazil

“…38,39 Several authors hypothesize the occurrence of a domiciliary transmission cycle of ACL involving humans and domestic animals, especially dogs and horses. 3,4,9,12,40 The discovery of peridomiciliary breeding sites of sand fly vectors of L. (V.) braziliensis supports this hypothesis, suggesting that they are able to survive and transmit Leishmania in areas devoid of forests. Even with the number of sand flies collected being relatively low, the results were relevant; since the entire monitored area (covered by the 60 m radius) was sampled, the estimations show the emergence of more than 2,000 phlebotomine sand flies per day.…”

“…The devastation of forests has altered the epidemiological characteristics of ACL throughout South and Central America. [2][3][4][5] In areas of ancient colonization in Southeastern (SE) Brazil, the disease now occurs in peri-urban areas where the forest is not close to residences, affecting adults and children of both sexes. Dogs and horses are frequently found to be infected with Leishmania (Viannia) braziliensis, [6][7][8][9] and the association between human and canine cutaneous leishmaniasis has already been shown in residences where people live with infected dogs 4,10,11 ; in these areas, sand flies are found in high densities in and around houses.…”