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Veterinary world2025; 18(6); 1440-1451; doi: 10.14202/vetworld.2025.1440-1451

Global prevalence and risk factors of equine infectious anemia: A systematic review and meta-analysis.

Abstract: Equine infectious anemia (EIA) is a lentiviral disease affecting members of the Equidae family, with global distribution and significant implications for animal health and biosecurity. Despite numerous individual reports, a comprehensive synthesis of its global prevalence and risk factors remains lacking. This study aimed to conduct a systematic review and meta-analysis to estimate the global prevalence of EIA, identify diagnostic trends, and evaluate factors associated with heterogeneity across studies. Unassigned: A systematic search was conducted in six major databases (PubMed, Scopus, Web of Science, ScienceDirect, Cochrane Library, and ProQuest), yielding 312 records. After Preferred Reporting Items for Systematic Reviews and Meta-Analyses-guided screening, 29 eligible studies published between 1975 and 2024 were included in the study. Meta-analysis was performed using R Studio (version 4.4.2) employing a random-effects model. Subgroup analyses and meta-regression were conducted to explore heterogeneity across host species, continent, diagnostic method, and study period. Publication bias was assessed through funnel plots and Egger's test. Unassigned: The global pooled prevalence of EIA was estimated at 20.97% (95% confidence interval [CI]: 11.08-30.85), with substantial heterogeneity (I = 99.3%). South America reported the highest regional prevalence (27.21%), while horses showed the greatest susceptibility among Equidae (25.40%). Diagnostic methods varied, with agar gel immunodiffusion being the most commonly used (18.62% prevalence detection). A declining trend in prevalence (2.19%-28.70%) was noted from 2015 to 2022. No significant publication bias was detected. Meta-regression revealed that climate and study period partially explained the heterogeneity. Unassigned: This study highlights the substantial global burden and diagnostic variability of EIA, emphasizing the need for enhanced surveillance in endemic areas, standardized diagnostic protocols, and strengthened quarantine practices. Expanding serological monitoring in underrepresented regions and integrating climatic and ecological data into control strategies are vital for mitigating EIA transmission risks.
Publication Date: 2025-06-06 PubMed ID: 40689174PubMed Central: PMC12269943DOI: 10.14202/vetworld.2025.1440-1451Google Scholar: Lookup
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Summary

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This research is a systematic review and meta-analysis on the global prevalence and risk factors of Equine Infectious Anemia (EIA), a viral disease impacting the Equidae family of animals, such as horses. The study reveals a significant worldwide presence of EIA and underscores the need for better surveillance, standardized diagnostic procedures, and robust quarantine protocols to manage it.

Study Methodology

  • The research team carried out a systematic search in six significant databases: PubMed, Scopus, Web of Science, ScienceDirect, Cochrane Library, and ProQuest. They selected 29 studies that met their criteria out of 312 records found.
  • These studies were conducted between 1975 and 2024 and were included for data harvesting and analysis.
  • A meta-analysis was performed using the R Studio software, specifically the ‘random-effects model’ to handle the diversity in study characteristics.
  • They employed subgroup analyses and meta-regression techniques to investigate the variability across different factors such as host species, geographic region, diagnostic methods, and time period of the study.
  • Publication bias, which refers to the tendency of researchers to publish only positive or significant results, was also assessed.

Study Findings

  • The researchers estimated that the global prevalence of EIA is about 20.97%, though this estimate varied greatly across different regions, species, and diagnostic methods (known as ‘heterogeneity’).
  • They found that the highest regional prevalence was in South America (27.21%), and among the Equidae family, horses were the most susceptible (25.40%).
  • The most commonly used diagnostic method was agar gel immunodiffusion, which detected a prevalence of 18.62%.
  • The researchers observed a downward trend in prevalence from 2015 to 2022 (from 28.70% down to 2.19%).
  • No significant publication bias was detected in the studies they analyzed. The meta-regression analysis suggested that climate and the time period of study were factors in the observed heterogeneity.

Implications and Recommendations

  • This study underlines the substantial global burden of EIA and the variability in its diagnosis, emphasizing the need for improved disease surveillance in areas where EIA is common (endemic areas).
  • Implementing standardized diagnostic protocols and enforcing stricter quarantine practices could help manage the risk of EIA spread.
  • It recommends extending serological monitoring (blood tests that detect antibodies against the virus) to regions that are currently underrepresented in the research.
  • The inclusion of climate and ecological data in EIA control strategies could help in handling the disease more effectively.

Cite This Article

APA
Firdausy LW, Fikri F, Wicaksono AP, Çalışkan H, Purnama MTE. (2025). Global prevalence and risk factors of equine infectious anemia: A systematic review and meta-analysis. Vet World, 18(6), 1440-1451. https://doi.org/10.14202/vetworld.2025.1440-1451

Publication

ISSN: 0972-8988
NlmUniqueID: 101504872
Country: India
Language: English
Volume: 18
Issue: 6
Pages: 1440-1451

Researcher Affiliations

Firdausy, Lintang Winantya
  • Division of Veterinary Medicine, Department of Health and Life Sciences, Faculty of Health, Medicine, and Life Sciences, Universitas Airlangga, Banyuwangi, East Java, 68425, Indonesia.
  • Research Group of Animal Biomedical and Conservation, Faculty of Health, Medicine, and Life Sciences, Universitas Airlangga, Banyuwangi, East Java, 68425, Indonesia.
Fikri, Faisal
  • Division of Veterinary Medicine, Department of Health and Life Sciences, Faculty of Health, Medicine, and Life Sciences, Universitas Airlangga, Banyuwangi, East Java, 68425, Indonesia.
  • Research Group of Animal Biomedical and Conservation, Faculty of Health, Medicine, and Life Sciences, Universitas Airlangga, Banyuwangi, East Java, 68425, Indonesia.
Wicaksono, Arya Pradana
  • Animal Health Division, Indonesian Horse Veterinarian Association, Surabaya, East Java, 60115, Indonesia.
Çalışkan, Hakan
  • Department of Biology, Faculty of Science, Eskisehir Osmangazi University, Eskisehir, 26040, Turkey.
Purnama, Muhammad Thohawi Elziyad
  • Division of Veterinary Medicine, Department of Health and Life Sciences, Faculty of Health, Medicine, and Life Sciences, Universitas Airlangga, Banyuwangi, East Java, 68425, Indonesia.
  • Research Group of Animal Biomedical and Conservation, Faculty of Health, Medicine, and Life Sciences, Universitas Airlangga, Banyuwangi, East Java, 68425, Indonesia.
  • Department of Biology, Graduate School of Natural and Applied Sciences, Eskisehir Osmangazi University, Eskisehir, 26040, Turkey.

Conflict of Interest Statement

The authors declare that they have no competing interests.

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