Fox Gregory J, Orlova Marianna, Schurr Erwin
McGill International TB Centre, McGill University, Montreal, Quebec, Canada.
Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute, Montreal, Quebec, Canada.
PLoS Pathog. 2016 Jan 21;12(1):e1005271. doi: 10.1371/journal.ppat.1005271. eCollection 2016 Jan.
In an accident later known as the Lübeck disaster, 251 neonates were orally given three doses of the new Bacille Calmette-Guérin (BCG) antituberculosis (TB) vaccine contaminated with Mycobacterium tuberculosis. A total of 173 infants developed clinical or radiological signs of TB but survived the infection, while 72 died from TB. While some blamed the accident on BCG itself by postulating reversion to full virulence, such a possibility was conclusively disproven. Rather, by combining clinical, microbiological, and epidemiological data, the chief public health investigator Dr. A. Moegling concluded that the BCG vaccine had been contaminated with variable amounts of fully virulent M. tuberculosis. Here, we summarize the conclusions drawn by Moegling and point out three lessons that can be learned. First, while mortality was high (approximately 29%), the majority of neonates inoculated with M. tuberculosis eventually overcame TB disease. This shows the high constitutional resistance of humans to the bacillus. Second, four semiquantitative levels of contamination were deduced by Moegling from the available data. While at low levels of M. tuberculosis there was a large spread of clinical phenotypes reflecting a good degree of innate resistance to TB, at the highest dose, the majority of neonates were highly susceptible to TB. This shows the dominating role of dose for innate resistance to TB. Third, two infants inoculated with the lowest dose nevertheless died of TB, and their median time from inoculation to death was substantially shorter than for those who died after inoculation with higher doses. This suggests that infants who developed disease after low dose inoculation are those who are most susceptible to the disease. We discuss some implications of these lessons for current study of genetic susceptibility to TB.
在一场后来被称为吕贝克灾难的事故中,251名新生儿口服了三剂被结核分枝杆菌污染的新型卡介苗(BCG)抗结核疫苗。共有173名婴儿出现了结核病的临床或放射学症状,但感染后存活下来,而72名婴儿死于结核病。虽然有些人通过假设卡介苗恢复了完全毒力而将事故归咎于卡介苗本身,但这种可能性已被确凿地否定。相反,通过综合临床、微生物学和流行病学数据,首席公共卫生调查员A. 默格林博士得出结论,卡介苗疫苗已被不同数量的完全毒力结核分枝杆菌污染。在此,我们总结默格林得出的结论,并指出可以吸取的三个教训。首先,虽然死亡率很高(约29%),但大多数接种结核分枝杆菌的新生儿最终战胜了结核病。这表明人类对这种杆菌具有很高的固有抵抗力。其次,默格林从现有数据中推断出了四个半定量的污染水平。虽然在低水平的结核分枝杆菌污染时,临床表型有很大差异,反映出对结核病有一定程度的固有抵抗力,但在最高剂量时,大多数新生儿对结核病高度易感。这表明剂量在对结核病的固有抵抗力中起主导作用。第三,两名接种最低剂量疫苗的婴儿仍然死于结核病,他们从接种到死亡的中位时间比接种较高剂量疫苗后死亡的婴儿要短得多。这表明低剂量接种后发病的婴儿是最易患该病的婴儿。我们讨论了这些教训对当前结核病遗传易感性研究的一些启示。