[Molecular epidemical characteristics of Mycobacterium tuberculosis strains from the nationwide random survey for the epidemiology of tuberculosis in China, 2000].
OBJECTIVE
To explore the epidemical distribution characteristics of Mycobacterium tuberculosis isolated from China.


METHODS
The M. tuberculosis strains were gained by multi-stratified grouping random sampling method from the nationwide random survey for the epidemiology of tuberculosis in China, 2000, and analyzed by IS6110-based RFLP and DR-based Spoligotyping DNA fingerprinting. These fingerprinting patterns were transferred into digital data and compared each other, and clustered by Gel compar4.1 Software. The clustering values in different TB patients were compared by chi(2) test and the risk factors for recent transmission were calculated by Odd Ratios.


RESULTS
Two hundreds and four of 402 M. tuberculosis strains from this survey were determined to be "Beijing Genotype" M. Tuberculosis strain by DNA fingerprinting analysis. Three clusters M. tuberculosis strains sharing identical fingerprint pattern were found, including one cluster belong to a same family. There were significant difference between female and male, and younger (< 40 years old) and elder (>or= 40 years old) (P < 0.05). Odds Ratio 1 showed youth [1.68 95% CI (1.01 - 2.80)] and male [2.04 95% CI (1.07 - 3.96)], but Odds Ratio 2 showed youth [0.3 95% CI (0.2 - 0.44)] and male [4.96 95% CI (2.77 - 9.00)].


CONCLUSIONS
M. tuberculosis strains of Beijing Genotype are prevailing in China at present. Male and elder were shown to be significant risk factors for recent transmission. The infection source of M. tuberculosis could be traced by DNA fingerprinting.
Li
Wei-min
WM
Department of Bacteriology and Immunology, Beijing Tuberculosis and Chest Tumor Institution, Beijing 101149, China.
Duanmu
Hong-jin
HJ
Wang
Li-xia
LX
Ding
Bei-chuan
BC
Liu
Yu-hong
YH
Li
Chuan-you
CY
Fu
Yu
Y
D000328:Adult; D002681:China / Q000453:epidemiology; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008403:Mass Screening; D017720:Molecular Epidemiology; D009169:Mycobacterium tuberculosis / Q000235:genetics*; D012307:Risk Factors; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission
D004269:DNA, Bacterial