Buffalopox is an emerging and re-emerging zoonotic viral infection. The authors investigated an extensive zoonotic outbreak of buffalopox involving many human cases. High morbidity and significant productivity losses were recorded among domestic buffalo in Kolhapur (Maharashtra), India, between February and March 2009. The outbreak involved a total of 4000 buffalo from 21 villages in which over 10 000 buffalo were herded. The outbreak also involved 125 humans who were mostly animal handlers and milkers of all age groups. The disease inflicted a loss of approximately 40% in terms of reduced milk production and a decline in animal trade. Although pox lesions were observed on all parts of the body, the most severe were found on the inner ear. This led to otitis and pyrexia in most of the affected animals. Milkers developed pox-like lesions on the skin of their fingers, hands, forearms, forehead, ears and face, along with pyrexia, malaise and axillary lymphadenitis and lymphadenopathy. The causal agent, buffalopox virus, was confirmed using counter-immuno-electrophoresis, the serum neutralisation test, virus isolation and buffalopox virus-specific ankyrin repeat protein (C18L) gene-based polymerase chain reaction. Considering the emergence and re-emergence of buffalopox virus in buffalo, cows and humans, not only in India but also in other buffalo rearing countries, regular monitoring of outbreaks and control measures are necessary to curb economic losses and also to reduce the public health impact of the disease.