Abstract
Background
The present systematic review and meta‐analysis aimed to gather and analyse global data on the prevalence, subtypes (STs) distribution and zoonotic potential of Blastocystis sp. in rodents.
Methods
A systematic literature search was performed across multiple databases (PubMed, Scopus, Web of Science and ProQuest) for studies published by 23 July 2024. The analysis included 34 studies/78 datasets, comprising 5661 samples from various rodent species across 15 countries. Statistical analyses were performed using comprehensive meta‐analysis (CMA) software, employing a random‐effects model to estimate pooled prevalence and 95% confidence intervals (CIs) and the I 2 index for assessing heterogeneity.
Results
This review found that 16% (95% CI: 12.6%–20.2%) of rodents worldwide were infected with Blastocystis sp. Voles and squirrels exhibited the highest infection rates at 29.8% (95% CI: 14.7%–51%) and 28.8% (95% CI: 14.4%–49.2%), whereas civets and porcupines had the lowest rates at 9.5% (95% CI: 6.6%–13.6%) and 7.1% (95% CI: 3.3%–14.7%), respectively. The findings indicated that rodents can host various Blastocystis sp. STs (ST1–ST8, ST10, ST13, ST15, ST17), with several (ST1–ST8 and ST10) having zoonotic potential. Globally, ST4, ST5, ST1 and ST3 were the most commonly reported STs in rodents. China and the UK showed the highest ST diversity in rodents, with 10 (ST1‐ST7, ST10, ST13, ST17) and 7 (ST1‐ST5, ST10, ST15) distinct STs, respectively. ST6, ST7 and ST13 were unique to China, whereas ST15 was found only in the United Kingdom. Squirrels, rats, mice and voles had the highest ST diversity of Blastocystis sp., with 8, 7, 5 and 5 distinct STs, respectively. Notably, ST6 and ST13 were unique to squirrels, ST7 only appeared in rats, and ST15 was found only in voles. Most ST1, ST3–ST5 and ST17 came from Asia. ST6, ST7 and ST13 were also isolated there, whereas ST15 was only found in Europe. ST17 was reported in Africa, ST4 and ST17 in North America, and ST1–ST3 and ST8 in South America.
Conclusions
This review emphasizes the widespread presence of Blastocystis sp. in rodent populations globally, underscoring the need for continued surveillance and research into its zoonotic potential.
Keywords: Blastocystis sp, epidemiology, meta‐analysis, rodents, subtypes, systematic review
Overall, 16% of rodents worldwide were infected with Blastocystis sp. (95% CI: 12.6%–20.2%). Rodents host various Blastocystis sp. subtypes (STs), including ST1‐ST8, ST10, ST13, ST15 and ST17. The most commonly reported STs in rodents globally were ST4, ST5, ST1 and ST3.
1. Introduction
Blastocystis sp. is an anaerobic eukaryotic protist, the only stramenopile known to infect humans (Stensvold and Clark 2016). Over 1 billion people are infected globally, making it likely the most common intestinal parasite (Scanlan and Stensvold 2013). This protist is primarily transmitted through the faecal–oral route, either by direct contact with infected hosts or by consuming contaminated food or water (Tan 2004).
The presence of Blastocystis sp. in various pets, livestock and wildlife indicates that these reservoir species play a key role in transmitting the parasite to humans and vice versa (Hublin, Maloney, and Santin 2021). Blastocystis sp. displays significant genetic diversity, with 44 recognized subtypes (STs) (Koehler et al. 2024; Šejnohová et al. 2024). Of these, only 16 are zoonotic (ST1–ST10, ST12, ST14, ST16, ST23, ST35 and ST41) and have been found in humans, with ST1–ST4 representing over 95% of reported cases (Maloney et al. 2022; Hernández et al. 2023).
Previous findings revealed that certain Blastocystis sp. STs, such as ST4, positively affect intestinal commensal bacteria and inhibit pathogenic growth, indicating a potential role in gut health. Additionally, Blastocystis sp. colonization may beneficially alter the gut bacterial composition, enhance short‐chain fatty acid (SCFA) production, and influence immune responses (Th2 and Treg) in various murine models. ST1, another common human subtype, also demonstrated positive effects on gut microbiota and adaptive immune responses, further supporting the notion that some Blastocystis sp. STs may promote health. Although evidence supports that Blastocystis sp. is primarily a commensal organism, exceptions exist, notably ST7, which exhibits pathogenic potential. Both in vitro and rodent studies indicated that ST4 can cause mild inflammation, highlighting caution in universally classifying Blastocystis sp. as commensal, given the genetic diversity among STs. Future research should explore the mechanisms of Blastocystis sp. interactions with gut microbiota and their effects on microbial‐derived metabolites like SCFAs and bile acids. Additionally, further studies in humans or naturally colonized animals are needed to clarify the role of Blastocystis sp. in immunity and gut health (Deng et al. 2021; Deng and Tan 2022; Deng et al. 2022, 2023).
Rodents play a crucial role in every terrestrial ecosystem. With nearly 36 families and 2552 species, they are the most diverse and representative group, comprising 40% of all mammals (Islam 2021). Outbreaks of rodent‐borne zoonotic diseases, such as bubonic plague, leishmaniasis and typhus, have occurred worldwide (Rabiee et al. 2018; Ganjeer et al. 2021). Moreover, some animals, such as cats and dogs, can consume rodents, facilitating human infections and transmission of parasites like Blastocystis sp. between species (Morelli et al. 2021; Macpherson et al. 2022). These cases underscore the urgent need for a comprehensive framework to study infections like Blastocystis sp. in rodent populations. Hence, this review aimed to statistically analyse and summarize the prevalence and ST distribution of Blastocystis sp. in rodents, given the potential pathogenicity and zoonotic nature of some Blastocystis sp. STs.
2. Materials and Methods
2.1. Ethical Approval
The present study with the code IR.QUMS.REC.1403.231 was approved by the ethics committee of Qazvin University of Medical Sciences, Qazvin, Iran.
2.2. Type and Design of the Study
The current study was a systematic review and meta‐analysis conducted during 2024. The studies were reported according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta‐Analysis) checklist guidelines (Moher et al. 2015).
2.3. Search Strategy
Four key global databases (Medline/PubMed, ProQuest, Scopus and the Web of Knowledge) were searched for articles published up to 23 July 2024. Google Scholar and the references of included articles were also probed to identify any overlooked studies. The search utilized Medical Subject Headings (MeSH) terms alone or in combination: (‘Intestinal Parasites’ OR ‘Parasitic Infections’ OR ‘Blastocystis sp.’) AND (‘Prevalence’ OR ‘Epidemiology’ OR ‘Frequency’ OR ‘Occurrence’) AND (‘Subtype’ OR ‘Subtyping’) AND (Rodents). The collected data were imported into Endnote X9, where duplicates were automatically removed, and the remaining studies were evaluated by two researchers on the basis of their titles and abstracts.
2.4. Inclusion and Exclusion Criteria
This study included all published descriptive cross‐sectional studies with accessible full texts on the prevalence and distribution of Blastocystis sp. STs in rodents, without restrictions on time, language, or geography. Excluded were review studies, case studies, commentaries, human studies, studies involving animals other than rodents, experimental studies, studies/datasets conducted based on one sample and those with unclear or ambiguous results and sample sizes.
2.5. Quality Evaluation Checklist
In addition to the inclusion and exclusion criteria, the studies were evaluated using the Joanna Briggs Institute (JBI) checklist (Munn et al. 2014), which consists of nine questions/parts regarding sample size, statistical analysis, sample explanations, confounding factors and subgroup analysis. Each study was rated with a yes/no response. Studies scoring 4–6 and ≥7 were classified as medium and high quality, respectively, whereas those scoring ≤3 were excluded from the review.
2.6. Meta‐Analysis
Statistical analyses were conducted using comprehensive meta‐analysis (CMA) v3 software, with p values below 0.05 considered statistically significant (Mahdavi et al. 2024). A random‐effects model was used to assess the prevalence of Blastocystis sp. in rodents, providing pooled prevalence and 95% confidence intervals (CIs). A subgroup analysis assessed the weighted prevalence of rodent infections by WHO regions, countries, publication years, continents and sample sizes. A forest plot illustrated the pooled prevalence and 95% CIs, whereas a funnel plot evaluated publication bias. Heterogeneity among studies was assessed using the I 2 index, with values categorized as low (below 25%), moderate (25%–50%) and high (above 50%). Additionally, a sensitivity analysis was performed to evaluate the impact of excluding specific studies on the final weighted prevalence of Blastocystis sp.
3. Results
3.1. Selection of Studies
Expert researchers thoroughly searched four international databases, identifying 7251 initial records. After removing duplicates and reviewing the 5643 remaining studies, they ultimately selected 36 articles. Finally, a quality assessment using JBI criteria excluded two additional studies, resulting in 34 relevant studies (78 datasets) (Alfellani et al. 2013; Ramírez et al. 2014; Seifollahi et al. 2016; Yoshikawa et al. 2016; Cian et al. 2017; Mohaghegh et al. 2018; Wang et al. 2018, 2024; Betts et al. 2018, Betts, Gentekaki, and Tsaousis 2020; AbuOdeh et al. 2019; Valenca‐Barbosa et al. 2019; Xiao et al. 2019; Li et al. 2020; Martinez‐Hernandez et al. 2020; Mohammadpour et al. 2020; Oliveira‐Arbex et al. 2020; Li et al. 2020; Chai et al. 2020; Liu et al. 2021, 2022, 2024; Malatyalı et al. 2021; Masuda et al. 2021; Rudzińska et al. 2021; Song et al. 2021; Chen et al. 2021; Deng et al. 2021; Tantrawatpan et al. 2023; Zhao et al. 2023; Martínez‐Hernández et al. 2024; Bastaminejad et al. 2024; Shan et al. 2024; Gao et al. 2024) meeting the inclusion criteria for this study (Figure 1). Of note, the search, conducted without an initial time limit, continued until 23 July 2024, including any articles that met the study criteria. The included studies began in 2013 (Table 1), indicating that no relevant studies existed before that year.
FIGURE 1.
Flowchart depicting the process of included studies in the present review.
TABLE 1.
Key information from 34 articles/78 datasets on the occurrence and subtypes (ST) distribution of Blastocystis sp. in rodents.
| Author (year) | Host (scientific name) | Host species | Time tested | Country | Total no. | Infected no. | Prevalence (%) | Method | STs d |
|---|---|---|---|---|---|---|---|---|---|
| Alfellani et al. (2013) | Bank vole (Clethrionomys glareolus) | Voles | UC a | Poland | 6 | 0 | 0 | MOL b | — |
| Alfellani et al. (2013) | Bank vole (Clethrionomys glareolus) | Voles | UC | The United Kingdom | 32 | 1 | 3.1 | MOL | ST5 (1) |
| Alfellani et al. (2013) | Chinchilla (Chinchilla lanigera) | Chinchillas | UC | Belgium | 5 | 2 | 40 | MOL | ST3 (2) |
| Alfellani et al. (2013) | Wood mouse (Apodemus sylvaticus) | Mice | UC | The United Kingdom | 13 | 1 | 7.7 | MOL | ST3 (1) |
| Alfellani et al. (2013) | Gundi (Ctenodactylus gundi) | Gundis | UC | Libya | 4 | 1 | 25 | MOL | ST17 (1) |
| Ramírez et al. (2014) | Black rat (Rattus rattus) | Rats | UC | Colombia | 10 | 3 | 30 | MOL | ST2 (3) |
| Seifollahi et al. (2016) | Rodent spp. | Rodent spp. | UC | Iran | 52 | 10 | 19.2 | MIC c | ND (10) |
| Yoshikawa et al. (2016) | Rodent spp. | Rodent spp. | 2010–2012 | Indonesia | 77 | 10 | 13 | MOL | ST4 (9), ND e (1) |
| Cian et al. (2017) | Brown rat (Rattus norvegicus) | Rats | 2014–2015 | France | 2 | 1 | 50 | MOL | ST4 (1) |
| Cian et al. (2017) | Capybara (Hydrochoerys hydrochaeris) | Capybaras | 2014–2015 | France | 5 | 3 | 60 | MOL | ST2 (1), ST5 (1), ND (1) |
| Cian et al. (2017) | House mouse (Mus musculus) | Mice | 2014–2015 | France | 2 | 0 | 0 | MOL | — |
| Cian et al. (2017) | Indian crested porcupine (Hystrix indica) | Porcupines | 2014–2015 | France | 2 | 0 | 0 | MOL | — |
| Cian et al. (2017) | Patagonian mara (Dolichotis patagonum) | Patagonian mara | 2014–2015 | France | 3 | 0 | 0 | MOL | — |
| Betts et al. (2018) | Red squirrel (Sciurus vulgaris) | Squirrels | 2016–2017 | The United Kingdom | 3 | 2 | 66.7 | MOL | ST4 (1), ND (1) |
| Betts et al. (2018) | Water Vole (Arvicola amphibius) | Voles | 2016–2017 | The United Kingdom | 11 | 10 | 90.9 | MOL | ST1 (1), ST4 (36), ST10 (1) |
| Mohaghegh et al. (2018) | Wistar rat | Rats | UC | Iran | 60 | 33 | 55 | MIC | ND (33) |
| Wang et al. (2018) | Brown rat (Rattus norvegicus) | Rats | 2015–2017 | China | 108 | 4 | 3.7 | MOL | ST4 (4) |
| Xiao et al. (2019) | Flying squirrel (Trogopterus xanthipes) | Squirrels | 2017 | China | 69 | 28 | 30.4 | MOL | ST1 (12), ST3 (7), ST13 (9) |
| AbuOdeh et al. (2019) | Squirrel | Squirrels | UC | The UAE | 6 | 3 | 50 | MOL | ST4 (2), ST17 (1) |
| Valenca‐Barbosa et al. (2019) | Rodent spp. | Rodent spp. | UC | Brazil | 11 | 7 | 63.6 | MOL | ST3 (1), ST8 (1), ND (5) |
| Oliveira‐Arbex et al. (2020) | Capybara (Hydrochoerus hydrochaeris) | Capybaras | UC | Brazil | 23 | 2 | 8.7 | MOL | ST1, ST8 |
| Chai et al. (2020) | Eurasian red squirrel (Sciurus vulgaris) | Squirrels | 2018–2019 | China | 72 | 7 | 9.7 | MOL | ST4 (7) |
| Chai et al. (2020) | Eastern chipmunk (Tamias striatus) | Squirrels | 2018–2019 | China | 171 | 8 | 4.7 | MOL | ST4 (8) |
| Chai et al. (2020) | Chinchilla (Chinchilla lanigera) | Chinchillas | 2018–2019 | China | 72 | 3 | 4.2 | MOL | ST4 (2), ST17 (1) |
| Chai et al. (2020) | Guinea pig (Cavia porcellus) | Guinea pigs | 2018–2019 | China | 90 | 12 | 13.3 | MOL | ST4 (12) |
| Chai et al. (2020) | Chinese striped hamster (Cricetulus barabensis) | Mice | 2018–2019 | China | 98 | 12 | 12.2 | MOL | ST4 (12) |
| Li et al. (2020) | Sprague–Dawley rat | Rats | 2019 | China | 151 | 17 | 11.3 | MOL | ST4 (16), ST7 (1) |
| Li et al. (2020) | Wistar rat | Rats | 2019 | China | 104 | 9 | 8.7 | MOL | ST4 (9) |
| Li et al. (2020) | Spontaneous hypertensive rat | Rats | 2019 | China | 100 | 3 | 3 | MOL | ST4 (1), ST7 (2) |
| Li et al. (2020) | Patagonian mara (Dolichotis patagonum) | Patagonian mara | UC | China | 15 | 3 | 20 | MOL | ST4 (3) |
| Martinez‐Hernandez et al. (2020) | Kangaroo rat (Heteromyidae sp.) | Rats | 2015–2016 | Mexico | 8 | 4 | 50 | MOL | ST4 (1), ST17 (2), ND (1) |
| Martinez‐Hernandez et al. (2020) | Rodent spp. | Rodent spp. | 2015–2016 | Mexico | 22 | 0 | 0 | MOL | — |
| Betts, Gentekaki, and Tsaousis (2020) | Red squirrel (Sciurus vulgaris) | Squirrels | 2016–2019 | The United Kingdom | 5 | 3 | 60 | MOL | ST2 (3), ST4 (1) |
| Betts, Gentekaki, and Tsaousis (2020) | Water vole (Arvicola amphibius) | Voles | 2016–2019 | The United Kingdom | 74 | 27 | 36.5 | MOL | ST1 (3), ST4 (78), ST10 (1), ST15 (3), ND (2) |
| Mohammadpour et al. (2020) | Brown rat (Rattus norvegicus) | Rats | 2016–2018 | Iran | 127 | 20 | 15.8 | MOL | ST1 (4), ST3 (4), ST4 (12) |
| Rudzińska et al. (2021) | Capybara (Hydrochoerus hydrochaeris) | Capybaras | 2018–2019 | Poland | 6 | 0 | 0 | MOL | — |
| Liu et al. (2021) | Pallas's squirrel (Callosciurus erythraeus) | Squirrels | 2018 | China | 171 | 10 | 5.8 | MOL | ST1 (1), ST3 (1), ST5 (4), ST6 (4) |
| Masuda et al. (2021) | Pallas's squirrel (Callosciurus erythraeus) | Squirrels | UC | Japan | 423 | 186 | 44 | MOL | ST4 (85), ND (101) |
| Chen et al. (2021) | Porcupine (Hystrix hodgsoni) | Porcupines | 2020 | China | 7 | 1 | 14.3 | MOL | ST1 (1) |
| Song et al. (2021) | Bamboo rat (Rhizomys sinensis) | Rats | UC | China | 480 | 22 | 4.6 | MOL | ST4 (17), ST5 (5) |
| Malatyalı et al. (2021) | Laboratory rat (Sprague–Dawley rats) | Rats | UC | Turkey | 54 | 33 | 61.1 | MOL | ST4 (33) |
| Deng et al. (2021) | Rodent spp. | Rodent spp. | 2017–2019 | China | 33 | 6 | 18.2 | MOL | ST4 (2), ST17 (4) |
| Liu et al. (2022) | Coypu (Myocastor coypus) | Coypus | 2018–2019 | China | 308 | 44 | 14.3 | MOL | ST4 (33), ST5 (3), ND (8) |
| Tantrawatpan et al. (2023) | Capybara (Hydrochoerus hydrochaeris) | Capybaras | UC | Thailand | 3 | 0 | 0 | MOL | — |
| Tantrawatpan et al. (2023) | Guinea pig (Cavia porcellus Anas) | Guinea pigs | UC | Thailand | 12 | 0 | 0 | MOL | — |
| Tantrawatpan et al. (2023) | Malayan porcupine (Hystrix brachyura) | Porcupines | UC | Thailand | 5 | 1 | 20 | MOL | ST8 (1) |
| Tantrawatpan et al. (2023) | Rice field rat (Rattus argentiventer) | Rats | UC | Thailand | 10 | 1 | 10 | MOL | ST4 (1) |
| Tantrawatpan et al. (2023) | Pllas's squirrel (Callosciurus erythraeus) | Squirrels | UC | Thailand | 10 | 6 | 60 | MOL | ST4 (4), ND (2) |
| Tantrawatpan et al. (2023) | Variable squirrel (Callosciurus finlaysonii) | Squirrels | UC | Thailand | 2 | 1 | 50 | MOL | ST4 (1) |
| Zhao et al. (2023) | Asiatic brush‐tailed porcupine (Atherurus macrourus) | Porcupines | 2017–2021 | China | 257 | 12 | 4.7 | MOL | ST4(11), ND (1) |
| Zhao et al. (2023) | Bamboo rat (Rhizomys pruinosus) | Rats | 2017–2021 | China | 360 | 8 | 2.2 | MOL | ST4 (8) |
| Zhao et al. (2023) | Masked palm civet (Paguma larvata) | Civets | 2017–2021 | China | 283 | 27 | 9.5 | MOL | ST1 (1), ST5 (26) |
| Liu et al. (2024) | Brown rat (Rattus norvegicus) | Rats | 2023–2024 | China | 195 | 63 | 32.3 | MOL | ST1 (4), ST2 (2), ST4 (57) |
| Liu et al. (2024) | House mouse (Mus musculus) | Mice | 2023–2024 | China | 106 | 16 | 15.1 | MOL | ST4 (16) |
| Liu et al. (2024) | Striped field mouse (Apodemus agrarius) | Mice | 2023–2024 | China | 89 | 18 | 20.2 | MOL | ST4 (17), ST10 (1) |
| Liu et al. (2024) | Striped hamster (Cricetulus barabensis) | Mice | 2023–2024 | China | 96 | 36 | 37.5 | MOL | ST3 (4), ST4 (32) |
| Shan et al. (2024) | Asian house rat (Rattus tanezumi) | Rats | 2021–2023 | China | 136 | 41 | 30.1 | MOL | ST1 (2), ST3 (2), ST4 (8), ST5 (29) |
| Shan et al. (2024) | Brown rat (Rattus norvegicus) | Rats | 2021–2023 | China | 58 | 42 | 72.4 | MOL | ST1 (1), ST2 (1), ST4 (35), ST5 (5) |
| Shan et al. (2024) | House mouse (Mus musculus) | Mice | 2021–2023 | China | 25 | 3 | 12 | MOL | ST3 (1), ST4 (1), ST5 (1) |
| Martínez‐Hernández et al. (2024) | Brown rat (Rattus norvegicus) | Rats | 2020 | Mexico | 52 | 17 | 32.7 | MOL | ND (17) |
| Martínez‐Hernández et al. (2024) | House mouse (Mus musculus) | Mice | 2020 | Mexico | 33 | 4 | 12.1 | MOL | ND (4) |
| Bastaminejad et al. (2024a) | House mouse (Mus musculus) | Mice | 2020 | Iran | 40 | 2 | 5 | MOL | ST1 (1), ND (1) |
| Bastaminejad et al. (2024a) | Brown rat (Rattus norvegicus) | Rats | 2020 | Iran | 40 | 3 | 7.5 | MOL | ST1 (1), ST4 (1), ND (1) |
| Bastaminejad et al. (2024a) | Black rat (Rattus rattus) | Rats | 2020 | Iran | 40 | 3 | 7.5 | MOL | ST4 (2), ND (1) |
| Wang et al. (2024) | Brown rat (Rattus norvegicus) | Rats | 2023 | China | 155 | 4 | 2.6 | MOL | ST4 (4) |
| Wang et al. (2024) | Asian rat (Rattus tanezumi) | Rats | 2023 | China | 86 | 3 | 3.5 | MOL | ST4 (3) |
| Wang et al. (2024) | Chinese white‐bellied rat (Niviventer confucianus) | Rats | 2023 | China | 75 | 13 | 17.3 | MOL | ST1 (1), ST4 (11), ST7 (1) |
| Wang et al. (2024) | Striped field mouse (Apodemus Agrarius Pallas) | Mice | 2023 | China | 36 | 1 | 2.8 | MOL | ST4 (1) |
| Wang et al. (2024) | Lesser ricefield rat (Rattus losea) | Rats | 2023 | China | 18 | 1 | 5.6 | MOL | ST4 (1) |
| Gao et al. (2024) | Buff‐breasted rat (Rattus flavipectus) | Rats | 2023–2024 | China | 39 | 3 | 7.7 | MOL | ST4 (2), ST5 (1) |
| Gao et al. (2024) | Reed vole (Microtus fortis) | Voles | 2023–2024 | China | 139 | 39 | 28.1 | MOL | ST4 (39) |
| Gao et al. (2024) | Brown rat (Rattus norvegicus) | Rats | 2023–2024 | China | 31 | 2 | 6.4 | MOL | ST4 (2) |
| Gao et al. (2024) | Striped field mouse (Apodemus agrarius) | Mice | 2023–2024 | China | 14 | 1 | 7.1 | MOL | ST4 (1) |
| Gao et al. (2024) | Greater bandicoot rat (Bandicota indica) | Rats | 2023–2024 | China | 39 | 1 | 2.5 | MOL | ST4 (1) |
| Gao et al. (2024) | Rattus rattus sladeni | Rats | 2023–2024 | China | 5 | 2 | 40 | MOL | ST4 (2) |
| Gao et al. (2024) | Lesser ricefield rat (Rattus losea) | Rats | 2023–2024 | China | 41 | 6 | 14.6 | MOL | ST4 (6) |
| Gao et al. (2024) | White‐bellied Rat (Niviventer lotipes) | Rats | 2023–2024 | China | 23 | 0 | 0 | MOL | — |
| Gao et al. (2024) | House mouse (Mus musculus) | Mice | 2023–2024 | China | 13 | 0 | 0 | MOL | — |
Unclear.
Molecular detection.
Microscopic detection.
Subtypes.
Not determined.
The higher number of STs compared to positive cases in some studies is due to the presence of the mixed infections with multiple STs and the analysis of multiple samples from a rodent.
3.2. Details of Included Studies
This review included 34 studies/78 datasets, comprising 5661 samples from various rodent species across 15 countries. Our results were based on studies published from 2013 to 2024, with sample sizes ranging from 2 to 480. Belgium, Colombia, Indonesia, Japan, Libya, Turkey and the UAE had only one study/dataset on Blastocystis sp. in rodents, whereas other countries had more than one study/dataset. Of the included studies, only 2 utilized microscopic methods for diagnosing Blastocystis sp., whereas molecular methods accounted for 32 studies/76 datasets. Of the 34 studies, 20 studies/64 datasets reported the distribution of Blastocystis sp. STs (Table 1). The JBI checklist evaluation classified 11 studies as high quality (>6 points) and 23 articles as moderate quality (4–6 points) (Table S1).
3.3. Global Prevalence of Blastocystis sp. in Rodents
The global prevalence of Blastocystis sp. in rodents was estimated at 16% (95% CI: 12.6%–20.2%) (Figure 2), exhibiting significant heterogeneity (Q = 750.1, I 2 = 89.7%, p < 0.001).
FIGURE 2.
The pooled prevalence of Blastocystis sp. in rodents based on data from the included studies, using a random‐effects model and 95% confidence intervals. Orange colours indicate the event rate/prevalence reported in each study, whereas the black colour represents the final weighted prevalence.
3.4. Worldwide Prevalence of Blastocystis sp. in Rodents Based On Species
The weighted prevalence of Blastocystis sp. in rodents based on species is shown in Figure 3. In brief, voles and squirrels exhibited the highest infection rates at 29.8% (95% CI: 14.7%–51%) and 28.8% (95% CI: 14.4%–49.2%), whereas civets and porcupines had the lowest rates at 9.5% (95% CI: 6.6%–13.6%) and 7.1% (95% CI: 3.3%–14.7%), respectively.
FIGURE 3.
The pooled prevalence of Blastocystis sp. in rodents based on different species, using a random‐effects model and 95% confidence intervals.
3.5. ST Distribution of Blastocystis sp. in Rodents
The findings indicated that rodents can host various Blastocystis sp. STs (ST1–ST8, ST10, ST13, ST15, ST17), with several (ST1–ST8 and ST10) having zoonotic potential (Table 1). Globally, ST4, ST5, ST1 and ST3 were the most commonly reported STs in rodents (Table 2).
TABLE 2.
Subtypes (STs) distribution of Blastocystis sp. in rodents by countries and rodent species.
| Variables | Dataset no. | Total samples (no.) | Infected samples (no.) | Reported STs (no.) | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ST1 | ST2 | ST3 | ST4 | ST5 | ST6 | ST7 | ST8 | ST10 | ST13 | ST15 | ST17 | ND b | ||||
| Countries | ||||||||||||||||
| Belgium | 1 | 5 | 2 | — | — | 2 | — | — | — | — | — | — | — | — | — | — |
| Brazil | 2 | 34 | 9 | 1 | — | 1 | — | — | — | — | 2 | — | — | — | — | 5 |
| China | 40 | 4368 | 531 | 23 | 3 | 15 | 384 | 74 | 4 | 4 | — | 1 | 9 | — | 5 | 9 |
| Colombia | 1 | 10 | 3 | — | 3 | — | — | — | — | — | — | — | — | — | — | — |
| France | 5 | 14 | 4 | — | 1 | — | 1 | 1 | — | — | — | — | — | — | — | 1 |
| Indonesia | 1 | 77 | 10 | — | — | — | 9 | — | — | — | — | — | — | — | — | 1 |
| Iran | 6 | 359 | 71 | 6 | — | 4 | 15 | — | — | — | — | — | — | — | — | 46 |
| Japan | 1 | 423 | 186 | — | — | — | 85 | — | — | — | — | — | — | — | — | 101 |
| Libya | 1 | 4 | 1 | — | — | — | — | — | — | — | — | — | — | — | 1 | — |
| Mexico | 4 | 115 | 25 | — | — | — | 1 | — | — | — | — | — | — | — | 2 | 22 |
| Poland | 2 | 12 | 0 | — | — | — | — | — | — | — | — | — | — | — | — | — |
| Thailand | 6 | 42 | 9 | — | — | — | 6 | — | — | — | 1 | — | — | — | — | 2 |
| Turkey | 1 | 54 | 33 | — | — | — | 33 | — | — | — | — | — | — | — | — | — |
| The UAE | 1 | 6 | 3 | — | — | — | 2 | — | — | — | — | — | — | — | 1 | — |
| The United Kingdom | 6 | 138 | 44 | 4 | 3 | 1 | 116 | 1 | — | — | — | 2 | — | 3 | — | 3 |
| Total no. species | 78 | 5661 | 931 | 34 | 10 | 23 | 652 | 76 | 4 | 4 | 3 | 3 | 9 | 3 | 9 | 190 |
| Voles | 5 | 262 | 77 | 4 | — | — | 153 | 1 | — | — | — | 2 | — | 3 | — | 2 |
| Chinchillas | 2 | 77 | 5 | — | — | 2 | 2 | — | — | — | — | — | — | — | 1 | — |
| Mice | 12 | 565 | 94 | 1 | — | 6 | 80 | 1 | — | — | — | 1 | — | — | — | 5 |
| Gundis | 1 | 4 | 1 | — | — | — | — | — | — | — | — | — | — | — | 1 | — |
| Rats | 29 | 2607 | 362 | 13 | 6 | 6 | 238 | 40 | — | 4 | — | — | — | — | 2 | 53 |
| Rodent spp. | 5 | 195 | 33 | — | — | 1 | 11 | — | — | — | 1 | — | — | — | 4 | 16 |
| Capybaras | 4 | 37 | 5 | 1 | 1 | — | — | 1 | — | — | 1 | — | — | — | — | 1 |
| Porcupines | 4 | 271 | 14 | 1 | — | — | 11 | — | — | — | 1 | — | — | — | — | 1 |
| Patagonian mara | 2 | 18 | 3 | — | — | — | 3 | — | — | — | — | — | — | — | — | — |
| Squirrels a | 10 | 932 | 254 | 13 | 3 | 8 | 109 | 4 | 4 | — | — | — | 9 | — | 1 | 104 |
| Guinea pigs | 2 | 102 | 12 | — | — | — | 12 | — | — | — | — | — | — | — | — | — |
| Coypus | 1 | 308 | 44 | — | — | — | 33 | 3 | — | — | — | — | — | — | — | 8 |
| Civets | 1 | 283 | 27 | 1 | — | — | — | 26 | — | — | — | — | — | — | — | — |
| Total no. | 78 | 5661 | 931 | 34 | 10 | 23 | 652 | 76 | 4 | 4 | 3 | 3 | 9 | 3 | 9 | 190 |
A dataset related to chipmunk was included in this group.
Not determined.
The higher number of STs compared to positive cases in some studies is due to the presence of the mixed infections with multiple STs and the analysis of multiple samples from a rodent.
3.6. ST Distribution of Blastocystis sp. in Rodents by Countries, Rodent Species and Continents
The distributions of Blastocystis sp. STs in rodents by countries, species and continents are summarized in Table 2 and Figure 4. In total, STs were reported in 14 countries. The highest numbers of samples were from China (40 datasets, 4368 samples), Japan (1 dataset, 423 samples), Iran (6 datasets, 359 samples), the United Kingdom (6 datasets, 138 samples) and Mexico (4 datasets, 115 samples). China and the United Kingdom exhibited the greatest ST diversity in rodents, with 10 (ST1–ST7, ST10, ST13, ST17) and 7 (ST1–ST5, ST10, ST15) distinct STs reported, respectively. Notably, ST6, ST7 and ST13 were only found in China, whereas ST15 was exclusively reported in the United Kingdom.
FIGURE 4.
ST distribution of Blastocystis sp. in rodents by continents. STs, subtypes.
Species‐based analysis showed that the majority of samples were reported from rats (29 datasets, 2607 samples), squirrels (10 datasets, 932 samples), mice (12 datasets, 565 samples), coypus (1 dataset, 308 samples), civets (1 dataset, 283 samples), porcupines (4 datasets, 271 samples) and voles (5 datasets, 262 samples). Squirrels, rats, mice and voles displayed the highest ST diversity of Blastocystis sp., with 8 (ST1–ST6, ST13 and ST17), 7 (ST1–ST5, ST7 and ST17), 5 (ST1, ST3–ST5 and ST10) and 5 (ST1, ST4, ST5, ST10 and ST15) distinct STs, respectively. Interestingly, ST6 and ST13 were reported solely in squirrels, ST7 only in rats and ST15 only in voles.
Most of ST1, ST3–ST5 and ST17 were reported from Asia. ST6, ST7 and ST13 were isolated from Asia, whereas ST15 was reported only in Europe. ST17 was the only one reported from Africa, ST4 and ST17 from North America and ST1–ST3 and ST8 from South America.
3.7. Pooled Prevalence of Blastocystis sp. in Rodents Based On Subgroups
Table 3 and Figures S1–S5 show the prevalence of Blastocystis sp. in rodents by subgroup.
TABLE 3.
Subgroup analysis of Blastocystis sp. in rodents based on publication year, continent, WHO region, country and sample size.
| Subgroup variable | Prevalence % (95% CI) | Heterogeneity (Q) | df (Q) | I 2 (%) | p value |
|---|---|---|---|---|---|
| Publication year | |||||
| 2013–2016 | 16.3 (10.6–24.3) | 8.5 | 7 | 17.4 | 0.05 |
| 2017–2020 | 20.6 (13.7–29.7) | 192.9 | 26 | 86.5 | 0.05 |
| 2021–2024 | 13.8 (11.1–19.9) | 541.6 | 42 | 92.2 | 0.05 |
| Continent | |||||
| Africa | 25 (3.4–76.2) | 0 | 0 | 0 | 0.05 |
| Asia | 12.9 (9.8–17) | 647.1 | 54 | 91.6 | 0.05 |
| Europe | 35.2 (21.3–52.1) | 37.7 | 14 | 62.9 | 0.05 |
| North America | 22.2 (8.7–46.1) | 10.1 | 3 | 70.3 | 0.05 |
| South America | 30.1 (7.6–69.1) | 9.1 | 2 | 77.9 | 0.05 |
| WHO region | |||||
| AMR | 25.6 (13–44) | 19.5 | 6 | 69.2 | 0.05 |
| EMR | 17.7 (9.1–31.5) | 77.5 | 9 | 88.4 | 0.05 |
| EUR | 35.2 (21.3–52.1) | 37.7 | 14 | 62.9 | 0.05 |
| SEAR | 20.6 (8.7–41.6) | 13.2 | 6 | 54.5 | 0.05 |
| WPR | 11.4 (8.1–15.7) | 551 | 38 | 93.1 | 0.05 |
| Country | |||||
| Belgium | 40 (10–80) | 0 | 0 | 0 | 0.05 |
| Brazil | 29.5 (2.4–87.9) | 9 | 1 | 88.9 | 0.05 |
| China | 11.1 (8.1–15) | 417 | 39 | 90.6 | 0.05 |
| Colombia | 30 (10–62.4) | 0 | 0 | 0 | 0.05 |
| France | 36 (15.3–63.7) | 3 | 4 | 0 | 0.05 |
| Indonesia | 13 (7.1–22.5) | 0 | 0 | 0 | 0.05 |
| Iran | 15.3 (6.4–32.3) | 48.7 | 5 | 89.7 | 0.05 |
| Japan | 44 (39.3–48.7) | 0 | 0 | 0 | 0.05 |
| Libya | 25 (3.4–76.2) | 0 | 0 | 0 | 0.05 |
| Mexico | 22.2 (8.7–46.1) | 10.1 | 3 | 70.3 | 0.05 |
| Poland | 7.1 (1–37) | 0 | 1 | 0 | 0.05 |
| Thailand | 23.7 (8.4–51.5) | 9.2 | 5 | 45.8 | 0.05 |
| Turkey | 61.1 (47.6–73.1) | 0 | 0 | 0 | 0.05 |
| The UAE | 50 (16.8–83.2) | 0 | 0 | 0 | 0.05 |
| The United Kingdom | 36.9 (13.2–69.2) | 21 | 5 | 76.2 | 0.05 |
| Sample size | |||||
| ≤100 | 19.6 (15–25.2) | 301.5 | 59 | 80.4 | 0.05 |
| >100 | 9.9 (6.1–15.7) | 426.9 | 17 | 96 | 0.05 |
3.8. Sensitivity Analysis
The sensitivity analysis indicated that excluding certain datasets on Blastocystis sp. in rodents did not significantly affect the overall frequency (Figure S6).
3.9. Publication Bias
The current systematic review and meta‐analysis revealed a notable publication bias (Egger's regression: intercept = −1.591, 95% lower limit = −2.7, 95% upper limit = −0.47, t value = 2.83, p = 0.005) (Figure 5).
FIGURE 5.
Publication bias in the present study.
4. Discussion
Systematic reviews and meta‐analyses have determined the global prevalence of Blastocystis sp. in various animals: cattle (Shams et al. 2021), sheep, goats (Shams, Asghari, et al. 2022), dogs, cats (Shams, Shamsi, et al. 2022) and pigs (Asghari, Sadrebazzaz, et al. 2021), as well as in specific human groups, including haemodialysis, cancer, HIV/AIDS and transplant recipients (Asghari, Sadeghipour, et al. 2021). This study revealed a global prevalence of Blastocystis sp. in rodent populations at 16% (95% CI: 12.6%–20.2%), higher than in dogs, cats and immunocompromised individuals, but lower than in cattle, sheep, goats and pigs. Global prevalence refers to the prevalence rate derived from available data, which indicates that differences across animal populations may be influenced by sample size, number of studies, diagnostic methods, animal types, housing and feeding conditions, and geographical location.
Voles and squirrels showed the highest Blastocystis sp. infection rates among rodents, whereas civets and porcupines had the lowest, despite variations in dataset numbers and sample sizes across species. This pattern suggests a potential ecological or behavioural influence on the prevalence of Blastocystis sp. across different rodent species. For instance, the dietary habits and habitat preferences of voles and squirrels may facilitate more frequent interactions with the pathogen, possibly through higher exposure to contaminated environments or food sources. In contrast, the lower infection rates in civets and porcupines could indicate either a natural resistance to the pathogen or different ecological niches that limit exposure. Furthermore, it is essential to consider the role of host genetics and immune response, which may vary significantly among species. Genetic factors could contribute to varying susceptibilities, influencing how different rodent populations respond to environmental pathogens like Blastocystis sp. In addition, the variations in dataset sizes and methodologies used in sampling could introduce biases that affect the accuracy of infection rate assessments. Future studies should aim for standardized sampling techniques across various species to obtain a more comprehensive understanding of the dynamics of Blastocystis sp. infections in wildlife.
High genetic diversity in the genus Blastocystis sp., as indicated by the small subunit of the ribosomal RNA gene (SSU rRNA), has resulted in its classification into various STs (Stensvold, Alfellani, and Clark 2012). So far, around 44 STs of Blastocystis sp. have been identified, with 16 being zoonotic (ST1‐ST10, ST12, ST14, ST16, ST23, ST35 and ST41) and capable of transmission between humans and animals (Liu et al. 2024; Santin et al. 2024). Of note, the genetic diversity of Blastocystis sp. extends beyond these 44 STs, and forthcoming studies are expected to uncover additional animal and zoonotic STs. The current findings indicate that among the 12 STs (ST1–ST8, ST10, ST13, ST15, ST17) isolated from rodents, 9 STs (ST1–ST8 and ST10) possess zoonotic properties, highlighting the crucial role of these animals in transmitting Blastocystis sp. zoonotic infections to vulnerable human populations and vice versa. Of note, to unequivocally demonstrate the zoonotic transmission of Blastocystis sp. between humans and animals, two conditions must be met: Both must coexist in the same spatiotemporal context, and they must possess the same species and genotype. Transmission of Blastocystis sp. infection from wild rodents outside human habitats can be relatively low. In contrast, commensal rodents near human dwellings can transmit various microorganisms, including Blastocystis sp., to humans and pets, potentially leading to mild to severe health complications (Himsworth et al. 2013; Dahmana et al. 2020; Islam et al. 2021).
The rodent‐specific ST (ST4) was the most common globally among rodents, followed by ST5, ST1, ST3, ST2, ST13, ST17, ST6, ST7, ST8, ST10 and ST15. Several of these STs (ST1–ST8 and ST10) have zoonotic potential, having been isolated from humans and other animals as well. This underscores the need to monitor these STs in both wildlife and domestic populations, as their presence in various hosts can reveal insights into their evolutionary dynamics and potential public health impacts. The country‐based distribution of Blastocystis sp. STs in rodents showed that the highest sample numbers came from China, Japan, Iran, the United Kingdom and Mexico, respectively. China and the United Kingdom displayed the most ST diversity, with 10 (ST1–ST7, ST10, ST13, ST17) and 7 (ST1–ST5, ST10, ST15) distinct STs, respectively. Notably, ST6, ST7 and ST13 were exclusive to China, whereas ST15 was found only in the United Kingdom. The distribution patterns of Blastocystis sp. STs across various regions suggest that ecological and environmental factors significantly influence these communities. The exclusive presence of ST6, ST7 and ST13 in China, along with ST15 in the United Kingdom, raises important questions about the evolutionary pathways and host interactions of Blastocystis sp. in different rodent species. Ongoing research into the genetic characteristics and environmental links of these STs is vital for understanding their epidemiology and potential zoonotic transmission risks. Analysing these biogeographical patterns underscores the value of localized studies in elucidating the ecological relationships between Blastocystis sp. and their rodent hosts.
Species‐based analysis revealed that most rodent samples came from rats, squirrels, mice, coypus, civets, porcupines and voles. Squirrels, rats, mice and voles exhibited the highest ST diversity of Blastocystis sp., with 8 (ST1‐ST6, ST13, ST17), 7 (ST1‐ST5, ST7, ST17), 5 (ST1, ST3–ST5, ST10) and 5 (ST1, ST4, ST5, ST10, ST15) distinct STs, respectively. Notably, ST6 and ST13 were found only in squirrels, ST7 exclusively in rats and ST15 solely in voles. The analysis indicated a significant variation in the prevalence of the distinct STs among the different rodent species, suggesting potential host‐specificity. For instance, although both squirrels and rats exhibited a rich diversity of STs, the presence of STs such as ST6 and ST13 in squirrels might indicate a particular ecological niche or dietary preference that supports these STs of Blastocystis sp. Conversely, the exclusive occurrence of ST7 in rats could suggest a specialized adaptation of this ST to the physiological or environmental conditions unique to the rat habitats. On the other hand, contamination of rodents with human and animal STs in various environments can lead to ST diversity among rodent species. Thus, isolating specific STs from a particular rodent species does not necessarily indicate that subtype's exclusivity to that rodent. However, further investigations into the geographical distribution of these rodent species may shed light on the dynamics of Blastocystis sp. transmission. Understanding the interactions between rodent hosts and their associated environmental factors could reveal critical insights into the epidemiology of Blastocystis sp.
Most Blastocystis sp. STs in rodents were reported in Asia, with ST6, ST7 and ST13 isolated exclusively from there. ST15 was found only in Europe, ST17 was unique to Africa, and both ST4 and ST17 were reported in North America, whereas ST1–ST3 and ST8 were from South America. The distribution of Blastocystis sp. STs highlights the intricate interplay between host species and environmental factors. In addition to the geographic isolation of specific STs, studies indicate that the prevalence of certain STs may be influenced by rodent population densities and local ecological conditions. Moreover, the genetic diversity observed within these STs offers insights into their evolutionary pathways and adaptation mechanisms. Overall, the limited studies and narrow geographical focus hinder a thorough investigation of Blastocystis sp. STs in specific regions and rodent species, a discussion that will improve as research in this area advances.
The sensitivity analysis showed that there was no outlier data among the 34 studies/78 datasets entered, and no statistically significant change was reported in the prevalence of Blastocystis sp. in rodents by removing individual datasets. The subgroup analysis revealed no direct association between publication year and the prevalence of Blastocystis sp. in rodents, with the highest prevalence recorded at 20.6% (95% CI: 13.7%–29.7%) between 2017 and 2020. Rodents in Europe and the EUR WHO region exhibited a higher prevalence of Blastocystis sp. infection, based on 14 analysed datasets. Among the countries studied, Turkey (61.1%; 95% CI: 47.6%–73.1%), the UAE (50%; 95% CI: 16.8%–83.2%), Japan (44%; 95% CI: 39.3%–48.7%) and Belgium (40%; 95% CI: 10%–80%) showed the highest infection rates compared to the other 11 evaluated countries. A global study found a direct link between larger sample sizes and reduced prevalence of Blastocystis sp. in rodents, suggesting that epidemiological studies need sufficient sample sizes to accurately reflect disease or infection prevalence. Overall, due to challenges in identifying wild rodents, mixing of nearby rodent groups and solitary animals, the interpretation of sample numbers and Blastocystis sp. prevalence in rodents may involve various errors.
Of note, it is important to emphasize the importance of cats and dogs as key intermediate hosts in the transmission of parasitic infections, such as Blastocystis sp., between rodents and humans. These animals serve as significant vectors in the zoonotic transmission of various pathogens, acting as reservoirs that facilitate the lifecycle of parasites. Their interactions with both wild and domestic rodent populations create a dynamic ecological relationship that heightens the risk of infection in humans. As these pets come into contact with contaminated environments, such as parks, yards, or homes where rodents may reside, they inadvertently carry and spread infectious agents like Blastocystis sp. (Morelli et al. 2021; Macpherson et al. 2022). Moreover, new pets like ferrets, weasels and polecats consume small mammals such as rabbits, mice, rats and other rodents, serving as reservoirs for parasitic infections like Blastocystis sp., which facilitate the human infections and lifecycle of parasites. The environmental contamination from their faeces can spread pathogens, creating a cycle that may inadvertently infect humans (Powers 2009; Vinke and Schoemaker 2012). Therefore, pet owners must adhere to strict hygiene practices, including regular cage cleaning and proper waste disposal.
To prevent the transmission of parasitic infections such as Blastocystis sp. from rodents to humans and domestic animals, the following measures can be taken: (1) Utilize integrated pest management (IPM) strategies to reduce rodent populations through traps and environmental management to eliminate food and shelter sources. (2) Maintenance of cleanliness in and around homes, farms and food storage areas to deter rodent infestations by properly disposing of garbage and securely storing food. (3) Encouraging regular handwashing, especially after handling animals, cleaning up rodent droppings, or working in areas where rodents may be present. (4) Educating communities about the risks of rodent‐borne parasites and the importance of control measures. (5) Monitoring rodent populations and potential parasitic infections within local wildlife and domestic animals to quickly identify and respond to outbreaks. (6) Ensuring regular veterinary check‐ups for pets and livestock to detect and treat any parasitic infections early. (7) Environmental modification to reduce rodent access to buildings by sealing entry points and removing debris or clutter (Thompson, Kutz, and Smith 2009; Esch and Petersen 2013; Mackenstedt, Jenkins, and Romig 2015; Mustapha et al. 2019). Implementing these measures can significantly reduce the risk of parasite transmission from rodents to humans and domestic animals.
The current study found significant publication bias among the included studies, likely due to factors such as lack of studies in various geographical areas, the existence of a large number of studies on certain species of rodents and so forth (Kicinski 2013). This study, like many reviews, has limitations, primarily due to analyses based on single studies or datasets and limited geographical diversity. Therefore, the present results should be interpreted with care and caution.
5. Conclusion
This systematic review and meta‐analysis revealed a global Blastocystis sp. infection rate of 16% in rodent populations, underscoring the influence of ecological and behavioural factors, particularly among voles and squirrels, on pathogen exposure. However, the number of included studies and examined samples of different species in this interpretation should not be ignored. The identification of 12 STs, 9 of which have zoonotic potential, highlights rodents as significant reservoirs for zoonotic transmission, especially in urban settings. The study calls attention to the geographical diversity of these STs, particularly in China and the United Kingdom, emphasizing the role of local conditions in Blastocystis sp. epidemiology. Moreover, the need for standardized research methods is critical due to identified publication bias, which hampers accurate prevalence estimates. Ongoing research should expand geographic focus and explore rodent‐environment interactions to clarify transmission pathways. Overall, our findings stress the necessity of monitoring Blastocystis sp. in wildlife and domestic populations, alongside effective public health measures to mitigate zoonotic risks and protect vulnerable human communities.
Author Contributions
Planned and designed the study: Ali Asghari and Amir Farzam. Involved in the methodology: Ali Asghari, Amin Karampour, Seyedeh‐Sara Nazem‐Sadati and Parisa Sadat‐Madani. Conducted the statistical analysis: Ali Asghari. Wrote the manuscript and revised it: Ali Asghari and Amir Farzam. All authors have read and approved the final manuscript.
Conflicts of Interest
The authors declare no conflicts of interest.
Supporting information
Figure S1
Figure S2
Figure S3
Figure S4
Figure S5
Figure S6
Figure S7
Acknowledgements
The current study was financed by the Vice‐Chancellor for Research of Qazvin University of Medical Sciences, Qazvin, Iran. Hereby, we express our gratitude and appreciation for the comprehensive support of this centre.
Funding: The current study was financed by the Vice‐Chancellor for Research of Qazvin University of Medical Sciences, Qazvin, Iran.
Data Availability Statement
The datasets used and/or analysed during the current study are available in the online version.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Figure S1
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Data Availability Statement
The datasets used and/or analysed during the current study are available in the online version.