Prevalence of Trypanosoma evansi in livestock in Palestine

Abstract

Background: Trypanosoma evansi is the causative agent of surra, a disease that occurs in many animal species. The disease is responsible for substantial losses in global production and can be fatal if not diagnosed early. This study aims to determine the prevalence of T. evansi in livestock, equids and dromedary camels in Palestine. Methods: Blood samples were collected during 2015-2017 from domesticated animals (n = 259 animals; 77% females and 23% males) including camels (n = 87), horses (n = 46), donkeys (n = 28), mules (n = 2), sheep (n = 49) and goats (n = 48) from eight districts: Ariha (Jericho), Nablus, Bethlehem, Deir Al Balah, Jenin, Rafah, Tubas, and Khan Yunis. Parasite prevalence was determined using PCR and blood smear microscopy. PCR-positive samples were further phylogenetically analyzed using DNA sequences of the 18S ribosomal RNA gene. Results: The overall infection prevalence was 18% (46/259). The positivity rates according to PCR and microscopy examination were 17% (45/259) and 2.7% (7/259), respectively. The infection rates were as follows: camels, 26/61 (30%); horses, 8/46 (17%); donkeys, 3/28 (11%); mules, 1/2 (50%); sheep, 2/42 (4%); and goats, 6/42 (13%). Phylogenetic analyses of the 18S rRNA gene showed that 24 positive T. evansi samples from Palestine formed a monophyletic cluster with seven T. evansi sequences from Africa, Asia and South America, and three T. brucei sequences from Africa retrieved from GenBank. The spatial analysis showed three statistically significant foci of T. evansi infection in Jenin, Tubas (P = 0.02) and Ariha (Jericho) (P = 0.04). No statistically significant foci were detected in the Gaza Strip. Conclusions: To the best of our knowledge, this is the first confirmation of high levels of infection with T. evansi as a causative agent of surra in Palestine. Our study emphasizes the need for a stringent surveillance system and risk assessment studies as prerequisites for control measures. Further investigations focusing on vectors and evaluation of risk factors are needed.

First report of bovine anaemia associated Theileria sinensis infection and phylogenetic analyses of partial gene sequences of Theileria and Anaplasma species detected in naturally infected Malaysian cattle

“…Theileriosis, anaplasmosis, hemoplasmosis and trypanosomosis are economically important vectorborne diseases of cattle, usually characterized by high morbidity and high mortality in clinical cases [1][2][3][4]. These diseases are ranked among the most common causes of economic losses in livestock industry [2].…”

First report of the presence of Trypanosoma evansi in dogs from Paraguay applying molecular techniques

“…An experimental study in mice showed that real-time PCR is twice as sensitive for the detection of T. evansi than conventional parasitological techniques (Sharma et al, 2012). The most widely used molecular markers for the detection of this parasite are fragments of the ITS-1 (Eberhardt et al, 2014;Njiru et al, 2005;Sharma et al, 2012), variant surface glycoprotein (VSG) (Konnai et al, 2009) and 18S rRNA genes (Ereqat et al, 2020).…”

Trypanosoma evansi evades host innate immunity by releasing extracellular vesicles to activate TLR2-AKT signaling pathway

“…Wild mammals, such as puma and feral pigs, can also be infected with T. evansi [ 5 , 6 ]. T. evansi caused diseases are widely distributed in South America, Asia, Africa, and other regions, causing significant economic losses [ 7 ]. Since 2005, several cases of human infection by T. evansi have been reported [ 8–10 ], suggesting the potential of this parasite to be considered as zoonotic [ 11 ].…”