Baron R C, McCormick J B, Zubeir O A
Bull World Health Organ. 1983;61(6):997-1003.
Between 31 July and 6 October 1979, 34 cases of Ebola virus disease (22 of which were fatal) occurred among five families in a rural district of southern Sudan; the disease was introduced into four of the families from a local hospital. Chains of secondary spread within the family units, accounting for 29 cases resulted from direct physical contact with an infected person. Among all persons with such contact in the family setting, those who provided nursing care had a 5.1-fold increased risk of infection, emphasizing the importance of intimate contact in the spread of this disease. The absence of illness among persons who were exposed to cases in confined spaces, but without physical contact, confirmed previous impressions that there is no risk of airborne transmission. While the ecology of Ebola virus is unknown, the presence of anti-Ebola antibodies in the sera of 18% of persons who were unassociated with the outbreak suggests that the region is an endemic focus of Ebola virus activity.
1979年7月31日至10月6日期间，苏丹南部一个农村地区的五个家庭中出现了34例埃博拉病毒病（其中22例死亡）；该疾病从当地一家医院传入了四个家庭。家庭单位内的二代传播链导致了29例病例，这些病例是由于与感染者直接身体接触所致。在家庭环境中所有有此类接触的人中，提供护理的人感染风险增加了5.1倍，这凸显了密切接触在该疾病传播中的重要性。在密闭空间中接触病例但无身体接触的人未患病，这证实了之前的观点，即不存在空气传播风险。虽然埃博拉病毒的生态情况尚不清楚，但在与此次疫情无关的18%的人的血清中存在抗埃博拉抗体，这表明该地区是埃博拉病毒活动的地方性疫源地。
