Rhinocerebral mucormycosis is a rare disease, affecting almost exclusively patients with known predisposing conditions such as diabetes mellitus, immunocompromised status, haemochromatosis or major trauma. Subsequent to a case of rhinocerebral mucormycosis in a 78-year-old woman without any known risk factor, we reviewed the published English-language literature and found an additional 72 cases. Reviewing all the published case series of mucormycosis involving any site, the proportion of apparently normal hosts among cases of rhinocerebral mucormycosis was found to be 9.06% (95% confidence interval 6.7-11.8). These findings suggest that rhinocerebral mucormycosis in patients without known predisposing factors is more prevalent than was previously believed.