Blastocystis sp. in Small Ruminants: A Universal Systematic Review and Meta-analysis

• Published in: Acta parasitologica Vol. 67; no. 3; pp. 1073 - 1085
• Main Authors: Shams, Morteza, Asghari, Ali, Baniasad, Maryam, Shamsi, Laya, Sadrebazzaz, Alireza
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-09-2022; Springer Nature B.V
• Subjects: Animal Systematics/Taxonomy/Biogeography; Biomedical and Life Sciences; Biomedicine; Blastocystis; Datasets; Ecology; Epidemiology; Goats; Medical Microbiology; Meta-analysis; Microbiology; Parasitology; Review; Search engines; Sheep; Subtypes; Animals; sp; Meta-analysis
• ISSN: 1230-2821; 1896-1851
• DOI: 10.1007/s11686-022-00589-3

Purpose
The present review was done to evaluate the prevalence and subtype distribution of
Blastocystis
infection among small ruminants, at a global perspective.
Methods
Systematic search was performed in PubMed, Scopus, Google Scholar, and Web of Science until 30th January 2022 and total estimates along with 95% confidence intervals (CIs) were computed using a random-effects model.
Results
Ultimately, the required data were extracted from 25 papers including 19 datasets for each animal. Among 3125 sheep, the
Blastocystis
prevalence was 25.3% (95% CI 16.1–37.4%) (10 countries), being lower in comparison to that in 2869 examined goats [20.5% (95% CI 11–35.1%)] (12 countries). Regarding STs distribution, fourteen genetically diverse STs of
Blastocystis
(ST1-ST5, ST7, ST10, ST12, ST14, ST15, ST21, ST23, ST24, ST26) have been reported in sheep, and the highest pooled prevalence was related to ST10 [11 datasets, 57.8% (95% CI 43.7–70.8%)], followed by ST14 [8 datasets, 28.4% (95% CI 20.2–38.4%)], and ST7 [2 datasets, 21.1% (95% CI 4.5–60.3%)]. Compared to sheep, more STs (ST1, ST3-ST7, ST10, ST12, ST14, ST21, ST23-ST26, and ST32) were reported from goats, and the highest weighted frequency was related to ST10 [6 datasets, 45.1% (95% CI: 25.6–66.2%)], followed by ST7 [2 datasets, 40.4% (95% CI 30–51.7%)], and ST14 [4 datasets, 29% (95% CI 15.5–47.7%)]. Out of ten known zoonotic STs reported for
Blastocystis
(ST1-ST9, and ST12), 7 were isolated from sheep (ST1-ST5, ST7, and ST12) and 7 were reported from goats (ST1, ST3-ST7, ST12).
Conclusions
Overall,
Blastocystis
epidemiology in sheep and goats is yet to be elucidated and demands more comprehensive studies.