Detection and molecular identification of Blastocystis isolates from humans and cattle in northern Egypt

Molecular detection and characterization of Blastocystis in herbivore livestock species in Portugal

Blastocystis is a ubiquitous intestinal protist in humans and animals worldwide. The traditional livestock free-roaming raising system in rural communities increases the risk of infection with contact with a wider range of pathogens transmitted via the faecal-oral route associated with that wildlife-livestock-human interface. However, no studies have been conducted to determine the occurrence and subtype distribution of Blastocystis in livestock in Portugal. Here, we collected 180 faecal samples from herbivore livestock (cattle, goats, horses, and sheep) in different regions of the country to investigate Blastocystis prevalence and subtype diversity using PCR and next-generation amplicon sequencing. Blastocystis was present in 40.6% (73/180; 95% CI: 33.31-48.11) of the samples (goats, 81.0%; sheep, 60.9%; cattle, 32.2%). None of the horse samples were Blastocystis-positive. Eighteen subtypes were detected (ST1-ST3, ST5-ST7, ST10, ST13, ST14, ST21, ST23-ST26, ST30, ST42-ST44). Mixed infections were detected in 97.3% of the Blastocystis-positive samples. Potentially zoonotic subtypes were identified in 75.0%, 96.4%, and 100% of the Blastocystis-positive specimens collected from cattle, sheep, and goats, respectively. These results demonstrate that cattle, sheep, and goats harbour a high diversity of Blastocystis subtypes in the study regions. Importantly, our data provide novel molecular evidence strongly suggesting that some Blastocystis STs/ST subgroups may have differential host specificity.

Molecular Epidemiology and Genetic Diversity of the Enteric Protozoan Parasite Blastocystis sp. in the Northern Egypt Population

Blastocystis sp. is currently reported as the most frequent single-celled eukaryote inhabiting the intestinal tract of humans and a wide range of animal groups. Its prevalence is especially higher in developing countries linked with fecal peril. Despite a growing interest in this enteric protozoan, certain geographical regions potentially at high risk of infection, such as North Africa, remain under-investigated. Therefore, a large-scale molecular epidemiological survey, including 825 participants presenting digestive disorders or not, was conducted in five governorates located in Northern Egypt. A real-time polymerase chain reaction (qPCR) assay was performed to identify the parasite in stool samples, followed by direct sequencing of the positive PCR products for subtyping and genotyping of the corresponding isolates. The overall prevalence was shown to reach 72.4% in the Egyptian cohort, coupled with a variable frequency depending on the governorate (41.3 to 100%). Among the 597 positive participants, a large proportion of them (39.4%) presented mixed infections, as determined by sequencing. The remaining individuals with single infection were predominantly colonized by subtype 3 (ST3) (48.3%) followed by ST1 (39.5%), ST2 (10.8%), ST14 (1.1%), and ST10 (0.3%). This was the first report of ST10 and ST14 in North Africa. Age, sex, digestive symptoms, and health status of the participants or contact with animals were not identified as significant risk factors for Blastocystis sp. occurrence or affecting the ST distribution. In contrast, substantial variations in the prevalence and ST distribution of the parasite were reported according to the governorate. Genotyping of isolates revealed the lower intra-ST diversity for ST3, followed by ST1 and then ST2. By combining subtyping and genotyping data, a widespread inter-human transmission was strongly suggested for ST3 within the Egyptian cohort. Regarding ST1 and ST2, additional animal or environmental sources of infection by these STs have been proposed, whereas the few cases of colonization by ST10 and ST14 were likely the result of zoonotic transmission from bovid. These investigations clearly emphasized the active circulation of Blastocystis sp. in Northern Egypt and the necessity for health authorities to implement prevention campaigns towards the population and quality control of drinking water, with the aim of reducing the burden of this enteric protozoan in this endemic country.

Occurrence and Phylogenetic Analysis of Zoonotic Enteropathogenic Protist Parasites in Asymptomatic Domestic Ruminants from Portugal

Enteropathogenic parasites are of significant concern for public health due to their zoonotic potential and their impact on human and animal health. In this study, we investigated their occurrence and characterized these enteropathogens in asymptomatic domestic ruminants from Portugal. A total of 302 stool samples were collected from cattle (n = 166), sheep (n = 73), and goats (n = 63) in various regions of Portugal and tested for Cryptosporidium spp., Giardia duodenalis, Enterocytozoon bieneusi, Blastocystis sp., and Balantioides coli by PCR. The occurrence of Cryptosporidium spp. was found to be 12.7% (8/63, 95% confidence interval [CI]: 5.65-23.5) in goats; however, no sample was found to be positive for Cryptosporidium spp. in cattle and sheep. For E. bieneusi, 6.35% (4/63; 95%CI: 1.76-15.47) of goats were found to be positive; however, no cattle or sheep were found to be positive. Blastocystis sp. was found in sheep (9.59%; 7/73; 95% [CI]: 0.394-18.76) and goats (12.70%; 8/63; 95% [CI]: 5.65-23.50) but none was found in cattle. No positive results for G. duodenalis or B. coli were detected in this study. This study provides essential baseline information for understanding the silent shedding and epidemiology of these enteropathogens in Portugal, contributing to overall livestock health and related occupational safety. Raising awareness among consumers, veterinarians, and farm owners is crucial to minimize the risk of transmission and promote effective disease control strategies.

Efficacy of Nitazoxanide, Nitazoxanide-Garlic Combination and Tinidazole in Treatment of Giardia duodenalis and Blastocystis hominis: Coproscopic Assessment

Background

Giardia duodenalis and Blastocystis hominis are among the most common intestinal protozoa worldwide. Treatment of infection by metronidazole (MTZ) has some limitations. The objective of this study was to detect the prevalence of Blastocystis and giardiasis among school-age children from December 2021 till March 2022 from Motoubes, Kafrelsheikh, Egypt, and determine the efficacy of nitazoxanide (NTZ), NTZ plus garlic and tinidazole (TIN) on Blastocystis and giardiasis infection.

Methods

Stool samples were collected from 390 children and microscopically examined using formalin-ethyl acetate concentration and culturing on Jones' medium for B. hominis. Those who tested positive for giardiasis (120 children, 30.7%) (Group I) or Blastocystis (180 children, 46.1%) (Group II) were equally divided into four subgroups. The first subgroup received NTZ orally, every 12 hours for three successive days. The second subgroup received NTZ in the same dose as the first subgroup plus dry garlic powder every 12 hours for three successive days. The third subgroup received TIN as a single oral dose, and a fourth control subgroup. Successful cure was considered if no Blastocystis or giardiasis stages were found in post-treatment faecal specimens.

Results

Cure rate was significantly higher in TIN treated groups (75.5% and 96.6%) than NTZ (57.7% and 40%) or NTZ plus garlic treated groups (55.5% and 43%) in both Blastocystis and giardiasis, respectively (P<0.05).

Conclusion

TIN, once, is more efficacious than NTZ or NTZ plus garlic in the treatment of Blastocystis and giardiasis in children.

Identification and genetic characterization of Blastocystis subtypes in Père David's deer (Elaphurus davidianus) from Shishou, China

Blastocystis is a protozoan parasite frequently reported in the gastrointestinal tract of humans and animals, with a global distribution. No information on the infections of Blastocystis in Père David's deer (Elaphurus davidianus, PDD) is available. In this study, a total of 128 fecal samples collected in the National Nature Reserve of Shishou, Hubei Province of China, were used to determine the occurrence and subtypes of Blastocystis in PDD. Amplification of the SSU rDNA gene confirmed the common presence of Blastocystis infection, with an observed prevalence of 56.3% (72/128). Through nucleotide sequencing and phylogenetic analysis, five known subtypes, which consisted of one zoonotic subtype (ST10) and four ruminant-specifical subtypes (ST21, ST23, ST25, and ST26), were identified in this study. This represents a high degree genetic diversity of parasites within the host. Of the 72 PCR-positive samples, ruminant-specific subtypes were the most frequently observed, with ST21 being the most prevalent subtype (56.9.7%, 41/72). This is the first report characterizing the molecular subtypes of Blastocystis in PDD. The findings demonstrate a broad diversity and zoonotic potential of Blastocystis in PDD. Further study of the transmission potential between wildlife and humans or domestic animals in the region is required.

Prevalence, Subtype Distribution and Zoonotic Significance of Blastocystis sp. Isolates from Poultry, Cattle and Pets in Northern Egypt

Blastocystis sp. is a widespread enteric protozoan that frequently infects human and animal groups. Despite its burden and zoonotic potential worldwide, epidemiological investigations remain limited in animal groups that come in contact with humans. Therefore, the largest survey ever conducted in North Africa was performed in Egypt with the aim to investigate the prevalence and subtype (ST) distribution of Blastocystis sp. in animals. For this purpose, a total of 889 fecal specimens were collected from chickens (217), cattle (373), dogs (144) and cats (155) from six governorates of northern Egypt. These specimens were then screened for the presence of Blastocystis sp. using a quantitative real-time PCR, followed by subtyping the isolates. The overall prevalence of Blastocystis sp. reached 9.2% (82/889), with the highest infection rates reported in chickens (17.0%) and domestic cattle (11.0%), highlighting an active circulation of the parasite in both animal groups. In contrast, the low prevalence in cats (2.6%) and the absence of the parasite in dogs suggested that pets are not natural hosts of Blastocystis sp. ST10 and ST14 were largely predominant in cattle, confirming that both STs represented cattle-adapted STs. The report of one ST3 and one ST4 isolate in this animal group could be explained by an accidental zoonosis from humans to animals. All but one of the subtyped isolates in poultry belonged to ST7, which was considered as an avian ST. The presence of a remaining isolate of ST14 likely reflected a transient infection from contact between birds and cattle feces. The same environmental contamination was also likely the source of the ST14 infection in three of the four positive cats, with the remaining animals infected by ST3 as the result of human-to-animal transmission. These occurrences and subtyping data, combined with those previously collected in the Egyptian population, implies that poultry could play a significant role as reservoir for zoonotic transmission, which would not be the case for cattle and pets.

Subtypes and phylogenetic analysis of Blastocystis sp. isolates from West Ismailia, Egypt

In Egypt, Blastocystis sp. is not yet on the diagnostic list of parasitology reports, and information about its subtypes (STs) is scarce. This study investigated its prevalence and its STs/alleles, performed phylogenetic analysis, and considered the distribution of risk factors associated with Blastocystis sp. infections in West Ismailia, Ismailia governorate. Sociodemographic data, exposure factors, and previous parasitic infection status were recorded for symptomatic and asymptomatic individuals. Microscopy, polymerase chain reaction, sequencing, and phylogenetic analysis for Blastocystis sp. isolated from fecal samples were performed. Eighty Blastocystis sp.-infected individuals (15.3%) were examined. The age of the individuals ranged between 0.60 and 85.0 (mean 17.10 ± 15.70), the male/female ratio was 33/47, and the asymptomatic/symptomatic ratio was 55/25. The findings demonstrate clear evidence of direct contact with animals, poor water quality, and previous parasitic infections. Eleven samples yielded three Blastocystis STs (ST1: allele 4, ST2: alleles 9 and 12, and ST3: allele 34), with ST3 (45.5%) representing the most common subtype. Phylogenetic analysis with a robust bootstrap revealed three distinct clades for isolates of each subtype. This study updates the epidemiological knowledge of the distribution of Blastocystis sp. STs in Egypt and expands the current understanding of the prevalence, risk factor frequencies, and genetic diversity of this protist in the studied area.

P entatrichomonas hominis and other intestinal parasites in school-aged children: coproscopic survey

Pentatrichomonas hominis (P. hominis) is a large intestinal flagellated protozoan infecting humans. Little is known about the epidemiology of P.hominis in Egypt, its association with gastrointestinal symptoms and the co-infection with other parasites. Demographic and clinical data were collected from 180 school-aged children. Parasitological examination of fecal samples was done using direct wet mount, formalin ethyl-acetate, Kato-Katz and cultivation on Jones' medium to detect P. hominis and associated parasitic infection. The diagnosis of P. hominis was confirmed using Giemsa stain and scanning electron microscopy. The prevalence of P. hominis was 13.8% (25 out of 180 children). The prevalence of parasitic co-infection was significantly higher in P. hominis infected (84%, 21 participants) than in non-infected children (56%, 87 participants). The presence of abdominal pain and diarrhea in P. hominis infected children was higher than in non-infected children (84% and 32% vs. 76% and 18%), respectively. The difference was not statistically significant. This is the first report of P. hominis in Egypt. The significant association between P. hominis and other intestinal parasites need more investigations. Further studies are needed to understand the epidemiology and pathogenicity of P. hominis.

Detection, Molecular Identification and Transmission of the Intestinal Protozoa Blastocystis sp. in Guinea from a Large-Scale Epidemiological Study Conducted in the Conakry Area

Blastocystis sp. is a single-celled parasite estimated to colonize the digestive tract of 1 to 2 billion people worldwide. Although it represents the most frequent intestinal protozoa in human stools, it remains still under-investigated in countries with a high risk of infection due to poor sanitary and hygiene conditions, such as in Africa. Therefore, the present study was carried out to determine the prevalence and subtype (ST) distribution of Blastocystis sp. in the Guinean population. For this purpose, fecal samples were collected from 500 individuals presenting or not digestive disorders in two hospitals of Conakry. Search for the parasite in stools was performed by real-time PCR targeting the small subunit rDNA gene followed by sequencing of the PCR products for subtyping of the isolates. A total of 390 participants (78.0%) was positive for Blastocystis sp. Five STs were identified in the Guinean cohort (ST1, ST2, ST3, ST4 and ST14) with varying frequency, ST3 being predominant. Among them, ST4 was found in only two patients confirming its global rarity in Africa whereas infections by ST14 were likely the result of zoonotic transmission from bovid. No significant association was detected between Blastocystis sp. colonization or ST distribution and the symptomatic status of Guinean subjects or the presence of digestive symptoms. In contrast, drilling water consumption represented a significant risk factor for infection by Blastocystis sp. Predominance of ST3 coupled with its low intra-ST diversity strongly suggested large-scale human-to-human transmission of this ST within this cohort. In parallel, the highest intra-ST diversity of ST1 and ST2 was likely correlated with various potential sources of infection in addition to anthroponotic transmission. These findings highlighted the active circulation of the parasite in Guinea as reported in some low-income African countries and the necessity to implement prevention and control measures in order to limit the circulation of this parasite in this endemic geographical area.