Helminth Parasites among Rodents in the Middle East Countries: A Systematic Review and Meta-Analysis

Rodent-borne parasites in Qatar: A possible risk at the human-animal-ecosystem interface

Rodents are known reservoirs for a diverse group of zoonotic pathogens that can pose a threat to human health. Therefore, it is crucial to investigate these pathogens to institute prevention and control measures. To achieve this, the current study was conducted to investigate the frequency of different parasites in commensal rodents in Qatar. A total of 148 rodents, including Rattus norvegicus, Rattus rattus, and Mus musculus were captured using traps placed in different habitats such as agricultural and livestock farms, residential areas, and other localities. Blood, feces, ectoparasite, and visceral organs were collected for gross, microscopic, immunological, and molecular analysis. The study identified 10 different parasites, including Capillaria annulosa, Eimeria spp., Giardia spp., Hymenolepis diminuta, Mastophorus muris, Ornithonyssus bacoti, Taenia taeniaeformis, Toxoplasma gondii, Trypanosoma lewisi, and Xenopsylla astia. Overall, 62.2% of the rodents tested positive for at least one parasite species. Helminths were found to be the most prevalent parasites (46.0%), followed by ectoparasites (31.8%), and protozoa (10.1%). However, individually, X. astia was the most prevalent (31.8%), whereas C. annulosa was the least common (0.7%). The prevalence of X. astia and H. diminuta significantly differed between habitats (p < 0.05). The sequence analysis of Hymenolepis spp. was closely related to the previously reported H. diminuta in Iran, China, and Mexico. In conclusion, the study identified a diverse range of rodent-borne parasites that are important to public health, with most of them being recorded for the first time among commensal rodents in Qatar.

Histopathological and morphological characterization of Cysticercus fasciolaris isolated from domestic and wild rodents in Morocco

Cysticercus fasciolaris is a parasitic helminth that usually infects feline and canine mammal hosts. The intermediate hosts (rodents, occasionally lagomorphs, and humans) get infected by the consumption of feed or water contaminated with eggs. Rodents are vectors of disease and reservoirs of various zoonotic parasites. The current survey was aimed at determining endoparasitic helminth infections in rodents in central Morocco. Sampled rodents after specific identification were sacrificed and examined to identify parasitic helminths following ethical guidelines. Parasites were identified using morphological characteristics. A total of 197 specimens of rodents were collected and examined in this study. Ten rodent species were identified morphologically as Rattus rattus, R. norvegicus, Apodemus sylvaticus, Mus musculus, M. spretus, Mastomys erythroleucus, Meriones shawi, M. libycus, Gerbillus campestris, and Lemniscomys barbarus. The parasitological results showed that metacestode of tapeworms was found encysted in the liver, the larval stage of Taenia taeniaeformis develops large multinodular fibrosarcomas which envelope the tapeworm cysts in the liver of the R. rattus and R. norvegicus. Based on morphological data, the metacestode was identified as C. fasciolaris in 23 (23/80) R. rattus 2 (2/8) and R. norvegicus with a prevalence of 11.7 % and 1.0 %, respectively. Rodents are major vectors of human and domestic animal diseases worldwide, and therefore, important parasitic zoonotic agents (C. fasciolaris), which are transmitted by black rats (R. rattus) and brown rats (R. norvegicus), must be considered to prevent the infectivity of humans, domestic animals, and livestock such as cattle, sheep, and rabbits.

Reply to Hamzavi et al. Comment on "Islam et al. Helminth Parasites among Rodents in the Middle East Countries: A Systematic Review and Meta-Analysis. Animals 2020, 10, 2342"

Rodents serve as an important reservoir or carrier of zoonotic pathogens on a global scale [...].

Comment on Islam et al. Helminth Parasites among Rodents in the Middle East Countries: A Systematic Review and Meta-Analysis. Animals 2020, 10, 2342

I read with great interest the article by Islam et al. entitled "Helminth parasites among rodents in the Middle East countries: a systematic review and meta-analysis" published in Animals in December 2020 [...].

Giardia duodenalis (Styles, 1902) in Cattle: Isolation of Calves with Diarrhoea and Manure Treatment in the Lagoon Presented as Risk Factors in Latvian Herds

Giardia duodenalis is a waterborne zoonotic protozoan that causes gastrointestinal tract inflammation in humans, cattle, and other animals. The aim of the present study was to estimate the prevalence and potential risk factors for Giardia infection in cattle in Latvia. During 2020-2021, a total of 973 individual faecal samples from cattle aged from 1 day to 12 years old, from 32 cattle herds, were tested for Giardia cyst presence with immunofluorescence staining followed by Giardia assemblage differentiation targeting beta-giardin gene. Using a questionnaire, information was collected to estimate the potential risk factors for G. duodenalis infection in cattle herds. Giardia was found in 8.4% of the examined cattle with a mean intensity of 5756 cysts per gram of faeces. The highest prevalence was observed in the 0 to 3-month-old calves (16.4%). At least one Giardia shedding animal was found in 27 herds with an overall prevalence of 84.4%. Significantly higher prevalence was found for cattle infected with G. duodenalis assemblage E compared to that infected with assemblage A: 88.7% and 11.3%, respectively. Protective factors such as age and rodent control and change of shoes were found to be significant for Giardia infection, while isolating calves for diarrhoea and water bodies (ponds/lakes) in pasture were potential risk factors in Latvian cattle.

Cancerogenic parasites in veterinary medicine: a narrative literature review

Parasite infection is one of the many environmental factors that can significantly contribute to carcinogenesis and is already known to be associated with a variety of malignancies in both human and veterinary medicine. However, the actual number of cancerogenic parasites and their relationship to tumor development is far from being fully understood, especially in veterinary medicine. Thus, the aim of this review is to investigate parasite-related cancers in domestic and wild animals and their burden in veterinary oncology. Spontaneous neoplasia with ascertained or putative parasite etiology in domestic and wild animals will be reviewed, and the multifarious mechanisms of protozoan and metazoan cancer induction will be discussed.

Global patterns of Middle East respiratory syndrome coronavirus (MERS-CoV) prevalence and seroprevalence in camels: A systematic review and meta-analysis

The Middle East respiratory syndrome Coronavirus (MERS-CoV) is one of the human coronaviruses that causes severe respiratory infection. Bats are considered to be the natural reservoir, where dromedary camels (DC) are the intermediate hosts of the virus. The current study was undertaken to provide an update on global distribution of the virus in camels, and to investigate the pooled prevalence and camel-associated risk factors of infection. After registration of the review protocol in the Open Science Framework, data searches were conducted on 18 April 2023 through Embase, PubMed, Scopus, and Web of Science. Considering only natural MERS-CoV infection in camels, 94 articles were selected for data curation through blind screening by two authors. Meta-analysis was conducted to estimate the pooled prevalence and to evaluate camel-associated risk factors. Finally, the results were presented in forest plots. The reviewed articles tested 34 countries, of which camels of 24 countries were seropositive and in 15 countries they were positive by molecular method. Viral RNA was detected in DC. Non-DC, such as bactrian camels, alpaca, llama, and hybrid camels were only seropositive. The global estimated pooled seroprevalence and viral RNA prevalence in DC were 77.53% and 23.63%, respectively, with the highest prevalence in West Asia (86.04% and 32.37% respectively). In addition, 41.08% of non-DC were seropositive. The estimated pooled prevalence of MERS-CoV RNA significantly varied by sample types with the highest in oral (45.01%) and lowest in rectal (8.42%) samples; the estimated pooled prevalence in nasal (23.10%) and milk (21.21%) samples were comparable. The estimated pooled seroprevalence in <2 years, 2-5 years, and > 5 years age groups were 56.32%, 75.31%, and 86.31%, respectively, while viral RNA prevalence was 33.40%, 15.87%, and 13.74%, respectively. Seroprevalence and viral RNA prevalence were generally higher in females (75.28% and 19.70%, respectively) than in males (69.53% and 18.99%, respectively). Local camels had lower estimated pooled seroprevalence (63.34%) and viral RNA prevalence (17.78%) than those of imported camels (89.17% and 29.41%, respectively). The estimated pooled seroprevalence was higher in camels of free-herds (71.70%) than confined herds (47.77%). Furthermore, estimated pooled seroprevalence was higher in samples from livestock markets, followed by abattoirs, quarantine, and farms but viral RNA prevalence was the highest in samples from abattoirs, followed by livestock markets, quarantine, and farms. Risk factors, such as sample type, young age, female sex, imported camels, and camel management must be considered to control and prevent the spread and emergence of MERS-CoV.

Rodent-borne viruses in the region of Middle East

Rodents are one of the most abundant mammal species in the world. They form more than two-fifth of all mammal species and there are approximately 4600 existing rodent species. Rodents are capable of transmitting deadly diseases, especially those that are caused by viruses. Viruses and their consequences have plagued the world for the last two centuries, three pandemics occurred during the last century only. The Middle East is situated at the crossroads of Africa and Asia, along with the Mediterranean Sea and the Indian Ocean, its geographic importance is gained through the diversity of topographies, biosphere, as well as climate aspects that make the region vulnerable to host emerging diseases. Refugee crises also play a major role in expected epidemic outbreaks in the region. Public health has always been the most important priority, and our aim in this review is to raise awareness among public health organisations across the Middle East about the dangers of rodent borne diseases that have been reported or are suspected to be found in the region.

Rodent Ectoparasites in the Middle East: A Systematic Review and Meta-Analysis

Rodents carry many ectoparasites, such as ticks, lice, fleas, and mites, which have potential public health importance. Middle Eastern countries are hotspots for many emerging and re-emerging infectious diseases, such as plague, leishmaniasis, Crimean Congo hemorrhagic fever, and Q fever, due to their ecological, socioeconomic, and political diversity. Rodent ectoparasites can act as vectors for many of these pathogens. Knowledge of rodent ectoparasites is of prime importance in controlling rodent ectoparasite-borne zoonotic diseases in this region. The current systematic review and meta-analysis performs a comprehensive synthesis of the available knowledge, providing an evidence-based overview of the ectoparasites detected on rodents in Middle Eastern countries. Following a systematic search in Pubmed, Scopus, and Web of Science, a total of 113 published articles on rodent ectoparasites were studied and analyzed. A total of 87 rodent species were documented, from which Mus musculus, Rattus norvegicus, and Rattus rattus were found to be the most common. Fleas were the most reported ectoparasites (87 articles), followed by mites (53), ticks (44), and lice (25). Xenopsylla cheopis, Polyplax spinulosa, Ornithonyssus bacoti, and Hyalomma rhipicephaloides were the most commonly described fleas, lice, mites, and ticks, respectively. Based on the reviewed articles, the median flea, louse, mite, and tick indices were highest in Israel (4.15), Egypt (1.39), Egypt (1.27), and Saudi Arabia (1.17), respectively. Quantitative meta-analysis, using a random-effects model, determined the overall pooled flea prevalence in the Middle East as 40% (95% CI: 25–55, I² = 100%, p < 0.00001), ranging between 13% (95% CI: 0–30, I² = 95%, p < 0.00001) in Iran and 59% (95% CI: 42–77, I² = 75%, p < 0.00001) in Israel. The overall pooled louse prevalence was found to be 30% (95% CI: 13–47, I² = 100%, p < 0.00001), ranging between 25% in Iran (95% CI: 1–50, I² = 99%) and 38% in Egypt (95% CI: 7–68, I² = 100%). In the case of mites, the pooled prevalence in this region was 33% (95% CI: 11–55, I² = 100%, p < 0.00001), where the country-specific prevalence estimates were 30% in Iran (95% CI: 4–56, I² = 99%) and 32% in Egypt (95% CI: 0–76, I² = 100%). For ticks, the overall prevalence was found to be 25% (95% CI: 2–47, I² = 100%, p < 0.00001), ranging from 16% in Iran (95% CI: 7–25, I² = 74%) to 42% in Egypt (95% CI: 1–85, I² = 100%). The control of rodent ectoparasites should be considered to reduce their adverse effects. Using the One Health strategy, rodent control, and precisely control of the most common rodent species, i.e., Mus musculus, Rattus norvegicus, and Rattus rattus, should be considered to control the rodent-borne ectoparasites in this region.