Is the tuberculosis knowledge awareness obstructing tuberculosis infection in rural areas of Anqing, China?

Background Health education on tuberculosis is considered as one of the major measures for prevention of tuberculosis disease epidemic. This study is to assess the effects of tuberculosis awareness on tuberculosis infection in rural areas in China. Methods This study was conducted in rural areas of Anhui province, China. There 1118 newly diagnosed TB patients were selected as case group while 384 participants with no TB disease enrolled in control group. Univariate analysis and Multivariable logistic regression model were carried out to assess the effect of TB awareness on TB infection. Results The univariate analysis showed that four core knowledge items of TB, sex, age, education, domicile, smoking, drinking, income, contacting with TB patients, vaccination of bacillus calmette guerin and living area on TB were significantly different between the case and control groups ( P < 0.05). The multivariate logistic regression analysis revealed that education ( OR = 0.242, P = 0.001), income ( OR = 0.555, P = 0.016) were protective factors and domicile ( OR = 0.073, P = 0.026), contacting with TB patients ( OR = 3.020 , P = 0.017) were risk factors for TB infection. However, the awareness or any item of knowledge of TB were not found to be related to TB infection.


Abstract Background
Health education on tuberculosis is considered as one of the major measures for prevention of tuberculosis disease epidemic. This study is to assess the effects of tuberculosis awareness on tuberculosis infection in rural areas in China.

Methods
This study was conducted in rural areas of Anhui province, China. There 1118 newly diagnosed TB patients were selected as case group while 384 participants with no TB disease enrolled in control group. Univariate analysis and Multivariable logistic regression model were carried out to assess the effect of TB awareness on TB infection.

Results
The univariate analysis showed that four core knowledge items of TB, sex, age, education, domicile, smoking, drinking, income, contacting with TB patients, vaccination of bacillus calmette guerin and living area on TB were significantly different between the case and control groups (P < 0.05). The multivariate logistic regression analysis revealed that education (OR = 0.242, P = 0.001), income (OR = 0.555, P = 0.016) were protective factors and domicile (OR = 0.073, P = 0.026), contacting with TB patients (OR = 3.020, P = 0.017) were risk factors for TB infection. However, the awareness or any item of knowledge of TB were not found to be related to TB infection.

Conclusions
The awareness of TB is not the main influencing factor for TB infection in rural areas, the contents or forms of health education towards TB maybe modified in rural areas.

Background
Tuberculosis is a serious communicable disease around the world. In 2015, about 10.4 million people developed TB and 1.4 million died from this disease 1 . Current studies revealed that gender and age, degree of education, smoking, contact with TB patients, income level, history of BCG vaccination and infection with HIV were probably associated to TB infection 2-8 . In addition to those factors, the lack of awareness about TB was considered to be the most important factor that increased the risk of exposure to TB 9 . Especially, loss of knowledge on the cause, mode of transmission, and symptoms as well as irregular treatment of TB would pose a great challenge to control the disease 10-13 .
Furthermore, poor awareness of TB was also an influencing factor of MDR-TB 14 .
Unfortunately, the awareness of TB was found to be very poor, especially in rural areas 15,16 . Study from Sudan manifested that there was no significant difference of awareness about TB between TB cases and controls 17 . As a consequence, in order to provide a scientific basis for TB prevention, we conducted this case-control study to assess the effects of awareness on TB infection and explore influencing factors for TB infection in Anqing area.

Study participants and sampling
This study was carried out between June 2014 and December 2015 in Anqing area. The study site was located in typical rural area of central China and in the southwest of Anhui province with relatively high prevalence of TB and the majority of the population were from rural areas with much lower economic level. Therefore, this area is well representing TB epidemic in rural areas of China. A total of 1502 participants were selected in the communities from eight counties, newly diagnosed TB patients were enrolled in the case group, and healthy controls was recruited randomly within the neighborhood or the household of the TB case. The diagnosis are strictly based on laboratory inspections such as chest X-ray examination, sputum smear examination and clinical symptoms. All participants were informed about the objectives of the study and provided verbal informed consent before the survey. Newly detected sputum smear positive pulmonary TB patients > 15 years who had presented at local medical institutions were eligible for inclusion. People who refused to participate or worked in other city were excluded. The study population was finally gathered on the basis of 1118 cases and 384 controls.
We defined cases as adults (aged 15 years and older) with sputum smear positive pulmonary TB.
They were interviewed immediately after diagnosis. Those who did not have a sputum smear confirmed diagnosis were excluded from the study. We selected controls randomly that had a sputum smear negative TB from the database. All cases and the controls came from the same source population in this study.

Study Design And Data Collection
The data collection tool was a unified self-administered questionnaire which was designed according to the World Health Organization guidelines 18 , and then it was pre-tested among 100 people who did not participate in the study and was modified as necessary. Participants were interviewed face-to-face by investigators who had medical science background from local Centers for Disease Control and Prevention (CDC). All information about cases was inquired before their suffering from TB disease.
The questionnaire consists of questions on demographic and socioeconomic characteristics (sex, age, education, domicile, smoking-alcohol abuse, other respiratory system medical history, contact with TB patients, history of BCG vaccination, income and living space) of the study participants and their awareness of TB. The awareness section contained 6 questions (details in Table 1). control groups (P < 0.001) and details have been presented in Table 2.  Table 1 showed that questions of "What is the main pathogen causing tuberculosis", "What is the cardinal symptom of TB patients", "What is the source of infection of tuberculosis" and "What is the route of transmission of tuberculosis" differed significantly compared with control group (P < 0.05);

Univariate Analysis Of Knowledge Awareness On Tb Infection
While there were no significant differences at the questions of "Do you know relevant information about tuberculosis" and "Is tuberculosis a contagious disease" compared with the control group.    29,30 . The risk of TB increased progressively with age in the case group 31 , probably because of low immune level among aged. We found that the risk of TB in cases with higher education background were much lower than those with less education, in another words, high degree of education was the protective factor of TB 29 , it may be because higher-educated people know how to protect themselves better. Findings from some studies 32-34 revealed that smoking was independently associated with TB, which was consistent with our findings. Our results were in line with previous studies 35 in that a higher income was consistently associated with reduced TB risk. It is likely that people with higher income will have higher medical assurance level. Authors' contributions YFZ analyzed and interpreted the data, drafted and revised the manuscript. YFW conceived and designed the study, participated in data collection and critically reviewed the manuscript. ZPZ, HW, XMW, CXW, and HX participated in data collection and reviewed the manuscript. All authors read and approved the final manuscript version for publication.