Infection of the equine population by Leishmania parasites.

Infection of equids by Leishmania (L.) parasites was previously described in both the Old and New World, particularly in Central and South America. Equine cutaneous leishmaniasis (CL) is caused by the Leishmania species, L. Viannia (V.) braziliensis and L. infantum, previously identified in humans and other parasite hosts living in the same geographic endemic areas. Sporadic autochthonous clinical cases, with no travel history, were documented in several countries including Germany, Portugal, Spain, Texas and Brazil; L. infantum and L. (Mundinia) martiniquensis were the infectious species. Prevalence of subclinical infections is extremely low and CL is observed in only a small proportion of infected animals with the appearance of single or multiple cutaneous lesions located on the head, external ear, scrotum, legs and the neck. To date, there has been no report of visceral abnormalities. However, the mild clinical profile of the disease and its spontaneous regression may indicate that skin lesions related to Leishmania infection is underdiagnosed. Importantly, although the prevalence of Leishmania infections in the equine population is low, a risk may rise from its potential involvement in the parasite transmission cycles as a source of infection for phlebotomine vectors and susceptible mammalian hosts. This review article summarises our current knowledge of the epidemiology, clinical presentation and diagnosis of Leishmania-infected equids.

Evidence of natural infections with Trypanosoma, Anaplasma and Babesia spp. in military livestock from Tunisia.

Livestock constitute habitual hosts and carriers for several infectious pathogens which may represent a serious public health concern affecting the readiness of military forces and lead to wide economic losses. The present report aimed to investigate the prevalence of some haemopathogens infecting military livestock, particularly, dromedaries, sheep and horses using Giemsa-stained blood smears. A total of 300 animals (100 from each species) were selected, clinically examined and sampled. Trypanosoma spp. (22.0%), Anaplasma spp. (17.0%) and Babesia spp. (1.0%) were identified in camels' blood. Six dromedaries were found to be co-infected by Trypanosoma and Anaplasma organisms (6.0%). Camels of female gender, infested by ticks and showing clinical signs were statistically more infected by Trypanosoma spp., compared to those of male gender, free of ticks and apparently healthy (P= 0.027, 0.000 and 0.004, respectively). Babesia spp. infection (1.0%) was identified, for the first time in Tunisia, in one adult female camel that presented abortion and anemia. Anaplasma spp. was the only haemopathogen identified in examined sheep (6.0%) and horses (17.0%). Horses infested by Hippobosca equina flies and sheep infested by Rhipicephalus turanicus ticks were more infected by Anaplasma spp. than other non-infested animals (P=0.046 and 0.042, respectively). Hyalomma dromedarii, H. impeltatum and H. excavatum were the most prevalent diagnosed ticks removed from camels with an intensity of infestation of 1.2 ticks per animal. However, in sheep, only R. turanicus was identified. H. equina and Tabanus spp. were the potential hematophagous flies found in dromedaries and horses herds. This useful data must be taken into consideration during animal treatment and vectors' control programs in Tunisian military farms which help to limit the diffusion of vector-borne diseases, keep our livestock healthy and reduce economic losses.

Evidence of natural infections with Trypanosoma, Anaplasma and Babesia spp. in military livestock from Tunisia

@#Livestock constitute habitual hosts and carriers for several infectious pathogens which may represent a serious public health concern affecting the readiness of military forces and lead to wide economic losses. The present report aimed to investigate the prevalence of some haemopathogens infecting military livestock, particularly, dromedaries, sheep and horses using Giemsa-stained blood smears. A total of 300 animals (100 from each species) were selected, clinically examined and sampled. Trypanosoma spp. (22.0%), Anaplasma spp. (17.0%) and Babesia spp. (1.0%) were identified in camels’ blood. Six dromedaries were found to be co-infected by Trypanosoma and Anaplasma organisms (6.0%). Camels of female gender, infested by ticks and showing clinical signs were statistically more infected by Trypanosoma spp., compared to those of male gender, free of ticks and apparently healthy (P= 0.027, 0.000 and 0.004, respectively). Babesia spp. infection (1.0%) was identified, for the first time in Tunisia, in one adult female camel that presented abortion and anemia. Anaplasma spp. was the only haemopathogen identified in examined sheep (6.0%) and horses (17.0%). Horses infested by Hippobosca equina flies and sheep infested by Rhipicephalus turanicus ticks were more infected by Anaplasma spp. than other non-infested animals (P=0.046 and 0.042, respectively). Hyalomma dromedarii, H. impeltatum and H. excavatum were the most prevalent diagnosed ticks removed from camels with an intensity of infestation of 1.2 ticks per animal. However, in sheep, only R. turanicus was identified. H. equina and Tabanus spp. were the potential hematophagous flies found in dromedaries and horses herds. This useful data must be taken into consideration during animal treatment and vectors’ control programs in Tunisian military farms which help to limit the diffusion of vector-borne diseases, keep our livestock healthy and reduce economic losses.

Epidemiological survey of vector-borne infections in equids from northern Tunisia.

Leishmaniosis (Leishmania infantum infection) and piroplasmoses (Theileria equi and Babesia caballi infections) are vector-borne diseases with significant economic and public health impacts. Despite their importance, there is a lack of data concerning these infections in equids from Tunisia. The present study was carried out to estimate the prevalence of L. infantum, T. equi and B. caballi in 104 equids from northern Tunisia. The authors reported for the first time on the seroprevalence of anti-Leishmania antibodies in equids in Tunisia (6.7%). The study reported a high infection prevalence of piroplasms (23.1%), revealed for the first time T. equi and B. caballi infections in Tunisian donkeys, and showed that these animals act as reservoirs for the maintenance and dissemination of piroplasms.

La leishmaniose (infection à Leishmania infantum) et les piroplasmoses (infections à Theileria equi et à Babesia caballi) sont des maladies à transmission vectorielle dont les conséquences économiques et l'impact sur la santé publique sont significatifs. Malgré leur importance, en Tunisie la situation des équidés vis-à-vis de ces maladies était jusqu'à présent peu documentée. L'étude décrite par les auteurs avait pour objet d'estimer la prévalence des infections à L. infantum, T. equi et B. caballi chez 104 chevaux du Nord de la Tunisie. La recherche d'anticorps dirigés contre Leishmania a permis de déterminer pour la première fois une prévalence sérologique chez les équidés (6,7 %). L'étude a rapporté une prévalence élevée de piroplasmes (23,1 %) et fait état pour la première fois en Tunisie de l'existence d'infections à T. equi et à B. caballi chez des ânes ; elle montre également que ces derniers font office de réservoirs et jouent un rôle dans le maintien et la dissémination des piroplasmes.

La leishmaniosis (infección por Leishmania infantum) y las piroplasmosis (infecciones por Theileria equi y Babesia caballi) son enfermedades transmitidas por vectores que tienen una importante repercusión en la economía y la salud pública. A pesar de su importancia, existen pocos datos sobre estas infecciones en los équidos tunecinos. Los autores describen un estudio destinado a estimar la prevalencia de L. infantum, T. equi y B. caballi en 104 équidos del norte del país, gracias al cual determinaron por primera vez la seroprevalencia de anticuerpos contra Leishmania en équidos tunecinos (un 6,7%). La investigación puso de manifiesto una elevada prevalencia de la infección por piroplasmas (un 23,1%), reveló por vez primera la infección de asnos tunecinos por T. equi y B. caballi y demostró que estos animales ejercen de reservorio, manteniendo y propagando así los piroplasmas.

Leishmaniosis (Leishmania infantum infection) in dogs.

The authors present an overview of canine leishmaniosis due to Leishmania infantum. This protozoan is transmitted by sandflies and the disease is frequently characterised by chronic evolution. Cutaneous and visceral clinical signs appear as the infection progresses. Lymph node enlargement, emaciation and skin lesions are the main signs observed in the classical forms of the disease. Control is difficult since infected dogs remain carriers for years and may relapse at any time. The mass screening of infected animals and their treatment or euthanasia represent the best way to reduce the prevalence of this disease in endemic regions. Further research is needed to improve the efficiency of the vaccines available to protect dogs against infection. This disease is zoonotic; in humans, clinical cases are reported mainly in elderly people, the young and those whose immune systems have been compromised.

Theileria parasites secrete a prolyl isomerase to maintain host leukocyte transformation.

Infectious agents develop intricate mechanisms to interact with host cell pathways and hijack their genetic and epigenetic machinery to change host cell phenotypic states. Among the Apicomplexa phylum of obligate intracellular parasites, which cause veterinary and human diseases, Theileria is the only genus that transforms its mammalian host cells. Theileria infection of bovine leukocytes induces proliferative and invasive phenotypes associated with activated signalling pathways, notably JNK and AP-1 (ref. 2). The transformed phenotypes are reversed by treatment with the theilericidal drug buparvaquone. We used comparative genomics to identify a homologue of the peptidyl-prolyl isomerase PIN1 in T. annulata (TaPIN1) that is secreted into the host cell and modulates oncogenic signalling pathways. Here we show that TaPIN1 is a bona fide prolyl isomerase and that it interacts with the host ubiquitin ligase FBW7, leading to its degradation and subsequent stabilization of c-JUN, which promotes transformation. We performed in vitro and in silico analysis and in vivo zebrafish xenograft experiments to demonstrate that TaPIN1 is directly inhibited by the anti-parasite drug buparvaquone (and other known PIN1 inhibitors) and is mutated in a drug-resistant strain. Prolyl isomerization is thus a conserved mechanism that is important in cancer and is used by Theileria parasites to manipulate host oncogenic signalling.

Interaction between canine and human visceral leishmaniases in a holoendemic focus of Central Tunisia.

Canine visceral leishmaniasis (CVL) is endemic in the Mediterranean basin. In Tunisia, CVL is spatially associated with human visceral leishmaniasis (HVL) affecting mostly children younger than 5 years old. In this study, seroprevalence of Leishmania infantum infection in dogs was assessed in highly endemic districts of the governorate of Kairouan where more than 50% of HVL cases in Tunisia were reported. An entomological investigation was also carried out in two endemic districts (Bouhajla and Haffouz) to assess sand fly fauna and infection status of sand flies with Leishmania. A total of 191 serum samples were collected from healthy dogs and tested for anti-L. infantum antibodies by indirect immunofluorescence antibody test (IFAT). Overall seroprevalence for L. infantum was 26.7% being highest among dogs in the district of Bouhajla (52.7%) and the lowest in the district of Chbika (5.2%). In dogs, seroprevalence did not differ significantly based on gender or age, with dogs younger than 1 year showing a higher seroprevalence compared to older dogs. These findings suggest strong force of infection in naïve animals in holoendemic regions leading to emerging high incidence of HVL. Concomitant to the high CVL prevalence observed in the Bouhajla district, a significantly high cumulative HVL incidence also was observed in this district. Phlebotomus perniciosus and Phlebotomus longicuspis were the most abundant sand fly species in Bouhajla and Haffouz districts. The rate of Leishmania-DNA infection in sand flies was 9.4%. This finding points to spatial correlation between the occurrence of disease in humans, a high rate of infection in dogs and a high abundance of P. pernicious and P. longicuspis. Thus, CVL is the main risk factor for transmission to humans and subsequently, it is an important parameter for controlling transmission to humans.

[Detection of Toxoplasma gondii infection of sheep slaughtered in the governorate of Sousse on the occasion of the Muslim sacrifice feast (Eid Al-Adha) and analysis of risk factors]. / Détection de l'infection par Toxoplasma gondii des ovins abattus dans le gouvernorat de Sousse (centre-est de la Tunisie) à l'occasion de la fête musulmane du sacrifice (Aïd Al-Adha) et analyse des facteurs de risque.

During the Muslim feast of Sacrifice (Eid Al-Adha), DNA of Toxoplasma gondii was screened in the heart apex of 70 sheep belonging to different households in Sousse region (North-East of Tunisia) by nested PCR.DNA of T. gondii was identified in 5.7% of the samples. To study different risk factors of Toxoplasma gondii transmission that can be present especially for this occasion, a questionnaire was established. It revealed that the majority of households (92.9%) slaughtered a sheep aged less than 1 year old. Moreover, 2% of the study population consumed undercooked meat. This study showed also that the majority of meat handlers did not respect the hygiene rules, since 91% of them did not wash their hands after handling and before preparing or consuming food. The presence of the definitive host (cats) is considered among the factors that increase the risk of Toxoplasma infection. It was recorded in 14% of the households with the presence of elements that increases the risk as defecating in the house and eating raw meat during Eid Al-Adha feast. Our results show that the risk factors of Toxoplasma infection increase during this occasion; it requires the establishment of a sanitary education programme during this feast.