Storla Dag Gundersen, Kristiansen Ingun, Oftung Fredrik, Korsvold Gro Ellen, Gaupset Monica, Gran Gerd, Øverby Anne Kristin, Dyrhol-Riise Anne Margarita, Bjune Gunnar Aksel
Department of International Health, Institute of General Practice and Community Medicine, University of Oslo, Oslo, Norway.
BMC Infect Dis. 2009 May 11;9:60. doi: 10.1186/1471-2334-9-60.
We intended to assess the risk for health care workers (HCWs) of acquiring M. tuberculosis infection after exposure to patients with sputum-smear positive pulmonary tuberculosis at three University Hospitals (Ullevål, Akershus, and Haukeland) in Norway.
We tested 155 exposed health care workers and 48 healthy controls both with a tuberculin skin test (Mantoux) and the T-SPOT.TB test, a recently developed interferon-gamma release assays based on the M. tuberculosis-specific ESAT-6 and CFP10 antigens, to investigate if this test might improve infection control measures.
Among the 155 exposed HCWs tested in this study, 27 individuals were defined as newly infected cases by TST after recent exposure, while only 3 of these had a positive T-SPOT.TB test. The number of T-SPOT.TB positives represents 11% of the individuals defined as recently infected by TST after exposure (3/27) and 2% of the total number of exposed people tested (3/155). In addition, 15 individuals had been previously defined as infected by TST before exposure of whom 2 subjects were T-SPOT.TB positive. All individuals detected as T-SPOT.TB positive belonged to the TST positive group (> 15 mm), and the percentage concordance between T-SPOT.TB and TST, including both previously and newly infected subjects, was 12% (5/42). The 48 control participants used in the study were all T-SPOT.TB negative, but 3 of these subjects were TST positive.
Our data indicate that the frequency of latent TB in the total cohort of HCWs is 3%, whereas the rate of transmission of TB to exposed individuals is approximately 2% and occurs through exposure periods of short duration. Thus, the risk of TB transmission to HCWs following TB exposure in a hospital setting in Norway is low, and improved screening approaches will benefit from the application of specific interferon-gamma release assays.
我们旨在评估挪威三家大学医院（乌勒瓦尔、阿克什胡斯和豪克兰）中，医护人员在接触痰涂片阳性肺结核患者后感染结核分枝杆菌的风险。
我们对155名暴露的医护人员和48名健康对照者进行了结核菌素皮肤试验（曼托试验）和T-SPOT.TB试验（一种基于结核分枝杆菌特异性ESAT-6和CFP10抗原的新型干扰素-γ释放试验），以研究该试验是否能改善感染控制措施。
在本研究中检测的155名暴露医护人员中，27人在近期暴露后通过结核菌素皮肤试验被定义为新感染病例，而其中只有3人的T-SPOT.TB试验呈阳性。T-SPOT.TB试验阳性的人数占暴露后通过结核菌素皮肤试验被定义为近期感染的个体的11%（3/27），占接受检测的暴露人群总数的2%（3/155）。此外，有15人在暴露前曾被结核菌素皮肤试验定义为感染，其中2名受试者T-SPOT.TB试验呈阳性。所有检测为T-SPOT.TB试验阳性的个体均属于结核菌素皮肤试验阳性组（>15mm），包括既往感染和新感染受试者在内，T-SPOT.TB试验与结核菌素皮肤试验的一致性百分比为12%（5/42）。本研究中使用的48名对照参与者T-SPOT.TB试验均为阴性，但其中3名受试者结核菌素皮肤试验呈阳性。
我们的数据表明，医护人员总队列中潜伏性结核的发生率为3%，而结核分枝杆菌向暴露个体的传播率约为2%，且发生在短时间暴露期间。因此，在挪威医院环境中，医护人员接触结核病后感染结核病的风险较低，应用特定的干扰素-γ释放试验将有助于改进筛查方法。
