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1. Disease epizootics can significantly influence host population dynamics and the structure\udand functioning of ecological communities. Sarcoptic mange Sarcoptes scabiei has dramatically\udreduced red fox populations Vulpes vulpes in several countries, including Britain,\udalthough impacts on demographic processes are poorly understood. We review the literature\udon the impact of mange on red fox populations, assess its current distribution in Britain\udthrough a questionnaire survey and present new data on resultant demographic changes in\udfoxes in Bristol, UK.\ud\ud2. A mange epizootic in Sweden spread across the entire country in < 10 years resulting in a\uddecline in fox density of up to 95%; density remained lowered for 15–20 years. In Spain,\udmange has been enzootic for > 75 years and is widely distributed; mange presence was\udnegatively correlated with habitat quality.\ud\ud3. Localized outbreaks have occurred sporadically in Britain during the last 100 years. The\udmost recent large-scale outbreak arose in the 1990s, although mange has been present in\udsouth London and surrounding environs since the 1940s. The questionnaire survey indicated\udthat mange was broadly distributed across Britain, but areas of perceived high prevalence\ud(> 50% affected) were mainly in central and southern England. Habitat type did not significantly\udaffect the presence/absence of mange or perceived prevalence rates. Subjective assessments\udsuggested that populations take 15–20 years to recover.\ud\ud4. Mange appeared in Bristol’s foxes in 1994. During the epizootic phase (1994–95), mange\udspread through the city at a rate of 0.6–0.9 km/month, with a rise in infection in domestic\uddogs Canis familiaris c. 1–2 months later. Juvenile and adult fox mortality increased and the\udproportion of females that reproduced declined but litter size was unaffected. Population\uddensity declined by > 95%.\ud\ud5. In the enzootic phase (1996–present), mange was the most significant mortality factor.\udJuvenile mortality was significantly higher than in the pre-mange period, and the number of\udjuveniles classified as dispersers declined. Mange infection reduced the reproductive potential\udof males and females: females with advanced mange did not breed; severely infected males\udfailed to undergo spermatogenesis. In 2004, Bristol fox population density was only 15% of\udthat in 1994