A systematic review of frequency and geographic distribution of water-borne parasites in the Middle East and North Africa.

Background: Water-borne parasitic infections are caused by pathogenic parasites found in water. These parasites are often not well-monitored or reported, therefore, there is an underestimation of their prevalence. Aims: We systemically reviewed the prevalence and epidemiology of water-borne diseases in the Middle East and North Africa (MENA) Region, which has a population of about 490 million people distributed over 20 independent countries. Methods: Online scientific databases, mainly PubMed, ScienceDirect, Scopus, Google Scholar, and MEDLINE were searched for the main water-borne parasitic infections in MENA countries during 1990-2021. Results: The main parasitic infections were cryptosporidiosis, amoebiasis, giardiasis, schistosomiasis, and toxocariasis. Cryptosporidiosis was the most frequently reported. Most of the published data were from Egypt, the country with the highest population in MENA. Conclusions: Water-borne parasites are still endemic in many MENA countries, however, their incidence has reduced dramatically due to the control and eradication programmes in countries that could afford such programmes, some with external support and funding.

Prevalence of and risk factors for Enterobius vermicularis infestation in preschool children, West Bank, Palestine, 2015.

BACKGROUND: Enterobius vermicularis (pinworm) infestation is a common condition that primarily affects children. AIMS: The aim of this study was to assess the prevalence of and the risk factors for E. vermicularis infestation in preschool children in north West Bank. METHODS: A cross-sectional study that included the six main governorates in north West Bank was carried out on a sample of 384 preschool children from 86 day-care centres. The perianal cellophane tape method was used to detect E. vermicularis infestation. Parents/guardians of participating children completed a questionnaire to collect information about: demographic characteristics; hygiene behaviour; socioeconomic status; history of previous infestation; and presence of symptoms. Risk factors for infestation were assessed using logistic regression analysis. RESULTS: Of the 384 children, 85 (22.1%) had E. vermicularis infestation. Age (P = 0.04), governorate (P = 0.01), residency (P = 0.03), number of household members (P < 0.001) and washing hands after toilet use (P = 0.01) were significantly associated with E. vermicularis infestation. In the logistic regression analysis, factors that increased the probability of infection were: living in villages (odds ratio (OR) 2.25; 95% confidence interval (CI): 1.01-5.00), living in a household with ≥ nine family members (OR 3.63; 95% CI: 1.42-9.26) and not washing hands after using the toilet (OR 2.4; 95% CI: 1.30-4.40). CONCLUSIONS: E. vermicularis is an important helminthic infestation among preschool children in Palestine. Efforts are needed to ensure the availability of treatment for infected children at primary care centres and to reinforce hygiene behaviour.

The Prevalence of Gastrointestinal Parasites in Native Dogs in Palestine.

BACKGROUND: Dogs play an important role in transmission of parasites and zoonotic diseases, especially in developing countries. We aimed to investigate the prevalence of internal parasites in stray and pet dogs in Palestine. METHODS: Fecal samples were collected during the period between Jan to May 2019. A total of 150 fecal samples were collected and tested for parasites using sedimentation and flotation techniques. The targeted dogs were both pet dogs and stray dogs and were grouped according to gender and age. RESULTS: Although there was no significant difference in infestation between males and females, the prevalence rate of infestation in males was 63.1% compared to females 72.4%. Dogs of ages under one year had similar rate of infestation compared to older dogs with a rate of 67.3% and 67.4% respectively. Infestations were significantly higher (P<0.05) in stray dogs 81.4% compared to pet dogs 48.4%. The highest infestation rate was with Toxocara canis 46.0% followed by Dipylidium caninum 23.0%, Echinococcus spp. 14.0% ,Isosopora canis 9.0%, Ancylostoma caninum 8.0%, Giarda spp. 5.0%, Strongyloides spp. 4.0%, Trichuris vulpis 3.0%, and Cryptosporidium spp. 3.0%. CONCLUSION: Local dogs in Palestine, especially stray dogs, are infested with different types of intestinal parasites that may cause many common and non-common diseases to humans. To prevent the spread of these parasites, future public health should be proposed and applied by authorities to achieve a healthy status of the residents in the country. Health awareness spread among people about the seriousness of the diseases transmitted by dogs must also be activated.

Meat-borne parasites in the Arab world: a review in a One Health perspective.

Meat-borne parasitic zoonoses are generally not well-monitored, and so understanding extent and overall prevalence is problematic. Without sufficient attention, their prevalence can become unexpectedly and unacceptably high. This review sheds light on meat-borne parasites in the Arab world, which includes all the Arab countries situated in the continents of Asia and Africa, with more than 400 million inhabitants distributed in 22 countries. Meat-borne parasites can be divided into two main categories-helminths and protozoa. The main helminths included in this review are Taenia saginata, Taenia solium, Taenia asiatica, Echinococcus spp., Fasciola spp., and Trichinella spiralis, while the meat-borne protozoan parasites are Toxoplasma gondii, Cryptosporidium spp., and Sarcocystis spp. In addition, Linguatula serrata, which belongs to the class Pentastomida, was included. Among those, the genus Taenia is the most frequently reported in the Arab world, particularly T. saginata. Many parasitic infections that are mainly transmitted through pork, although widespread in many parts of the world, are rare in the Arab countries, primarily due to religious proscriptions. The majority of the publications concerning meat-borne parasites were from Egypt, which contains the largest population in the Arab world and the highest population density, in addition to various economic, social, and environmental reasons.

Genetic Characterization of Taenia saginata Cyst Isolates from Germany.

The beef tapeworm Taenia saginata, which causes taeniosis in humans and cysticercosis in cattle, is of medical and economic importance. Understanding the parasite's genetic population structure may help to analyze transmission patterns and aid in the development of control measures. As information on sequence variability is scarce for European isolates, this study aimed to elucidate the intraspecific genetic variability of T. saginata cysts from German cattle by sequence comparison of the mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 5 (nad5) genes, in relationship to sequences from other geographical origins. Cysts were collected from northern German, Swiss, and Belgian cattle. Moreover, proglottids from an adult T. saginata specimen from Palestine were included. Amplification and Sanger sequencing of the cox1 gene was successful for 57 samples (45 German, 9 Swiss, 2 Belgian, 1 Palestinian), whereas 32 sequences were obtained for the nad5 gene (21 German, 10 Swiss, 1 Palestinian). For German isolates, sequence comparison revealed minor genetic variability with two polymorphic sites and mutations in both genes. Three haplotypes with haplotype diversity of 0.088 for cox1 and 0.186 for nad5, as well as nucleotide diversities of 0.00028 and 0.00095, respectively, were observed. Comparison of the cox1 gene sequence of German isolates with other European, African, American, and Asian isolates obtained from National Center for Biotechnology Information (total of 71 sequences) raised 11 polymorphic sites and mutations as well as 10 haplotypes (haplotype diversity: 0.239; nucleotide diversity: 0.00097). Although nad5 sequence comparison comprised less sequences (N = 33), analyses revealed 11 polymorphic sites, 12 mutation sites, and 7 haplotypes (haplotype diversity: 0.335, nucleotide diversity: 0.00391), indicating a better resolution of genetic variability compared to cox1. Thus, nad5 may be particularly useful for in-depth studies on genetic divergence of T. saginata.

Genetic diversity of Taenia hydatigena in the northern part of the West Bank, Palestine as determined by mitochondrial DNA sequences.

Cysticercus tenuicollis is the metacestode of canine tapeworm Taenia hydatigena, which has been reported in domestic and wild ruminants and is causing veterinary and economic losses in the meat industry. This study was conducted to determine the sequence variation in the mitochondrial cytochrome c oxidase subunit 1 (coxl) gene in 20 isolates of T. hydatigena metacestodes (cysticercus tenuicollis) collected from northern West Bank in Palestine. Nine haplotypes were detected, with one prevailing (55%). The total haplotype diversity (0.705) and the total nucleotide diversity (0.0045) displayed low genetic diversity among our isolates. Haplotype analysis showed a star-shaped network with a centrally positioned common haplotype. The Tajima's D, and Fu and Li's statistics in cysticercus tenuicollis population of this region showed a negative value, indicating deviations from neutrality and both suggested recent population expansion for the population. The findings of this study would greatly help to implement control and preventive measures for T. hydatigena larvae infection in Palestine.

Molecular characterization of Echinococcus granulosus isolated from sheep in Palestine.

A total of twenty-three Echinococcus granulosus hydatid cysts were collected from infected sheep slaughtered in Nablus abattoir, Nablus - Palestine. Protoscoleces or germinal membranes were used for DNA extraction followed by PCR amplification. Amplified products were analyzed the presence of a fragment of 444bp of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene followed by nucleotide sequencing. Overall, 21 hydatid cysts were positive compared to a negative control. The partial sequences of cox1 gene of E. granulosus strains indicated that the sheep in Palestine were infected with genotype 1 (G1), genotype 2 (G2) and genotype 3 (G3). The prevalence of these genotypes was (14/21) 66.7%, (4/21) 19.0% and (3/21) 14.3% for G1, G2 and G3, respectively. Our results showed that twelve strains of G1 belonged to the common haplotype EG01 which is the major haplotype in all the geographic populations. Phylogenetic analysis also showed that two sequences of G1 genotype which have GenBank accession No. KC109657 and KC109659 were corresponding to G1.4 micro-variants. Only the sequence of GenBank accession No. KC109652 identified in our study as G2 was found to have complete identity to the original sequence described for the cox1 gene (GenBank accession No. M84662). It is concluded that G1 genotype is the predominant genotype in sheep in Palestine. Therefore, these findings should be taken into consideration in developing prevention strategies and control programs for hydatidosis in Palestine.

An immunoblot for detection of Taenia saginata cysticercosis.

Control measures to prevent human infections with the food-borne zoonotic helminth Taenia saginata are currently based on meat inspection, which shows rather low diagnostic sensitivity. To develop an immunoblot for detection of T. saginata-infected cattle, crude proteins of T. saginata cysts were extracted and separated with SDS-PAGE. The cyst antigens showed ten protein bands ranging from 260 to 14 kDa. T. saginata cyst proteins 260, 150, 130, 67, 60, 55, 50, and 23 kDa were immunoreactive with known positive sera of T. saginata-infected cattle but cross-reacted with sera from Echinocccus granulosus-infected ruminants. By contrast, 14- and 18-kDa cyst proteins reacted specifically with T. saginata-positive sera and thus might be potential candidates for the development of a T. saginata-specific immunoassay. Proteins of E. granulosus cysts and Taenia hydatigena cysts were also extracted and separated with SDS-PAGE. E. granulosus cysts revealed 11 protein bands ranging from 260 to 23 kDa. E. granulosus protein 60 kDa was immunoreactive with E. granulosus-positive sera only. The cyst of T. hydatigena showed 11 protein bands ranging from 290 to 14 kDa. The protein band 35 kDa showed cross-reaction with positive sera from both T. saginata- and E. granulosus-infected animals. A protein of 67 kDa was present in all three tested cestode species and was the major antigenic protein detected by sera of T. saginata- and E. granulosus-infected animals. Therefore, this protein represents a potential vaccine candidate against both cysticercosis and cystic echinococcosis in cattle.

Seroprevalence of Taenia saginata cysticercosis in the federal state of Lower Saxony in Germany.

Based on ELISA results from randomly selected serum samples taken from 128 cattle from different administrative and urban districts in the federal state of Lower Saxony in Germany a seroprevalence estimate of Taenia saginata cysticercosis in this area was derived. This estimate was subsequently used to calculate the sample size required in an epidemiological study to determine the actual prevalence of this infection in the cattle population (n = 2 604 767) in this federal state. The sample size was calculated as 1518 and the samples were collected according to the distribution of cattle among the 48 administrative and urban districts in Lower Saxony. The samples were tested with an evaluated antibody ELISA. The results showed a positive antibody titre rate of 8.83% from the total tested samples.