Abstract: Objective To observe the epidemiological effect and safety on Mycobacterium vaccae (M. vaccae)for prevention pulmonary tuberculosis. Methods According to the PPD skin test results, double-blind controlled prospective study were conducted in the new students of primary school, middle school and college. All students were randomly divided into experimental group(21 684 cases vaccinated with M. vaccae) and control group(21 421 cases vaccinated with hepatitis B vaccine)。The morbidity of pulmonary tuberculosis and allergic diseases were followed up for 3 years approved by the Ethics Committee of our centre. Results The incidence rate of pulmonary tuberculosis in experimental group and in control group were 0.14‰ and 0.51‰, respectively (χ²=4.671，P=0.031）.The incidence rate of allergic asthma in experimental group and in control group were 0.46‰ and 1.31‰, respectively.(χ²=8.755，P=0.003). The incidence rate of allergic skin diseases in experimental group and in control group were 3.04 ‰ and 4.29‰, respectively. (χ²=4.619，P=0.032). All differences above were significant statistically. However, the incidence of fever were not significant statistically (u=1.71,P<0.05) in experimental group with 6.69‰ (151/21684) and in control group with 2.75‰ (59/21 421). Conclusion M. vaccae has good epidemiological effect on the prevention of pulmonary tuberculosis, allergic asthma and allergic skin diseases M. vaccae is also safe for injection.

Key words: Tuberculosis, pulmonary/prevention and control, Mycobacterium vaccae vaccine, prospective study