Children With Severe Tuberculosis Influencing Factors And The Effect Of Bcg Vaccine Against

BackgroundTuberculosis is an important worldwide public health problem. It is one of the major controlled diseases. Chinese Epidemic Tuberculos showed new features, such as high prevalence rate, high drug resistance rate, large number of death, high epidemic among the young and middle-aged population, combined HIV infection, and migrant population. Bacillus Calmette-Guerin (BCG) is one of the world's most widely used vaccine, that is one of measures to TB control. The exact effect about BCG protection against tuberculosis is divergent debate. Experts and scholars generally agreed that BCG vaccination can not prevent from getting pulmonary tuberculosis, but it has effect to prevent against severe tuberculosis throught hematogenous disseminated tuberculosis, such as meningitis and miliary tuberculosis. The research on BCG protecting against TB meiningitis is limited in China. The protection of the BCG against tuberculous meningitis and other severe effect is still inconsistent. With the emergence of the new situation, In some countries with low burden of disease (such as the United States, Sweden), only administered vaccine to the high rish group, including newborns, infants , children with skin test negative and older children. The people living in the lower disease burden of TB disease has implemented the strategy of strengthening surveillance and early treatment instead of administering BCG vaccine. It is necessary to conduct a study to explore if CHINA implement the existed BCG immunization strategy For the severe tuberculosis , such as childhood tuberculous meningitis control and prevention.ObjectiveTo understand the risk factors for children severe tuberculosis, understand the effect of BCG prevention against chindren severe tuberculosis, and provide data to improve or update the existed BCG immunization strategy for chindren severe tuberculosis control and prevention.MethodsCommunity-based case-control study method was used. Severe tuberculosis, such as tuberculous meningitis patients were selected according to the age , sex, hometowm. Appropriate control group, which based on 1:3 proportion, were selected as well. Survey was conducted by questionnaire. Using chi-square test, the single factor and multiple factors logistic regression to analysis the data by Epiinfo software. The rate of vaccine protection was calculated by the formula of "vaccine effectiveness (VE)=(1-OR)*100" .ResultsTotal 42 cases of tuberculous meningitis cases were surveyed. Among them, 13 cases combine miliary tuberculosis. 126 person involved in the control group. The size of the family situation, the income of families , the living space of family , the residential status, history of chronic diseases don't has statistic difference between two groups. Contacting with tuberculosis patients ( x²=18.1668, P=0.0001) , the relationship between the people who have a history of exposure to tuberculosis patients (x²=48.0535, P=0.0000) , the degree of contact with tuberculosis patients (x²=47.4479, P=0.0000) , History of tuberculosis (x²=42.8406 P=0.0000), BCG vaccination(x²=25.4873 P=0.0000) has statistic significances. BCG's VE is 89. 42%, 95%CI is 69%～97%. The regression model is as follow: logit(P)=1.4611X₁₅+2.8620X₁₉-4.8094 X_{201 11}ConclusionsThe factors, including size of the family, the family total income, the total household living area, place of residence status, residential status, history of chronic diseases had not statistic association with children sever TB. The history of exposure to tuberculosis patients, close contacts of tuberculosis patients and the extent of contact were the risk factors for children's sever tuberculosis, including TB meningitis. BCG vaccination is a protective factor for children severe tuberculosis. The protection rate of BCG was 89.24%, 95% CI for (69%, 97%).The TB patients should be found actively. The patients with pulmonary tuberculosis should be treated and managed. Neonatal BCG vaccination strategy will be implemented continuously. The research and development of new BCG vaccine is necessary for the children's sever tuberculosis control and prevention.