Rotavirus group C spreads across Brazil's pig farms, raising mortality and costs

Recent laboratory data from Brazil show a sharp rise in group C rotavirus (RVC) detections in neonatal piglets. In a three‑year Inata study, 35.2% of diarrheic piglet samples tested positive for any rotavirus, with 17.7% specifically positive for RVC. A 2025 Canadian case‑control study of 19 Brazilian farrowing units found RVC in 100% of farms during diarrhea outbreaks and linked its presence to a 7.1‑fold increase in the odds of neonatal diarrhea (p = 0.02), while group A rotavirus showed no significant association.

RVC infection damages intestinal microvilli, causing watery, yellow‑ish diarrhea, rapid dehydration, and secondary bacterial or parasitic infections. The virus is also frequently detected in the farrowing environment—bays, doors, ventilators, and mobile panels—indicating environmental persistence and inadequate sanitation practices. Because commercial vaccines target only group A, passive immunity from sows does not protect against RVC, leading to higher morbidity, reduced weight gain, and increased feed and medication costs for growers.

The spread of RVC has been reported across virtually all major pork‑producing regions in Brazil, affecting both high‑technology and isolated farms. Producers face uneven growth rates, higher mortality, and longer times to market weight, translating into significant financial losses for the sector in 2026.