Latent tuberculosis infection status and influence factors analysis on student close contacts with tuberculosis among universities and technical secondary schools in Pudong New Area of Shanghai

ObjectiveTo investigate the situation and the major influencing factors of latent tuberculosis infection(LTBI) in student close contacts with pulmonary TB patients among universities and technical secondary schools in Pudong New Area in Shanghai.

MethodsA total of 479 student close contacts with pulmonary TB patients among universities and technical secondary schools were involved in this study in Pudong New Area in Shanghai from Jan 1, 2017 to Dec 31, 2017.The Quanti FERON-TB Gold test(QFT) was conducted to identify the LTBI and questionnaire was applied to collect the information of gender, age, household registration and duration of exposure and so on.Single and multivariate analysis were conducted to identify the major influencing factors of LTBI.

ResultsThe mean age of student close contacts was (20.8±1.4) years.The QFT revealed that 47 student close contacts were latently infected with TB.According to the degree of close contact, the QFT positive rate of roommates and contacts on the same floor dormitory meanwhile in the same class was significantly higher than that of the general contacts.In multivariate analysis, the risk of LTBI was statistically associated with the gender of male(OR=3.72, 95%CI:1.06~12.99) and cumulative duration of exposure over 80 hours (OR=3.33, 95%CI:1.12~9.86).

ConclusionRoommates and contacts on the same floor dormitory and in the same class are at a high risk on LTBI.Gender of male and cumulative duration of exposure over 80 hours might increase the risk of LTBI.Early screening of LTBI among student close contacts with TB patients should be enhanced on the basis of existing school TB control and intervening measures should be provided to infected persons as early as possible.