The present paper summarizes prevalence, epidemiology and clinical disease of natural Toxoplasma gondii infections in humans and animals from Egypt. The current situation of toxoplasmosis in Egypt is confusing. There is no central laboratory or group of researchers actively investigating toxoplasmosis in humans or animals, and no reports on the national level are available. Based on various serological tests and convenience samples, T. gondii infections appear highly prevalent in humans and animals from Egypt. Living circumstances in Egypt favour the transmission of T. gondii. Up to 95% of domestic cats, the key host of T. gondii, are infected with T. gondii; they are abundant in rural and suburban areas, spreading T. gondii oocysts. Many women have been tested in maternity clinics, most with no definitive diagnosis. Toxoplasma gondii DNA and IgM antibodies have been found in blood samples of blood donors. Clinical toxoplasmosis in humans from Egypt needs further investigations using definitive procedures. Reports on congenital toxoplasmosis are conflicting and some reports are alarming. Although there are many serological surveys for T. gondii in animals, data on clinical infections are lacking. Here, we critically review the status of toxoplasmosis in Egypt, which should be useful to biologist, public health workers, veterinarians and physicians.
The purpose of the present study was to obtain sarcocysts of Sarcocystis buffalonis and Sarcocystis levinei from water buffaloes and characterize the isolates by molecular methods in order to determine whether the two species were genetically different from Sarcocystis hirsuta and Sarcocystis cruzi, respectively, from cattle, which had been characterized before. About 35 macroscopically visible (3-4 × 1-2 mm) and 20 barely visible (1-3 × 0.2 mm) sarcocysts were excised from the esophagus of 18 naturally infected and freshly slaughtered adult water buffaloes at three slaughterhouses in Egypt. Genomic DNA was extracted from the sarcocysts, and all isolates were first characterized at the mitochondrial cytochrome c oxidase subunit I gene (cox1) gene through PCR amplification and direct sequencing. Selected isolates were subsequently further characterized at the 18S and 28S ribosomal (r) RNA genes and the internal transcribed spacer 1 (ITS1) region of the nuclear rDNA unit by direct sequencing or cloning. Only six of the isolated macroscopic sarcocysts belonged to S. buffalonis, whereas the others belonged to Sarcocystis fusiformis. Twelve of the smaller cysts belonged to S. levinei and seven to Sarcocystis sinensis. The characterization of the sarcocysts of S. sinensis and some of the sarcocysts of S. fusiformis have been reported before. Fifteen additional sarcocyst isolates of S. fusiformis were characterized at cox1 in the present study and found to be identical or closely similar to previous isolates. At cox1, the sequence identity between the six isolates of S. buffalonis was 99.8-100 % (two haplotypes), whereas the identity between the 12 isolates of S. levinei was 99.0-100 % (10 haplotypes). The identity between cox1 sequences of S. buffalonis and S. hirsuta (n = 56) was 92.9-93.6 % (on average 93.4 %), and the identity between cox1 sequences of S. levinei and S. cruzi (n = 22) was 92.9-94.0 % (on average 93.5 %). The phylogenetic analyses placed with high support the cox1 sequences of S. buffalonis and S. hirsuta into two monophyletic sister groups, and the same was true for the cox1 sequences of S. levinei and S. cruzi. Hence, the study established that S. buffalonis and S. levinei are distinct species different from S. hirsuta and S. cruzi, respectively. Nucleotide sequences of S. buffalonis could be distinguished from those of S. hirsuta also at the 28S rRNA gene (clearly different) and the ITS1 region (small and uncertain difference) but not at the 18S rRNA gene. Sequences of S. levinei could be distinguished from those of S. cruzi both at the 18S and 28S rRNA genes (ITS1 region not examined). However, the cox1 gene was superior to the 18S and 28S rRNA genes as regards the ability to unambiguously delimit the species within each species pair, since at the latter markers, the number of consistent nucleotide differences between the species was low and there was a slight overlap between the intraspecific and interspecific sequence divergence. Comparison of the newly generated 18S rRNA gene sequences of S. l...
BackgroundToxoplasmosis is a zoonotic disease that affects a wide range of animals, including small ruminants. Sheep and goats are considered as biological indicators for the contamination of the environment with Toxoplasma gondii oocysts. In addition, in countries such as Egypt, where sheep and goat meat is frequently consumed, T. gondii infection in small ruminants may also pose a public health risk. To establish baseline estimates of the prevalence of T. gondii infection in Egyptian small ruminants, we used an indirect immunofluorescence assay (IFA) and an enzyme-linked immunosorbent assay (ELISA) to assess the seroprevalence in 398 sheep from four Egyptian governorates (Cairo, Giza, Dakahlia and Sharkia) and in 100 goats from Dakahlia. The positive and negative agreements of both tests were calculated and the true prevalence was estimated using a Bayesian approach.ResultsThe true prevalence of antibodies to T. gondii as determined by both tests was higher in Egyptian goats (62%) than in sheep for each province (between 4.1 and 26%). Sheep slaughtered at the Cairo abattoir had the lowest true prevalence (4.1%), while true prevalences in Dakahlia, Giza and Sharkia governorates (26%, 23% and 12%, respectively) were substantially higher.ConclusionsThe high prevalence of antibodies to T. gondii may indicate an important role of goat and sheep in the transmission of human toxoplasmosis in Egypt, given the habit of eating undercooked grilled mutton.
SummaryThere is considerable confusion concerning Sarcocystis species in camels. Five species:Sarcocystis cameli, S. ippeni, S. camelicanis, S. camelocanis, and S. miescheri were named with inadequate descriptions and no type specimens. Here, we review literature on sarcocystosis in camels worldwide and redescribe structure of S. cameli and S. ippeni sarcocysts by light and transmission electron microscopy (LM, TEM). Eight sarcocysts from the esophagi of two camels (Camelus dromedarius) from Egypt were studied. By LM all sarcocysts were thin walled with barely visible projections on the cyst walls. By TEM, two structurally distinct sarcocysts were recognized by unique villar protrusions (vp) not found in sarcocysts from any other host.Sarcocysts of S. cameli had vp of type 9j. The sarcocyst wall had upright slender vp, up to 3.0 μm long and 0.5 μm wide; the total thickness of the sarcocyst wall with ground substance layer (gs) was 3.5 μm. On each vp there were rows of knob-like protrusions that appeared to be interconnected. The vp had microtubules that originated at mid point of the gs and continued up to the tip; microtubules were smooth, without any granules or dense areas. Bradyzoites were approximately 14-15 x 3-4 μm in size with typical organelles. Sarcocystis ippeni sarcocysts had type 32 sarcocyst wall characterized by conical villar protrusions with an electron dense knob.The total thickness of the sarcocyst wall (from the base of gs to vp tip) was 2.3-3.0 μm. The vp were up to 1.2 μm wide at the base and 0.25 μm at the tip. Microtubules in vp originated at midpoint of gs and continued up to tip; microtubules were criss-crossed, smooth and without granules or dense areas. Bradyzoites were 12.0-13.5 x 2.0-3.0 μm in size. Sarcocystis camelicanis, S. camelocanis, and S. miescheri are considered invalid.
A systematic study was undertaken to identify the species, characterize the pathogenicity, and assess the immunization of Eimeria bateri in Japanese quail ( Coturnix coturnix japonica). In total, 107 Japanese quail farms were examined. The samples were processed and oocyst shape indices of sporulated oocysts were determined. Out of 107 examined farms, 34 (31.78%) farms were positive. Four Eimeria spp. were morphologically identified. For characterization of the pathogenicity, Japanese quail were orally inoculated with various doses of sporulated oocysts of Eimeria bateri. Weight gain, feed conversion ratio (FCR), mortality, severity of diarrhea, and intestinal lesion scores were examined. The birds inoculated with high doses displayed significantly lower weight gain and poorer FCR, increased mortality, and more intestinal and fecal lesions scores. To quantify the immunization of Japanese quail against coccidiosis, 2-day-old quail were orally inoculated with either 100 or 1,000 sporulated oocysts of E. bateri. At 30 days of age, the immunized and non-immunized challenged birds were orally inoculated with 1 × 10 sporulated oocysts of E. bateri. After challenge, birds immunized with 100 or 1,000 oocysts had better weight gain, FCR, minimal diarrhea, fewer intestinal lesions, and lesser oocyst production compared to non-immunized challenged birds. We concluded that vaccination is a viable method for controlling coccidiosis in Japanese quail.
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