More than 23 years of warfare in Afghanistan has caused over 6 million Afghans to seek asylum in approximately 70 different countries, with most Afghan refugees settling in the developing countries of Pakistan and Iran. In a developing host country, poor sanitation and nutrition, overcrowding and inaccessibility to health care facilities act synergistically to influence morbidity and mortality from infectious disease in the refugee population. In this Science and Society article we discuss the prevalence of transmissible infection, modes of transmission, associated risk factors, and the state of health and health care in the displaced Afghan population.