Bowen E T, Platt G S, Lloyd G, Raymond R T, Simpson D I
J Med Virol. 1980;6(2):129-38. doi: 10.1002/jmv.1890060205.
During the 1976 Ebola virus outbreak in Sudan, the investigations team gained the impression that fewer haemorrhagic manifestations and few fatalities occurred during the later stages of the epidemic after the virus had undergone several generations in man. This impression was also noted in guinea pigs experimentally infected with Sudanese and Zairean strains of Ebola virus. The virulence of the Sudanese isolates was less intense than isolates emanating from Zaire. Similar findings were seen in monkeys; a Zairean isolated produced fatal infections, whereas monkeys inoculated with a Sudan strain generally recovered. Two monkeys, which had recovered from Sudanese strain infections and had developed high levels of antibody detectable by immunofluorescence, were challenged with the Zairean strain. Both developed viraemias and died. The mechanisms of this "failed protection" are discussed.
在1976年苏丹埃博拉病毒爆发期间，调查团队有这样一种印象：在病毒在人类中历经数代传播后的疫情后期，出血症状较少且死亡病例也较少。在实验感染了苏丹和扎伊尔埃博拉病毒株的豚鼠身上也观察到了这种现象。苏丹分离株的毒力不如扎伊尔分离株强。在猴子身上也有类似的发现；一种扎伊尔分离株会导致致命感染，而接种苏丹毒株的猴子通常会康复。两只从苏丹毒株感染中康复且通过免疫荧光检测出高水平抗体的猴子，受到了扎伊尔毒株的攻击。两只猴子都出现了病毒血症并死亡。本文讨论了这种“保护失败”的机制。
