Prevalent and incident latent tuberculosis infection among healthcare workers in Taiwan: A multi-center observational study.

BACKGROUND

Healthcare workers (HCWs) have increased risks of active tuberculosis, yet there are limited reports of incidence and risk factors of latent tuberculosis infection (LTBI) among HCWs.

METHODS

HCWs were enrolled from four medical centers in Taiwan. Quantiferon-TB Gold Plus Test (QFT-Plus) was performed initially and 9-12 months afterwards. The prevalence, incidence, and clinical factors associated with LTBI, and willingness to receive LTBI treatment were explored.

RESULTS

Among 297 HCWs, the prevalence rate of LTBI was 10.8 %. The independent factors associated with prevalent LTBI were age >40 years old (aOR 3.52, 95 % CI 1.46-8.45), health professionals (aOR 3.99, 95 % CI 1.02-15.65), and working in intensive care units (ICUs) (aOR 4.06, 95 % CI 1.28-12.86). Having all three factors escalated the risk of prevalent LTBI (aOR 13.81, 95 % CI 3.16-60.37). Of 129 LTBI-free HCWs undergoing 2nd QFT-Plus, seven (5.4 %) had positive conversion, indicating incident LTBI, among which four had TB contacts without wearing N95 mask. Two had a TB2-TB1 value > 0.6 IU/ml. 40.6 % prevalent LTBI patients refused LTBI preventive therapy.

CONCLUSIONS

More advanced age, health professionals, and working in ICUs were independent factors associated with prevalent LTBI. Most healthcare workers with incident LTBI cases had TB contacts without wearing N95 masks.