First serological evidence of equine coronavirus and severe acute respiratory syndrome coronavirus 2 in horses in North Africa.
Abstract: Viral diseases cause significant economic losses within the equine population. Horses are susceptible to equine coronavirus (ECoV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), although only ECoV has been associated to clinical disease. The aim of this study was to investigate, for the first time in Algeria, the seroprevalence of ECoV and SARS-CoV-2 antibodies and the prevalence of ECoV infection in horses. In 2022, a total of 299 serum samples was collected from horses aged 1 to 27 years. Serological analysis for the presence of ECoV and SARS-CoV-2 was performed using a validated in-house and a commercially available ELISA, respectively. In addition, fecal samples of these animals were tested for the presence of ECoV RNA by RT-qPCR. SARS-CoV-2-ELISA positive sera with high S/P ratios and negative samples close to the doubtful threshold were retested using a virus neutralization test (VNT). The seroprevalence of ECoV and SARS-CoV-2 in the tested horses was 63.5% (190/299) and 4.3% (13/299), respectively. Among CoVs-seropositive horses, six were seropositive for both ECoV and SARS-CoV-2, thus 6/10 sera were VNT positive, including two ELISA-negative samples for SARS-CoV-2. ECoV seroprevalence varied according to age, breed and sex. None of the fecal samples tested positive for ECoV. Antibodies against SARS-CoV-2 were confirmed by VNT in six samples (2%). One SARS-CoV-2-positive serum tested by ELISA and confirmed through VNT was cytotoxic for VERO cells. This study is the first to report the circulation of ECoV and SARS-CoV-2 in the Algerian horse population. Further studies are necessary to isolate and obtain molecular characterisation of ECoV and SARS-CoV-2 from horses in Algeria.
© 2025. The Author(s), under exclusive licence to Springer Nature B.V.
Publication Date: 2025-10-04 PubMed ID: 41045398PubMed Central: 10122986DOI: 10.1007/s11259-025-10928-0Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
Overview
- This study provides the first evidence of the presence of antibodies to equine coronavirus (ECoV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in horses in North Africa, specifically Algeria.
- It assesses the prevalence of these viruses in horses and investigates factors linked to exposure, offering insight into potential health risks for the equine population.
Background and Purpose
- Equine coronavirus (ECoV) and SARS-CoV-2 are viruses that can infect horses, with ECoV known to be associated with clinical disease while the impact of SARS-CoV-2 on horses remains unclear.
- Viral diseases in horses cause significant economic losses, making surveillance important for animal health and agriculture.
- This research aimed to determine the presence of antibodies against ECoV and SARS-CoV-2 in horses in Algeria, thus indicating past exposure or infection.
- It also sought to detect active ECoV infections through RNA presence in fecal samples.
Methods
- A total of 299 horses, aged 1 to 27 years, were sampled in 2022.
- Blood serum samples were collected for serological testing of antibodies against ECoV and SARS-CoV-2.
- ECoV antibodies were tested using an in-house validated ELISA (enzyme-linked immunosorbent assay).
- SARS-CoV-2 antibodies were tested using a commercially available ELISA.
- Fecal samples were tested for ECoV RNA using RT-qPCR to detect active viral infection.
- Samples with high or borderline SARS-CoV-2 antibody levels were retested using a virus neutralization test (VNT) to confirm the presence of neutralizing antibodies, which are indicative of true viral exposure.
Key Findings
- Equine coronavirus antibody seroprevalence was 63.5% (190 out of 299 horses), indicating that a majority of tested horses had been exposed to ECoV.
- SARS-CoV-2 antibody seroprevalence was 4.3% (13 out of 299 horses), demonstrating evidence of SARS-CoV-2 infection or exposure in the horse population for the first time in Algeria.
- Six horses were seropositive for both ECoV and SARS-CoV-2, suggesting some overlap in exposure.
- Among these, 6 out of 10 sera samples were VNT positive, indicating confirmed neutralizing antibodies, including two samples that were ELISA-negative but VNT-positive, showing that VNT can capture cases missed by ELISA.
- ECoV seroprevalence varied based on age, breed, and sex of the horses, suggesting these factors influence exposure risk or immune response.
- No fecal samples tested positive for ECoV RNA, so no active ECoV infection was detected at the time of sampling.
- Six serum samples (2%) were confirmed positive for SARS-CoV-2 antibodies via virus neutralization test.
- One SARS-CoV-2 positive serum sample was cytotoxic to VERO cells during testing, indicating potential challenges in laboratory handling or unusual sample characteristics.
Implications and Future Directions
- This research is pioneering in documenting the circulation of both ECoV and SARS-CoV-2 in horses in Algeria and more broadly North Africa.
- The high seroprevalence of ECoV indicates widespread exposure, which may have clinical and economic implications for the local equine industry.
- The presence of SARS-CoV-2 antibodies in horses suggests that these animals can be exposed to the virus responsible for COVID-19 in humans, raising questions about potential cross-species transmission and the role of horses in the epidemiology of SARS-CoV-2.
- The absence of active ECoV infections (negative fecal samples) could mean either low viral shedding at sampling or transient viral infection phases.
- Further studies are needed to isolate these viruses directly from horses to characterize viral strains and better understand the disease dynamics.
- More molecular research will be necessary to study the genetics of the circulating viruses and confirm if strains found in horses share similarities with those infecting humans or other species.
- Results highlight the importance of ongoing surveillance in animal populations for emerging viral pathogens that could impact animal and human health.
Cite This Article
APA
Kouadria W, Poder SL, van Maanen K, Seuberlich T, Dawson KLD, Zientara S, Laabassi F.
(2025).
First serological evidence of equine coronavirus and severe acute respiratory syndrome coronavirus 2 in horses in North Africa.
Vet Res Commun, 49(6), 347.
https://doi.org/10.1007/s11259-025-10928-0 Publication
Researcher Affiliations
- PIAD Research Team, ESPA Laboratory, Department of Veterinary, Institute of Veterinary Sciences and Agronomic Sciences, University of Batna-1, Batna, 05000, Algeria.
- bUMR Virologie, Ecole nationale vétérinaire d'Alfort, Anses, INRAE, Laboratoire de Santé Animale, Maisons-Alfort, Anses, F-94700, France.
- Royal GD, Arnsbergstraat 7, 7418 EZ Deventer, The Netherlands.
- Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
- Division of Neurological Sciences, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
- bUMR Virologie, Ecole nationale vétérinaire d'Alfort, Anses, INRAE, Laboratoire de Santé Animale, Maisons-Alfort, Anses, F-94700, France.
- PIAD Research Team, ESPA Laboratory, Department of Veterinary, Institute of Veterinary Sciences and Agronomic Sciences, University of Batna-1, Batna, 05000, Algeria. farouk.laabassi@univ-batna.dz.
MeSH Terms
- Animals
- Horses
- Horse Diseases / epidemiology
- Horse Diseases / virology
- Seroepidemiologic Studies
- Female
- Algeria / epidemiology
- COVID-19 / veterinary
- COVID-19 / epidemiology
- COVID-19 / virology
- Male
- SARS-CoV-2 / isolation & purification
- SARS-CoV-2 / immunology
- Antibodies, Viral / blood
- Enzyme-Linked Immunosorbent Assay / veterinary
- Feces / virology
- Coronavirus / isolation & purification
Conflict of Interest Statement
Declarations. Ethics approval: The authors confirm that ethical review is not required from this work in their region. Blood samples were collected by the researchers (veterinarians) after getting informed consent from the owners of the horses. All efforts were made to minimize animal suffering during sample collection. Oral and written informed consent was obtained from all people who participated in the study. Competing interests: The authors declare no competing interests.
References
This article includes 31 references
- Bannai H, Kambayashi Y, Ohta M, Nemoto M, Tsujimura K. Prevalence of serum and salivary virus-neutralizing antibodies against equine coronavirus in four riding stables in Japan. J Equine Sci 34(1):13–18.
- Berryhill EH, Magdesian KG, Aleman M, Pusterla N. Clinical presentation, diagnostic findings, and outcome of adult horses with equine coronavirus infection at a veterinary teaching hospital: 33 cases (2012–2018). Vet J 248:95–100.
- Bosco-Lauth AM, Walker A, Guilbert L, Porter S, Hartwig A, McVicker E, Bielefeldt-Ohmann H, Bowen RA. Susceptibility of livestock to SARS-CoV-2 infection. Emerg Microbes Infect 10(1):2199–2201.
- Bryan J, Marr CM, MacKenzie CJ, Mair TS, Fletcher A, Cash R, Phillips M, Pusterla N, Mapes S, Foote AK. Detection of equine coronavirus in horses in the United Kingdom. Vet Rec 184(4):123.
- Fielding CL, Higgins JK, Higgins JC, Mcintosh S, Scott E, Giannitti F, Mete A, Pusterla N. Disease associated with equine coronavirus infection and high case fatality rate. J Vet Intern Med 29(1):307–310.
- Goodrich EL, Mittel LD, Glaser A, Ness SL, Radcliffe RM, Divers TJ. Novel findings from a beta coronavirus outbreak on an American miniature horse breeding farm in upstate New York. Equine Vet Educ 32(3):150–154.
- Guy JS, Breslin JJ, Breuhaus B, Vivrette S, Smith LG. Characterization of a coronavirus isolated from a diarrheic foal. J Clin Microbiol 38(12):4523–4526.
- Hemida MG, Chu DKW, Perera RAPM, Ko RLW, So RTY, Ng BCY, Chan SMS, Chu S, Alnaeem AA, Alhammadi MA, Webby RJ, Poon LLM, Balasuriya UBR, Peiris M. Coronavirus infections in horses in Saudi Arabia and Oman. Transbound Emerg Dis 64(6):2093–2103.
- Hierweger MM, Remy-Wohlfender F, Franzen J, Koch MC, Blau D, Schoster A, Nicholson P, Gerber V, Gurtner C, Fouché N, Unger L, Seuberlich T. Outbreak of equine coronavirus disease in adult horses, Switzerland 2021. Transbound Emerg Dis 69(4):1691–1694.
- Horner S, Agne GF, Byrne DP, Bain ME, Lynch BM, Gow WR, Verdegaal E-LJMM. Case series report: equine coronavirus in Australia. AVJ 103(1–2):56–62.
- Hüttl J, Reitt K, Meli ML, Meili T, Bönzli E, Pineroli B, Ginders J, Schoster A, Jones S, Tyson GB, Hosie MJ, Pusterla N, Wernike K, Hofmann-Lehmann R. Serological and molecular investigation of SARS-CoV-2 in horses and cattle in Switzerland from 2020 to 2022. Viruses 16(2):224.
- Kambayashi Y, Bannai H, Tsujimura K, Hirama A, Ohta M, Nemoto M. Outbreak of equine coronavirus infection among riding horses in Tokyo. Japan Comp Immunol Microbiol Infect Dis 77:101668.
- Kambayashi Y, Nemoto M, Tsujimura K, Ohta M, Bannai H. Serosurveillance of equine coronavirus infection among thoroughbreds in Japan. Equine Vet J 55(3):481–486.
- Kooijman LJ, James K, Mapes SM, Theelen MJP, Pusterla N. Seroprevalence and risk factors for infection with equine coronavirus in healthy horses in the USA. Vet J 220:91–94.
- Laabassi F, Amelot G, Laugier C, Zientara S, Nasri AM, Hans A. Prevalence of equine viral arteritis in Algeria. Rev Sci Tech 33:967–974.
- Laabassi F, Beck C, Gaudaire D, Lecollinet S, Zientara S, Hans A. Seroprevalence of equine infectious anaemia virus (EIAV), equine arteritis virus (EAV) and West nile virus (WNV) in donkeys in Eastern Algeria in 2015. Equine Vet J 53(S56):37.
- Lawton K, Keller SM, Barnum S, Arredondo-Lopez C, Spann K, Pusterla N. Seroprevalence of SARS-CoV-2 in 1186 equids presented to a veterinary medical teaching hospital in California from 2020 to 2022. Viruses 14(11):2497.
- Lawton KOY, Arthur RM, Moeller BC, Barnum S, Pusterla N. Investigation of the role of healthy and sick equids in the COVID-19 pandemic through serological and molecular testing. Animals 12(5):614.
- Miszczak F, Tesson V, Kin N, Dina J, Balasuriya UBR, Pronost S, Vabret A. First detection of equine coronavirus (ECoV) in Europe. Vet Microbiol 171(1–2):206–209.
- Nemoto M, Oue Y, Morita Y, Kanno T, Kinoshita Y, Niwa H, Ueno T, Katayama Y, Bannai H, Tsujimura K, Yamanaka T, Kondo T. Experimental inoculation of equine coronavirus into Japanese draft horses. Arch Virol 159(12):3329–3334.
- Nemoto M, Oue Y, Higuchi T, Kinoshita Y, Bannai H, Tsujimura K, Yamanaka T, Kondo T. Complete genome analysis of equine coronavirus isolated in Japan. Arch Virol 160(11):2903–2906.
- Nemoto M, Schofield W, Cullinane A. The first detection of equine coronavirus in adult horses and foals in Ireland. Viruses 11(10):946.
- Oue Y, Ishihara R, Edamatsu H, Morita Y, Yoshida M, Yoshima M, Hatama S, Murakami K, Kanno T. Isolation of an equine coronavirus from adult horses with pyrogenic and enteric disease and its antigenic and genomic characterization in comparison with the NC99 strain. Vet Microbiol 150(1–2):41–48.
- Oue Y, Morita Y, Kondo T, Nemoto M. Epidemic of equine coronavirus at Obihiro racecourse, Hokkaido, Japan in 2012. J Vet Med Sci 75(9):1261–1265.
- Pusterla N, Mapes S, Wademan C, White A, Ball R, Sapp K, Burns P, Ormond C, Butterworth K, Bartol J, Magdesian KG. Emerging outbreaks associated with equine coronavirus in adult horses. Vet Microbiol 162:228–231.
- Pusterla N, Holzenkaempfer N, Mapes S, Kass P. Prevalence of equine coronavirus in nasal secretions from horses with fever and upper respiratory tract infection. Vet Rec 177(11):289.
- Pusterla N, Vin R, Leutenegger CM, Mittel LD, Divers TJ. Divers, enteric coronavirus infection in adult horses. Vet J 231:13–18.
- Pusterla N, Chaillon A, Ignacio C, Smith DM, Barnum S, Lawton KOY, Smith G, Pickering B. SARS-CoV-2 seroconversion in an adult horse with direct contact to a COVID-19 individual. Viruses 14(5):1–5.
- Pusterla N, Lawton K, Barnum S. Investigation of the seroprevalence to equine coronavirus and SARS-CoV-2 in healthy adult horses recently imported to the United States. Vet Q 44(1):1–6.
- Zhao S, Smits C, Schuurman N, Barnum S, Pusterla N, Van Kuppeveld F, Bosch BJ, Van Maanen K, Egberink H. Development and validation of a S1 protein-based ELISA for the specific detection of antibodies against equine coronavirus. Viruses 11(12):1109.
- Zhou Z, Qiu Y, Ge X. The taxonomy, host range and pathogenicity of coronaviruses and other viruses in the nidovirales order. Anim Dis 2021 1(1):1–28.
Citations
This article has been cited 0 times.Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists