We found cutaneous lesions on the unfeathered parts of the body in several house sparrows surveys carried out in Spain. Lesions were wart-like growths (0.5–6 mm in diameter) which can range in colour from yellow or white in the early stages to brown or black when the formation of crusty scabs become. Smaller lesions can be quite cryptic. Frequently these regions are bordered by erythema. The lesions were seen more frequently in lower legs and feet (S1 Fig). The mean prevalence of pox-like lesions in a survey of 2,341 house sparrows from southern Spain (Huelva) was 3.2%, ranging from 2.8% in 2013 to 3.5% in 2014 (Fig 1). Using the 1,866 first captures of house sparrows with known sex and age, no differences in prevalence were found between years (F1,14 = 0.39, p = 0.54), nor months (F4,25 = 0.89, p = 0.49). Prevalence was also similar in urban, agricultural and natural habitats (F2,12 = 0.30, p = 0.75), and did not differ between males and females (F1,14 = 0.30, p = 0.60). However, the prevalence of APV lesions in southern Spain was higher in yearling birds (F1,14 = 20.57, p = 0.0005).