Abstract
Background: Tuberculin skin test (TST) has been the most commonly used test for diagnosis of tuberculosis (TB) infection in China for many years, because of well-established algorithms for test interpretation and a good cost-effectiveness. To our knowledge , there is no report or guideline on the influence of varicella vaccine on the sensitivity of TST in China. This paper aims to explore the effect of live attenuated varicella vaccine on the sensitivity of TST.Methods: A retrospective cohort study was carried out in a high school in Wuxi, Jiangsu province in 2020. TST and emergency varicella vaccine were administered to students in grade one of the high school which had both TB and varicella cases. The mean diameter of induration of TST were compared between 73d before varicella vaccine, 9d and 120d after varicella vaccine respectively. The retrospective cohort study was used to analyze the effect of live attenuated varicella vaccine on TST.Results: There were 45 students in the class of the high school had three TST, and 22 of them were vaccinated varicella. After 9 days of varicella vaccination, the mean diameter of induration was significantly smaller than that before the vaccination of 73 days and after the vaccination of 120 days (p<0.05), respectively. Moreover, there is no significant different for mean diameter of induration between the TST before the vaccination of 73 days and after the vaccination of 120 days (p=0.551). The retrospective cohort study analysis indicated that 9 days after varicella vaccination ( RR, 6.071, 95%CI, 1.667～22.116, P=0.007 ) was associated with the changed mean induration diameter of TST. After vaccination of 120 days ( RR, 3.474, 95%CI, 0.333～36.240, P=0.346 ) was not associated with the changed mean induration of TST.Conclusions: Live attenuated varicella vaccine may temporarily affect the sensitivity of tuberculin skin test.
Risk for Tuberculosis Disease Among Contacts with Prior Positive Tuberculin Skin Test: A retrospective Cohort Study, New York City
