Rotavirus infection is the leading cause of diarrhea in foals, resulting in severe dehydration and electrolyte imbalances that can quickly become fatal if untreated. Until 2021, equine rotavirus group A (ERVA) was thought to be the sole rotavirus affecting horses; however, recent findings have identified equine rotavirus group B (ERVB) as a contributor to outbreaks of diarrhea in neonatal foals. ERVA has been detected globally in numerous countries with significant equine populations. Equine rotaviruses (ERVs) are highly contagious, and foals as young as 12 hours of age can exhibit clinical symptoms. These symptoms include loss of appetite, lethargy, colic, and distinctive watery diarrhea that may appear orange-yellow to reddish-brown. Currently, diagnosis relies primarily on quantitative PCR (qPCR), which has limitations since it requires prior knowledge of the pathogen’s genome. Supportive care is the cornerstone of treatment for rotaviral diarrhea, as there are no specific antiviral therapies available. Prevention strategies focus on implementing effective biosecurity measures and, in the case of ERVA, vaccinating mares.