Table 1 The demographic characteristics of the total study population:

1. clinical symptom of pulmonary TB

1. very close TB contacts recently that live together

1. healthy, BCG-vaccinated controls;

2. positive acid-fast bacilli in sputum smears or positive mycobacteria culturing or a suggestive chest X-ray

with TB patient

2. positive of T SPOT. TB test

2. no prior M.TB contact or exposure

3. (for T-cell tests only ) received DOTS therapy less then 1 month

3. no clinical symptom, nor abnormal chest radiograph

117

45

67

46.4

45.1

34.9

6-84

16-76

21-68

85/32

13/32

32/35

56

20

30

46.5

43.6

29.6

11-81

23-74

21-58

35/21

4/16

13/17