Emergent and Neglected Equine Filariosis in Egypt: Species Diversity and Host Immune Response.

Equine filariosis (EF) is a neglected vector-borne disease caused by nematode species belonging to the Onchocercidae and Setariidae families. Aside from their zoonotic potential, some species are responsible for serious health problems in equids worldwide, leading to significant economic difficulties. Here, we molecularly investigated equine blood samples (320 horses and 109 donkeys from Egypt) and four adult worms isolated from the peritoneal cavity of 5 out of the 94 slaughtered donkeys. In addition, quantitative enzyme-linked immunoassays (ELISAs) targeting circulating cytokines were used to identify whether the immunological profile of the infected animals is a Th1 (i.e., INF-gamma as indicator) or Th2 (i.e., IL-5 and IL-10 as indicators) response type. Overall, 13.8% and 0.3% of the donkeys and horses, respectively, were scored as positive for filaroid DNA. The 18S phylogeny revealed the occurrence of three different filaroid species, identified here as Mansonella (Tetrapetalonema) sp., Setaria digitata and Dirofilaria repens. Th1 (INF-gamma and IL-5) and Th2 (IL-10) immune response types were identified in equines infected with S. digitata and Mansonella (T.) sp., respectively. These results provide new data on the species diversity of EF in Egypt and extend knowledge of the downregulation of the protective immune response by the potentially zoonotic Mansonella (T) sp. There is an urgent need to implement control measures to preserve equine health and limit the propagation of these vector-borne filaroids in Egypt.

Scanning electron microscopy and morphometrics of nymph and larva of the tick Hyalomma impressum (Acari: Ixodidae).

Nymphs and larvae of ixodid ticks play an important role on the distribution of ticks and transmission of pathogens. They almost infest small mammals and birds which either move from place to place as rodents or migrate across different countries as migratory birds. The morphological descriptions of nymph and larva of the tick Hyalomma impressum were firstly studied in details by scanning electron microscopy and morphometric analysis. The distinguished characters of H. impressum nymph are as follows: dorsal idiosoma (excluding scutum) with 26-27 pairs of setae, posterior margin of scutum is narrowly rounded, posterolateral margins of scutum is straight, cervical grooves on the scutum extend to the midlength, coxa I with two large spurs, coxae (II-IV) with one small spur for each, spiracle is an egg shape with a numerous pores, palpus does not project beyond the hypostome, with nine setae dorsally and six setae ventrally, hypostome has cylindrical shape, dental formula 2/2, teeth number per file is eight in the outer file and seven in the inner file, basis capitulum has triangular shape without setae dorsally and tetragonal shape with three pairs of setae ventrally. The distinctive characters of H. impressum larva are as follows: idiosoma with 13 pairs of setae for each dorsal (including scutal setae) and ventral (excluding coxal setae), scutum with cervical grooves is narrow and shallow extending about one third of the scutal length, posterior margin of scutum is broadly rounded, posterolateral margins of scutum is straight, fold-like indistinctive spurs on coxae II and III, palpus with eight setae dorsally, three setae ventrally and one seta apically, hypostome with dental formula 2/2, teeth number per file (excluding small basal and apical teeth) is seven in the outer file and six in the inner file, basis capitulum without setae dorsally and with three pairs of setae ventrally.

In vitro effect of artemether and triclabendazole on adult Fasciola gigantica.

Triclabendazole "Fasinex" is the drug of choice against fasciolosis because of its high efficacy against both mature and immature flukes, however parasite resistance against this drug is increasing. Hence, there is pressing need for new fasciolicidal drugs. In the present study, the in vitro effect of artemether on adult flukes was evaluated using scanning electron microscopy. After 24 h incubation with 10 microg/ml artemether, the tegument of the apical cone appeared to be slightly more swollen than normal. This swelling became so severe and the spines appeared sunken, with their tips protruding from a swollen and blebbed base, on increasing the concentration to 20 microg/ml. With the higher concentration of 30 microg/ml, extensive and severe tegumental swelling occurred in the apical cone region of the flukes. There were many blebs around ventral sucker, a number of which appeared to have burst causing lesion. The tegumental changes occurred following incubation in artemether were comparable with those observed with triclabendazole in its active sulphoxide metabolite form (TCBZ-SX).

In Vitro Assessment of Balanites aegyptiaca Fruit Methanolic Extract on the Adult Toxocara canis.

BACKGROUND: The effectiveness of anthelmintics may diminish within approximately 10 yr of use relying on several factors such as anthelmintic resistance. This study aimed to assess in vitro effect of Balanites aegyptiaca fruits extract on the cuticle of adult worm of Toxocara canis as naturally alternative therapy. METHODS: B. aegyptiaca fruits were procured from the local markets in Aswan, Upper Egypt and authenticated at the Herbarium of National Research Centre. The effect of methanolic extract of B. aegyptiaca fruits on adult T. canis after 24 and 48 h incubating the parasites in Ringer solution containing 240 µg/ml Balanites extract was determined by scanning electron microscopy. RESULTS: The main changes induced by treatment with the tested extract were wrinkled cuticular surface and deformed sensory papillae. This cuticular distortion would undoubtedly disrupt its protective function and might be enough to expel Toxocara worms from dog's intestine. CONCLUSION: The use of this plant offers a chance for new nematocidal agent, which is economical alternative for the more expensive anthelmintics.

Efficacy of some essential oils on Cephalopina titillator with special concern to nasal myiasis prevalence among camels and its consequent histopathological changes.

Nasopharyngeal myiasis is an important high incidence disease among camels in the Middle East and North of Africa caused by Cephalopina titillator (C. titillator) that results in sever economic losses in many camel breeding areas around the world. The current study was conducted to evaluate the efficacy of three essential oils; camphor, ginger and cinnamon oils and their histopathological effects on the 3rd larval instar of C. titillator, with special regard to the prevalence percentage of C. titillator infestation in slaughtered camels at Egyptian abattoirs in addition to investigate histopathological alterations of the infested animal's tissue. This study fulfilled that the prevalence of C. titillator infestation was 35.2% among slaughtered camels during summer season. The three tested essential oils were caused a significant mortality of C. tittilator; however, camphor oil was exhibited greater and quicker insecticidal effect than ginger and cinnamon oils at the same concentration in terms of mortality of the 3rd instar C. tittilator larvae. There was a concentration-dependent effect on the larvae among the tested essential oils. The tested essential oils were caused remarkable histopathological alterations on the treated larval cuticle. The main salient lesions of the examined infested camel's tissue were necrotic and inflammatory alterations associated with cystic dilation of submucosal glands.

Evaluation of different Haemonchus contortus antigens for diagnosis of sheep haemonchosis by ELISA and their cross reactivity with other helminthes.

Haemonchus contortus (H. contortus) remains important nematode that infecting sheep all over the world. Truthful diagnosis of haemonchosis needs reliable Enzyme linked immune sorbent assay test as well as the immuno-reactive protein profile of different prepared H. contortus antigens; larval (L), excretory secretory product (ESP) and adult somatic H. contortus (AS). The current study fulfilled that L antigen is the talented antigen for such serological diagnosis. Immunodominant band at molecular weight 57 kDa were answerable for highest specificity and accuracy of positive predictive value of this antigen. Moreover, the highest apparent prevalence value was 92 and 75% obtained by L and ESP antigens, respectively. The results of cross reactivity among AS, Monezia expansa (M. expansa) and Fasciola spp. revealed that AS antigen appeared major cross reactivity with other cestode and trematode. Best dilution of serum was (1:800) to rise above this phenomenon.

In vitro tegumental alterations on adult Fasciola gigantica caused by mefloquine.

Emergence of drug-resistant Fasciola strains has drawn the attention of many authors to alternative drugs. The purpose of this study is to explore the in vitro effect of the antimalarial mefloquine against adult Fasciola gigantica. Light and scanning electron microscopic observations could be used to determine the target of the drug following 6 and 12 h of incubation in medium containing mefloquine at three different concentrations 10, 20 and 30 µg/mL, as morphological changes could be observed. These changes occurred in definite sequences in response to mefloquine, and were consisted of swelling, vacuolization that was later disrupted, leading to desquamation of the tegument, resulting in exposure and disruption of basal lamina and the dislodging of spines. It is concluded that mefloquine presented itself as a drug that might become important in trematode chemotherapy, with the tegument being an important drug target.

Scanning electron microscopy and morphometrics of nymph and larva of the tick Hyalomma rufipes Koch, 1844 (Acari: Ixodidae).

The genus Hyalomma comprises the most ixodid tick species that parasitize camels in Egypt. Although the immature stages of tick species play an important role in distribution of ticks and tick-borne diseases, the identification depends mainly on the adult stage. Therefore, this study tries to identify the specific characteristics of both nymph and larva of Hyalomma rufipes Koch, 1844 using scanning electron microscopy and morphometric analysis in order to differentiate them easily from those of other Hyalomma spp. described before in Egypt. Results showed that the nymph and larva of H. rufipes can be easily identified from those of H. excavatum Koch, 1844, H. dromedarii Koch, 1844 and H. impressum Koch, 1844 but they are strongly close to H. marginatum Koch, 1844. The nymph of H. rufipes can be distinguished from H. marginatum by the number and distribution of dorsal and ventral idiosomal setae and the distribution of sternal setae. All morphological characteristics of H. rufipes larva resemble those of H. marginatum larva. The measurements of nymph and larva structures of H. rufipes are significantly lower than those of H. marginatum.

Larvicidal activity of camphor and lavender oils against sheep blowfly, Luciliasericata (Diptera: Calliphoridae).

In this study, the essential oils of camphor and lavender were tested in vitro against the third instar larvae of Lucilia sericata for the first time, following dipping toxicity technique. The toxicity results revealed that L. sericata larvae were susceptible to the applied essential oils. Lavender oil was more effective than camphor in killing of L. sericata larvae. With 32 % concentration, the mortality percentages of larvae were 100 and 93.3 %, respectively. Light and scanning electron microscopic examinations were done to determine the cuticular changes of L. sericata larvae following exposure to the applied essential oils. Larvae showed cuticular swelling and distortion after oil treatment, but its level was greater with lavender oil. The current study suggested that an alternative, effective and natural product can be developed as larvicides against L. sericata using camphor and lavender oils.

Assessment of Theileria equi and Babesia caballi infections in equine populations in Egypt by molecular, serological and hematological approaches.

BACKGROUND: Equine piroplasmosis (EP) caused by Theileria equi, Babesia caballi, or both, contributes to significant economic loss in the equine industry and remains uncontrolled in Egypt. This study focuses on surveying T. equi and B. caballi infections and hematological disorders in equine populations in Egypt. METHODS: Theileria equi and B. caballi infections were assessed in blood from 88 horses and 51 donkeys in Egypt using light microscopy, indirect immunofluorescent antibody test (IFAT), nested PCR (nPCR), and competitive-ELISA (cELISA) assays. PCR products were examined for specificity by DNA sequencing. Hematological alterations were evaluated using a standard cell counter. RESULTS: Microscopic analysis revealed EP infection in 11.4% and 17.8% of horses and donkeys respectively. IFAT detected 23.9% and 17.0% infection of T. equi and B. caballi, respectively, in horses, and 31.4% of T. equi and B. caballi in donkeys. T. equi cELISA detected 14.8% and 23.5% positive horses and donkeys, respectively, but the B. caballi RAP-1-based cELISA failed to detect any positives, a result hypothesized to be caused by sequence polymorphism found in the rap-1 genes. Nested-PCR analysis identified 36.4% and 43.1% positive horses and donkeys, respectively for T. equi and it also identified 19.3% and 15.7% positive horses and donkeys, respectively for B. caballi. The overall EP incidence found in the population under study was relatively high and comparable regardless of the diagnostic method used (56.8% using nPCR and 48.9% using IFAT). Hematologic analysis revealed macrocytic hypochromic anemia and thrombocytopenia in all piroplasma-infected horses. CONCLUSIONS: The data confirm relatively high levels of EP, likely causing hematological abnormalities in equines in Egypt, and also suggest the need for an improved serological test to diagnose B. caballi infection in this region.

Efficacy of methanolic extract of Balanites aegyptiaca fruits on Toxocara vitulorum.

In this study, the effect of the methanolic extract of Balanites aegyptiaca fruits (BAE) on adult Toxocara vitulorum was evaluated after incubating the parasites in Ringer solution containing 10, 30, 60, 120 and 240 µg/ml of the methanolic extract, for 24h using light and scanning electron microscopic observations. Differences in response to BAE action were concentration dependent. These changes occurred in definite sequences in response to BAE concentration and were consisted of slightly swelling which became pronounced and so severe, with lips showed wrinkled cuticular surface and deformed sensory papillae on increasing the BAE concentration. The strongest effects were reached with the highest BAE concentration, where disorganization of the cuticle and body musculature was observed. Additionally, the ovicidal effect of BAE, at the previous concentrations, on the development of T. vitulorum eggs was examined after 12h exposure. The inhibitory activity of BAE on egg development was concentration dependent and the highest value reached to 100% with the concentration of 240 µg/ml. These results were compared with those observed in the worm cuticle and eggs following incubation in albendazole, as it was a broad-spectrum nematodicidal compound with well-known ovicidal activity.