A meticulous systematic review has cast new light on the battle against Equine Herpes Virus type 1 (EHV-1), a formidable adversary responsible for upper respiratory disease, neurological disorders, abortions, and neonatal fatalities in horses. The critical question at the heart of this research: Can pharmacological therapy effectively reduce the incidence or severity of EHV-1 in domesticated horses?

To find answers, researchers embarked on an extensive search across several databases, including AGRICOLA, CAB Abstracts, Cochrane, PubMed, Web of Science, and WHO Global Health Index Medicus Regional Databases, collating articles published before February 15, 2021. The criteria for selection were strict, focusing solely on original research reports in peer-reviewed journals that delved into the in vivo use of therapeutic agents against EHV-1 in horses, looking closely at clinical outcomes and infection rates.

Out of an initial pool of 7009 studies, only 9 made the cut, covering a range of interventions from valacyclovir and small interfering RNAs to more unconventional treatments like a Parapoxvirus ovis-based immunomodulator, human alpha interferon, herbal supplements, a cytosine analog, and heparin. The research varied in its methodology, including both randomized controlled studies and observational trials, though it was hampered by moderate to high risk of bias and generally small sample sizes.

he level of evidence ranged between randomized controlled studies and observational trials. The risk of bias was moderate to high and sample sizes were small. Most studies reported either no benefit or minimal efficacy of the intervention tested.

READ the full study here: https://onlinelibrary.wiley.com/doi/10.1111/jvim.17016