A tuberculosis outbreak among senior high school students in China in 2011

The necessity for enhancing awareness of tuberculosis starting from the early college semesters: empirical evidence from a cross-sectional research

Background

College students, especially those in the lower grades, constitute the main high-risk population for tuberculosis (TB). Insufficient knowledge about TB among college students contributes to an increased risk of TB infection. In Zhejiang Province, China, limited research has been conducted recently on the awareness of TB in schools among college students. Therefore, this study aims to gain insight into TB knowledge among low-grade college students in Zhejiang Province and develop effective strategies for TB education targeted at this specific population.

Methods

A cross-sectional survey was conducted between 1st and 20th May 2022 in 20 colleges in Zhejiang Province, southeastern China. The survey aimed to assess the level of TB awareness among 1st and 2nd-year college students. Chi-square tests were performed to compare the rates, while multivariate logistic regression was used to identify the factors influencing the overall awareness level of students' regarding key knowledge about TB.

Results

A total of 4,414 lower-grade students participated in the study. The total awareness rate and entire awareness rate of key TB knowledge were 81.6 and 25.3%, respectively. Participants who demonstrated a relatively poor understanding of the definition were (51.0%), curable outcomes (75.7%), and preventive measures of TB (76.1%). Female participants [adjusted odds ratio (aOR):1.44; 95% confidence interval (CI):1.25-1.65], medical students (aOR:2.00; 95%CI:1.63-2.64), had a high level of monthly expenditures (aOR:2.50; 95%CI:1.49-4.19), had prior TB health education (aOR:1.95; 95%CI:1.68-2.25) and previous exposure to TB patients (aOR:2.13; 95% CI:1.48-3.08) indicating a better level of awareness of key knowledge about TB. Among the students, 58.5% expressed their willingness to acquire TB knowledge through "broadcasting, television, films, and audiovisual materials."

Conclusions

The total awareness rate of key knowledge among low-grade college students in Zhejiang did not meet the national requirements. To effectively prevent TB in schools, it is crucial to develop a comprehensive understanding of the disease among college students. Therefore, it is necessary to enhance TB awareness through theoretical and practical education, starting from the early semesters of college.

Whole-Genome Sequencing and Epidemiological Investigation of Tuberculosis Outbreaks in High Schools in Hunan, China

Background

Tuberculosis (TB) seriously threatens individual and public health. Recently, TB outbreaks in schools have been reported more frequently in China and have attracted widespread attention. We reported three TB outbreaks in high schools in Hunan Province, China.

Methods

When a tuberculosis patient was reported in a school, we carried out field epidemiological investigations, including tuberculin skin testing (TST), chest X-ray (CXR) and laboratory test for all close contacts, and whole-genome sequencing (WGS) analyses to understand the transmission patterns, the causes and the risk factors for the outbreaks, thereby providing a foundation for the control of TB epidemics in schools.

Results

A total of 49 students with TB patients were identified in the three schools where TB outbreaks occurred, including nine patients in School A, 14 patients in School B, and 26 patients in School C. In Schools A, B and C, the putative attack rates in the classes of the index case were 13.8% (8/58), 7.6% (5/66), and 40.4% (21/52), while the putative attack rates of expanding screening in the school were 0.3% (1/361), 0.2% (9/3955), and 0.2% (5/2080), respectively. Thirteen patients had patient delay, with a median delay interval of 69 days (IQR 30.5–113 days). Twelve patients had a healthcare diagnostic delay with a median delay interval of 32 days (IQR 24–82 days). Phylogenetic analysis of culture-positive patients revealed that most of them shared a small genetic distance (≤12 SNPs), with three separate genetic clusters (including one MDR-TB genomic cluster), indicating the recent transmission of Mycobacterium tuberculosis strains.

Conclusion

This combination of field investigation and WGS analysis revealed the transmission of three TB outbreaks in schools. Reinforced implementation is needed to improve timely case finding and reduce diagnosis delay in routine TB control in the school population.

Symptom- and chest-radiography screening for active pulmonary tuberculosis in HIV-negative adults and adults with unknown HIV status

BACKGROUND

Systematic screening in high-burden settings is recommended as a strategy for early detection of pulmonary tuberculosis disease, reducing mortality, morbidity and transmission, and improving equity in access to care. Questioning for symptoms and chest radiography (CXR) have historically been the most widely available tools to screen for tuberculosis disease. Their accuracy is important for the design of tuberculosis screening programmes and determines, in combination with the accuracy of confirmatory diagnostic tests, the yield of a screening programme and the burden on individuals and the health service.

OBJECTIVES

To assess the sensitivity and specificity of questioning for the presence of one or more tuberculosis symptoms or symptom combinations, CXR, and combinations of these as screening tools for detecting bacteriologically confirmed pulmonary tuberculosis disease in HIV-negative adults and adults with unknown HIV status who are considered eligible for systematic screening for tuberculosis disease. Second, to investigate sources of heterogeneity, especially in relation to regional, epidemiological, and demographic characteristics of the study populations.

SEARCH METHODS

We searched the MEDLINE, Embase, LILACS, and HTA (Health Technology Assessment) databases using pre-specified search terms and consulted experts for unpublished reports, for the period 1992 to 2018. The search date was 10 December 2018. This search was repeated on 2 July 2021.

SELECTION CRITERIA

Studies were eligible if participants were screened for tuberculosis disease using symptom questions, or abnormalities on CXR, or both, and were offered confirmatory testing with a reference standard. We included studies if diagnostic two-by-two tables could be generated for one or more index tests, even if not all participants were subjected to a microbacteriological reference standard. We excluded studies evaluating self-reporting of symptoms.

DATA COLLECTION AND ANALYSIS

We categorized symptom and CXR index tests according to commonly used definitions. We assessed the methodological quality of included studies using the QUADAS-2 instrument. We examined the forest plots and receiver operating characteristic plots visually for heterogeneity. We estimated summary sensitivities and specificities (and 95% confidence intervals (CI)) for each index test using bivariate random-effects methods. We analyzed potential sources of heterogeneity in a hierarchical mixed-model.

MAIN RESULTS

The electronic database search identified 9473 titles and abstracts. Through expert consultation, we identified 31 reports on national tuberculosis prevalence surveys as eligible (of which eight were already captured in the search of the electronic databases), and we identified 957 potentially relevant articles through reference checking. After removal of duplicates, we assessed 10,415 titles and abstracts, of which we identified 430 (4%) for full text review, whereafter we excluded 364 articles. In total, 66 articles provided data on 59 studies. We assessed the 2 July 2021 search results; seven studies were potentially eligible but would make no material difference to the review findings or grading of the evidence, and were not added in this edition of the review. We judged most studies at high risk of bias in one or more domains, most commonly because of incorporation bias and verification bias. We judged applicability concerns low in more than 80% of studies in all three domains. The three most common symptom index tests, cough for two or more weeks (41 studies), any cough (21 studies), and any tuberculosis symptom (29 studies), showed a summary sensitivity of 42.1% (95% CI 36.6% to 47.7%), 51.3% (95% CI 42.8% to 59.7%), and 70.6% (95% CI 61.7% to 78.2%, all very low-certainty evidence), and a specificity of 94.4% (95% CI 92.6% to 95.8%, high-certainty evidence), 87.6% (95% CI 81.6% to 91.8%, low-certainty evidence), and 65.1% (95% CI 53.3% to 75.4%, low-certainty evidence), respectively. The data on symptom index tests were more heterogenous than those for CXR. The studies on any tuberculosis symptom were the most heterogeneous, but had the lowest number of variables explaining this variation. Symptom index tests also showed regional variation. The summary sensitivity of any CXR abnormality (23 studies) was 94.7% (95% CI 92.2% to 96.4%, very low-certainty evidence) and 84.8% (95% CI 76.7% to 90.4%, low-certainty evidence) for CXR abnormalities suggestive of tuberculosis (19 studies), and specificity was 89.1% (95% CI 85.6% to 91.8%, low-certainty evidence) and 95.6% (95% CI 92.6% to 97.4%, high-certainty evidence), respectively. Sensitivity was more heterogenous than specificity, and could be explained by regional variation. The addition of cough for two or more weeks, whether to any (pulmonary) CXR abnormality or to CXR abnormalities suggestive of tuberculosis, resulted in a summary sensitivity and specificity of 99.2% (95% CI 96.8% to 99.8%) and 84.9% (95% CI 81.2% to 88.1%) (15 studies; certainty of evidence not assessed).

AUTHORS' CONCLUSIONS

The summary estimates of the symptom and CXR index tests may inform the choice of screening and diagnostic algorithms in any given setting or country where screening for tuberculosis is being implemented. The high sensitivity of CXR index tests, with or without symptom questions in parallel, suggests a high yield of persons with tuberculosis disease. However, additional considerations will determine the design of screening and diagnostic algorithms, such as the availability and accessibility of CXR facilities or the resources to fund them, and the need for more or fewer diagnostic tests to confirm the diagnosis (depending on screening test specificity), which also has resource implications. These review findings should be interpreted with caution due to methodological limitations in the included studies and regional variation in sensitivity and specificity. The sensitivity and specificity of an index test in a specific setting cannot be predicted with great precision due to heterogeneity. This should be borne in mind when planning for and implementing tuberculosis screening programmes.

Tuberculosis Outbreak in an Educational Institution in Henan Province, China

On June 17, 2018, a case of pulmonary tuberculosis (TB) was reported among students at a senior high school in Luoning, China. The outbreak encompassed a total of 23 cases along with TB screening in the whole school by means of PPD and chest X-ray. By the end of September 2018, the entire 9 cases cultured positive had epidemiological association. All of the 9 Mycobacterium tuberculosis (Mtb) isolates available were sensitive to all drugs tested and had similar spoligotyping and 15 loci mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) profile. Whole-genome sequencing (WGS) of the Mtb isolates revealed 20 variable nucleotide positions within 8 cases, indicating a clonal outbreak. The index case, which was first identified and diagnosed, is separated from the cluster by a minimum number of 95 distinct SNPs. Minimum distance spanning tree (MST) indicted that the 8 cases were indeed part of a single transmission chain. It was concluded that this is an epidemic situation of TB outbreak exposed by the aggrieved index case at school, which was caused by the veiled infectious case wherein a student was suffering from TB and attending school simultaneously.

Multidrug-resistant tuberculosis transmission among middle school students in Zhejiang Province, China

Background

Despite significant advancements in the treatment and diagnosis of tuberculosis (TB) over the past decade, drug-resistant TB remains an increasing threat to public health. TB outbreaks are most commonly reported in schools considering the delay in TB diagnosis, sustained contact, and overcrowding observed in schools. This report describes multidrug-resistant TB (MDR-TB) transmission in a school in Zhejiang Province. We aimed to raise awareness regarding MDR-TB transmission among students.

Case presentation

The index patient was a 16-year-old girl in the second year of junior middle school in Zhejiang Province, China, who had been experiencing persistent cough and expectoration for 37 days since 1 March 2014. She tested positive for smear pulmonary and extrapulmonary TB on 8 April 2014 and was subsequently diagnosed with MDR-TB on 1 May 2014. However, the patient was resistant to isoniazid, rifampicin, ethambutol, and streptomycin. Thus, she was suspended from school for anti-TB treatment. All 54 students who were in close contact with the index patient in the same class were screened, and 5 tested positive on the tuberculin skin test. Their exposure time to the index patient was approximately 37 days. Three classmates were subsequently diagnosed with MDR-TB, with similar resistance profiles nearly two years later. Their average discovery delay was 55 days. These three classmates were also suspended from school for anti-TB treatment. During the treatment period, four students visited the local TB-designated hospital for further consultation every month and were followed up once a month by the local community health service center until they were completely cured.

Conclusions

Discovery delay for an index patient played a primary role in MDR-TB transmission inside the school. To immediately detect TB, morning examinations in schools should be performed. TB trackers and case managers should work closely with public health workers and physicians in cases of TB outbreaks or transmissions involving students. Moreover, individuals who are in close contact with MDR-TB patients should undergo careful clinical follow-up for at least two years. Implementing a joint examination strategy to ensure early detection, diagnosis, and treatment of MDR-TB transmission is recommended.

A tuberculosis school outbreak in China, 2018: reaching an often overlooked adolescent population

Adolescents have been largely neglected from tuberculosis control efforts. In low- to medium burden settings much of the tuberculosis burden in this age group occurs from school outbreaks. We report on a large tuberculosis outbreak in adolescents from a boarding high school in Jiangsu Province, China. From March to June 2018, a tuberculosis outbreak occurred in a boarding high school. We conducted an outbreak investigation involving clinical diagnostic tests and molecular analysis to determine the outbreak origin. Cases were detected through symptom screening, tuberculin skin testing (TST), chest radiography, sputum smear, solid sputum culture and GeneXpert MTB/RIF. Mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) genotyping and spoligotyping methods were performed on Mycobacterium tuberculosis (M. tuberculosis) isolates to identify the outbreak origin. A total of 845 students and 131 teachers/staff attended a TST screening for tuberculosis infection. The prevalence of elevated tuberculin reactions at ≥5, ≥10 and ≥15 mm was 12.19% (119/976), 6.35% (62/976) and 3.28% (32/976), respectively. Radiographic abnormalities were present in 5.73% (56 of 976) individuals, 40 students and 16 teachers/staff. Of these, 12 students were diagnosed with confirmed tuberculosis. In total, 14 students (two index cases and 12 confirmed cases) were diagnosed and reported in the tuberculosis outbreak, an attack rate of 1.7% (14/847) among students (two index cases and 845 screened students). Results from MIRU-VNTR typing and spoligotyping analyses demonstrated that three M. tuberculosis strains belong to the Beijing family with corresponding MIRU-VNTR alleles. This school-based tuberculosis outbreak among adolescents demonstrates that transmission among individuals in this age group is common and must be prioritised. It suggests that identifying and timely diagnosis of smear-positive cases, especially in the early phase of outbreaks, is the key to preventing further spread among close contacts.

An outbreak of tuberculosis in a middle school in Henan, China: Epidemiology and risk factors

Background

In 2013, a tuberculosis (TB) outbreak occurred in a middle school in Henan province of China. An outbreak survey was carried out in the school.

Objectives

This study was undertaken to investigate the detection rate of TB cases and those with strong Mantoux positive (SMP), defined as tuberculin skin test (TST) indurations of 15mm or larger and/or blisters, necrosis or lymphangitis, and to identify their risk factors.

Methods

The TST, chest x-ray/radiography, and TB-suspicious symptoms interview were used to screen for TB cases. Their diagnosis was made by sputum smear microscopy, liquid culture, computed tomography (CT), and diagnostic therapy if necessary. We retrospectively analyzed the outbreak survey data of 4082 students and 278 staff in the school. Logistic regression models were used to identify the risk factors associated with SMP and TB disease.

Results

Approximately 3.55% of students and 16.55% of staff were SMP. SMP rate in students was significantly lower than that in staff (p<0.001). 55 TB cases in students and none in staff were identified in the school from February to November, 2013, with a detection rate of 1.35% for students. SMP and TB case detection rates were 20.29% and 41.77%, respectively, in the index class, both significantly higher than that in the other classes (3.26% and 0.55%, respectively; both p<0.001). In the index class, TB case detection rate over the study period in students with SMP was not significantly higher than that with TST indurations of <15mm (38.18% vs 21.43%, p = 0.24), but it was significantly higher in the other classes (7.81% vs 0.18%, p<0.001). Risk factors independently associated with SMP and TB cases shared the following with the index case: same dormitory-floor (adjusted odds ratio (AOR) 5.36, 95% CI 3.02–9.48, p<0.001 for SMP; AOR 2.67; 95% CI 1.03–6.96, p = 0.044 for TB cases), same classroom (AOR 4.01; 95% CI 1.95–8.26, p<0.001 for SMP; AOR 165.08; 95% CI 66.88–407.47, p<0.001 for TB cases), same teaching-floor in different classroom (AOR 5.41; 95% CI 3.02–9.71, p<0.001 for SMP; AOR 11.24; 95% CI 3.71–34.03, p<0.001 for TB cases) and same teaching-building on different floor (AOR 1.81; 95% CI 1.16–2.85, p = 0.009 for SMP; AOR 3.30; 95% CI 1.16–9.42, p = 0.025 for TB cases). The closer the contact was with the index case, the larger the AORs for SMP and TB cases were.

Conclusion

Same dormitory-floor, same classroom, same teaching-floor and same teaching-building with the index case were all risk factors for both TB infection and disease for students in the outbreak, and the closer the contact was with the index case, the higher the risk was observed. Attention should also be paid to students with TST indurations <15mm, as well as to those with that ≥15mm for the index class in dealing with the outbreak.

Tuberculosis outbreaks among students in mainland China: a systematic review and meta-analysis

BACKGROUND

In recent years, tuberculosis outbreaks in schools have occurred more frequently in China than in other parts of the world, and have posed a public health threat to students and their families. This systematic review aimed to understand the epidemiological characteristics of tuberculosis (TB) outbreaks and analyze the factors associated with TB outbreaks in schools in China.

METHODS

We conducted this systematic review following the standard procedures of the Cochrane Collaboration and the Preferred Reporting Items for Systematic Review and Meta-Analysis statement. The meta-analysis was performed with STATA using a random effects model.

RESULTS

We included 107 studies involving 1795 student patients with TB in mainland China. The results of the systematic analysis indicated that TB outbreaks were more frequently reported in senior middle schools and in Eastern China. The outbreaks mainly occurred during the winter and spring, and the median outbreak duration was 4 months. The meta-analysis showed that the total attack rate and the class attack rate of tuberculosis outbreaks among students were 4.60% (95% CI 3.80 to 5.70%) and 22.70% (95% CI 19.20 to 27.00%), respectively. Subgroup analysis showed that outbreaks that occurred at universities or colleges had a relatively higher attack rate than those occurred in senior middle schools. The prevalence of latent tuberculosis infection (LTBI) among close contacts was 23.70% (95% CI 19.50 to 28.90%). The median case-finding interval was 2 months, and 47.40% of the index cases had a case-finding delay.

CONCLUSION

The results of our review indicated that school TB outbreaks were reported most frequently in senior middle schools in China. The attack rates of outbreaks at universities or colleges were higher than those in senior middle schools. The TB outbreaks in schools usually occurred over prolonged periods. The case-finding delay in the index cases must be reduced to prevent transmission in classes and schools. Effective surveillance and screening of presumptive TB cases in schools should be strengthened to reduce outbreaks in schools.

Spatiotemporal Distribution of Tuberculosis during Urbanization in the New Urban Area of Nanchang City, China, 2010-2018

Background: Urbanization will play a key role in ending the tuberculosis (TB) epidemic by 2030, but understanding the relationship between urbanization and the health threats posed by TB is incomplete. Therefore, this study aimed to explore the spatiotemporal distribution of TB at the township level during urbanization in the new urban area of Nanchang. Methods: Seasonal-trend decomposition of time series analysis was used to explore the seasonal distribution and trend analysis. Global and local spatial autocorrelation statistics, and space–time scan statistics were performed to detect the spatiotemporal clusters of TB cases in the new urban area of Nanchang from 2010 to 2018. Results: A total of 3245 TB cases were reported in the study area from 2010 to 2018. Of all the TB cases, 68% occurred in individuals older than 40 years old, 73.2% were male cases, and 56.6% were farmers. The primary seasonal peak was in late spring (April), and a smaller peak was in early autumn (September). The results of local indicators of spatial association showed that Jiaoqiao town and Changleng town might be “High–High” clusters. The most likely spatiotemporal cluster was located in the southwest of the study area in 2010, which included five towns, and then shifted to the northeast gradually. Across 2010 to 2018, nine spatiotemporal clusters were identified. The most likely cluster was located at the northeast of the study area. The center of this area was in Nanji town with a circle radius of 43.74 kilometers. Conclusions: The spatial clusters of TB incidence shifted to the rural region and the fringe of the new urban area of Nanchang. Targeted management strategies for urban migrants in the process of urbanization should be strengthened.

Public Awareness of Tuberculosis in Southeast China: A Population-Based Study

Few provinces in China have recently conducted population-based surveys on tuberculosis (TB) awareness at the provincial level. Hence, we conducted a population-based, cross-sectional study to evaluate the level of awareness of TB knowledge among residents of Zhejiang Province, China from October 2018 to December 2018. A total of 7174 individuals were randomly selected to participate in this survey. The rate of awareness of key information on TB was found to be 48.0%. The study’s participants exhibited a good understanding of the transmission route (80.8%), curable outcome (78.3%), and designated treatment sites (67.0%) of TB. The rate of awareness of suspicious TB symptoms (36.1%) and the relief policy on diagnosis and first-line therapeutic drugs (38.0%) were found to be relatively low among the respondents. People living in rural areas, those who were less educated, and students all showed a low level of awareness of key knowledge about TB. In conclusion, residents in Zhejiang Province generally lacked key information about TB, which is not conducive to the early detection and treatment of TB. Corresponding efforts should be made for different groups of people to achieve favorable effects on the prevention and control of TB.

Adolescent tuberculosis associated with tuberculosis exposure in classrooms and dorm rooms in Guangxi, China

OBJECTIVE

Quantify tuberculosis (TB) risk attributable to dorm room exposure in addition to classroom exposure.

METHODS

Adolescent school contact investigations were conducted for every reported index TB case, and similar contact investigations were conducted in selected community-control classes from November 2016 to October 2017 in Guangxi, China.

RESULTS

A total of 6263 contacts of 112 index TB cases and 6130 classmates of 112 controls were investigated. There were 14, 12, and 2 new active TB cases detected among classmates/non-roommates of index cases, classmates/roommates of index cases, and control classmates, respectively. Compared with control contacts, the adjusted relative risk (95% confidence interval (CI)) and population attributable fraction (PAF) for being a classmate/non-roommate of the index case increased the risk of active TB diagnosis to 8.44 (95% CI: 1.31-54.48) and 44.1%. The adjusted RR and PAF for being a classmate/roommate of the index case was 29.37 (95% CI: 3.80, 227.11) and 41.4%. Being classmates/roommates significantly increased the risk of TB compared to a classmate/non-roommate of the index case (RR=3.48, 95% CI: 1.64, 7.40).

CONCLUSION

The additional risk of TB due to exposure in the dorm room should be taken into account in planning of TB prevention and control in boarding schools.

Diagnostic delay as main contributing factor to a large outbreak of tuberculosis in a university

OBJECTIVE

To describe the epidemiological characteristics of a large tuberculosis outbreak in the university environment and the main risk factors associated with it.

METHOD

A descriptive analysis of the data collected from sick individuals and their contacts was made. For the contact tracing, the guidelines established in the Tuberculosis Programme of the Autonomous Community of the Basque Country were followed. Six of the outbreak strains were sent to the National Centre of Microbiology for molecular typing.

RESULTS

The total number of cases of the outbreak was 11. The rate of tuberculosis infection in the classroom of the index case, including the sick individuals, was 88.1% (59 infected and only 8 uninfected). The diagnostic delay of the index case was 260 days, and in the other 8 symptomatic cases it ranged between 10 and 70 days. The pattern obtained by the 2genotyping techniques was identical in the 6 strains studied.

CONCLUSIONS

The long diagnostic delay of the authentic index case, which was diagnosed in the contact tracing, and the poor ventilation conditions of the classroom, determined the high number of secondary cases associated with this outbreak.

Tuberculosis Transmission in Households and Classrooms of Adolescent Cases Compared to the Community in China

The aim of this paper is to evaluate the link between the history of exposure to tuberculosis (TB) in the household and diagnosed TB cases at school, and to compare the detection rate of active TB among household contacts and classroom contacts of adolescent TB cases with the rates among contacts of healthy controls. From November 2016 to December 2017, a prospective matched case-control study was conducted using passively identified index adolescent student cases from the TB surveillance system and healthy controls (matched by county, school type, sex, age and ethnicity). Contacts in households and classrooms of index cases and of controls were investigated. Matched tabulation of 117 case-control pairs revealed exposure to TB in the household as a strong risk factor (odds ratio (OR) = 21.0, 95% confidence interval (CI): 3.4, 868.6). Forty-five (case detection rate 0.69%) and two (case detection rate 0.03%) new active TB cases were detected among 6512 and 6480 classroom contacts of the index cases and controls, respectively. Having an index case in the classroom significantly increased the risk of classmates contracting active TB (OR = 22.5, 95% CI: 5.9, 191.4). Our findings suggested that previous exposure to TB in the household could lead a child to catch TB at school, then spread TB to classmates.

Spatial and temporal clustering analysis of tuberculosis in the mainland of China at the prefecture level, 2005-2015

Background

Tuberculosis (TB) is still one of the most serious infectious diseases in the mainland of China. So it was urgent for the formulation of more effective measures to prevent and control it.

Methods

The data of reported TB cases in 340 prefectures from the mainland of China were extracted from the China Information System for Disease Control and Prevention (CISDCP) during January 2005 to December 2015. The Kulldorff’s retrospective space-time scan statistics was used to identify the temporal, spatial and spatio-temporal clusters of reported TB in the mainland of China by using the discrete Poisson probability model. Spatio-temporal clusters of sputum smear-positive (SS+) reported TB and sputum smear-negative (SS-) reported TB were also detected at the prefecture level.

Results

A total of 10 200 528 reported TB cases were collected from 2005 to 2015 in 340 prefectures, including 5 283 983 SS- TB cases and 4 631 734 SS + TB cases with specific sputum smear results, 284 811 cases without sputum smear test. Significantly TB clustering patterns in spatial, temporal and spatio-temporal were observed in this research. Results of the Kulldorff’s scan found twelve significant space-time clusters of reported TB. The most likely spatio-temporal cluster (RR = 3.27, P <  0.001) was mainly located in Xinjiang Uygur Autonomous Region of western China, covering five prefectures and clustering in the time frame from September 2012 to November 2015. The spatio-temporal clustering results of SS+ TB and SS- TB also showed the most likely clusters distributed in the western China. However, the clustering time of SS+ TB was concentrated before 2010 while SS- TB was mainly concentrated after 2010.

Conclusions

This study identified the time and region of TB, SS+ TB and SS- TB clustered easily in 340 prefectures in the mainland of China, which is helpful in prioritizing resource assignment in high-risk periods and high-risk areas, and to formulate powerful strategy to prevention and control TB.

Electronic supplementary material

The online version of this article (10.1186/s40249-018-0490-8) contains supplementary material, which is available to authorized users.

Recent transmission of Mycobacterium tuberculosis in China: the implication of molecular epidemiology for tuberculosis control

Tuberculosis (TB) has remained an ongoing concern in China. The national scale-up of the Directly Observed Treatment, Short Course (DOTS) program has accelerated the fight against TB in China. Nevertheless, many challenges still remain, including the spread of drug-resistant strains, high disease burden in rural areas, and enormous rural-to-urban migrations. Whether incident active TB represents recent transmission or endogenous reactivation has helped to prioritize the strategies for TB control. Evidence from molecular epidemiology studies has delineated the recent transmission of Mycobacterium tuberculosis (M. tuberculosis) strains in many settings. However, the transmission patterns of TB in most areas of China are still not clear. Studies carried out to date could not capture the real burden of recent transmission of the disease in China because of the retrospective study design, incomplete sampling, and use of low-resolution genotyping methods. We reviewed the implementations of molecular epidemiology of TB in China, the estimated disease burden due to recent transmission of M. tuberculosis strains, the primary transmission of drug-resistant TB, and the evaluation of a feasible genotyping method of M. tuberculosis strains in circulation.

Development and validation of college students' tuberculosis knowledge, attitudes and practices questionnaire (CS-TBKAPQ)

BACKGROUND

China faces many challenges in controlling tuberculosis (TB). One significant challenge is the control of college students' TB. In particular, cross-sectional studies of college students' knowledge, attitudes and practices (KAP) in regard to TB have attracted substantial attention. However, few measurement tools have been developed to aid processes related to expert consultation, pre-testing, reliability and validity testing. Our study developed the College Students' TB Knowledge Attitudes and Practices Questionnaire (CS-TBKAPQ) following the scale development steps.

METHODS

The construction of the CS-TBKAPQ was based on the Theory of Knowledge, Attitude, Belief, and Practice (KABP or KAP). The item pool was compiled from literature reviews and individual interviews. The reliability validation was assessed by calculating Cronbach's α coefficient, the split-half reliability coefficient, and the test-retest reliability coefficient. Construct validity was assessed using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). The diagnostic accuracy was evaluated using the World Health Organization Advocacy, Communication and Social Mobilization KAP Survey Questionnaire (WHO-TBKAPQ) as the reference standard.

RESULTS

A total of 31 questionnaire items were proposed. Cronbach's α coefficient, the split-half reliability coefficient and the test-retest reliability coefficient were 0.86, 0.78 and 0.91. Four factors that explained 62.52% of the total variance were also identified in EFA and confirmed in CFA. The CFA model fit indices were x ² /df = 1.82 (p < 0.001), GFI = 0.925, AGFI = 0.900, RMR = 0.068, and RMSEA = 0.049. The CS-TBKAPQ was significantly correlated with the WHO-TBKAPQ and the Chinese Public TB KAP Questionnaire (CDC-TBKAPQ) developed by the Chinese Center for Disease Control and Prevention (r = 0.59, 0.60, p < 0.001). The receiver operating characteristics curve (ROC) analysis suggested a cut-off point of 47.5, with which the CS-TBKAPQ showed a sensitivity of 73.63% and a specificity of 80.51% in identifying students with low-level KAP. The positive and negative predictive values were 83.23% and 69.91%.

CONCLUSIONS

The findings of this study demonstrate that the CS-TBKAPQ is a reliable and valid tool for measuring the KAP towards TB in college students.

Tuberculosis among Jimma University Undergraduate Students: First Insight about the Burden of Tuberculosis in Ethiopia Universities-Cross-Sectional Study

Background

Ethiopian universities are facilities where students live in relative overcrowding condition. This might favor the chance of tuberculosis transmission among students. This study was done to determine the magnitude and associated factors of tuberculosis among Jimma University students.

Methods

A cross-sectional study was done from February 2015 to July 2015. Hundred twenty-nine consented participants were interviewed using structured questionnaire. Biological specimens were collected and cultured on Mycobacterium Growth Indicator Tube. Mycobacterium tuberculosis complex verification was done by SD BIOLINE TB Ag MPT64 Rapid test. Frequency distribution, logistic regression, and independent sample t-test were used to analyze the data using SPSS Version 20.

Result

Magnitude of all forms of tuberculosis among Jimma University undergraduate students was 209.1 per 100000-student population. Contact history [AOR: 4.76, 95% CI (1.31–17.31)], smoking [AOR: 6.67, 95% CI (1.51–29.44)], khat chewing [AOR: 5.56, 95% CI (1.66–18.69)], and low body mass index [AOR: 5.37, 95% CI (1.46–19.78)] were determinants of tuberculosis.

Conclusion

The magnitude of tuberculosis among Jimma University undergraduate students is high. TB is associated with previous tuberculosis patient contact and behavioral factors. Hence, students with these risk factors should be given enough attention for the control of TB in Jimma University.

ESMPE: A combined strategy for school tuberculosis prevention and control proposed by Dalian, China

BACKGROUND

Although China has paid more attention on the prevention and control of tuberculosis (TB) in schools, several unsolved questions in this field still threaten the progress of TB control. Therefore, there is an urgent need to develop a systematic and practical strategy for Chinese school TB prevention and control system. In this study, we aimed to assess the feasibility of a combined strategy named ESMPE (examination, screening, monitoring, prevention and education) that adhere to the basic principles of Chinese schools TB control strategy.

METHODS

The ESMPE strategy included five sections, namely TB screening during physical examination for the school freshmen entrances, screening of close contacts, monitoring of high-risk schools, preventive treatment and TB education. The effectiveness of ESMPE strategy was evaluated from 2011 to 2016. The original data were provided by the Dalian Tuberculosis Hospital. Descriptive analysis and nonparametric tests were used for comparing statistical differences of results between different years.

RESULTS

The detection rate of active pulmonary TB in school freshmen was decreased from 2011 to 2016 (χ2 = 41.941, P = 6.0551E-8). 97.22% (17,043/17,530) of close contacts experienced close contacts screening, and the secondary attack rate (SAR) of TB in schools fell by 146.35/105 from 2011 to 2012, and finally reduced to 85.57/105 in 2016. There was a significant correlation between SAR of student TB and the rate of screened close contacts (r = -0.924, P = 0.009). TB incidence of five monitored schools had a substantial decline after receiving monitoring, and this declining trend continued in 2016. Due to the TB education and advanced screening methods, the mean of diagnostic delay time in students with TB was shortened (15.71 days), while still fewer latent TB infection students received preventive treatment (30.38%).

CONCLUSIONS

The ESMPE strategy has shown a favorable effect on TB prevention and control in Dalian schools. More systematic evidence is needed on the effect of this strategy in reducing the incidence of TB in schools from other settings prior to its further scaling-up in China.

The experiences of high school students with pulmonary tuberculosis in China: a qualitative study

Background

Clustered tuberculosis (TB) still occurred nationally in Chinese schools every year, where high school students patients accounts for the highest proportion. These young TB patients are in a critical period of physical and psychological growth. Research on their illness experience and analysis of underlying causes remains blank. The purpose of this study is to explore the overall illness experience of Chinese high school TB patients and to investigate the individual and social causes of such experience.

Methods

Twenty-two high school TB patients in a certain county of Shaanxi province were interviewed in-depth twice when initial diagnosed and during intermediate treatment periods. Interview data were analyzed by framework approach.

Results

The high school TB patients worried about interruption of studies rather than the disease. They generally showed a lack of awareness of tuberculosis, were highly dependent on parents, and received assistance from teachers and students during the treatment. Most of them did not show obvious stigma.

Conclusion

The unique education system and sociocultural factors in China are the root of special illness experience of high school TB patients. Huge pressure in college entrance examination leads sick students to worry about interruption of studies more than the disease itself. Their serious lack of awareness of TB, caused by the ignorance of school, parents and the students, becomes the biggest obstacle to timely diagnosis and treatment. Whether high dependence on parents is conducive to disease recovery varies with each individual. Meanwhile, patients’ weak stigma could play a positive role in disease recovery. Educational and medical institutions should develop more effective TB control strategies based on these factors.

Concurrent Outbreaks of Tuberculosis in a School and the Wider Community in Macau

Between 2009 and 2012, 22 adolescents of age 15-20 from a day school in Macau were diagnosed with tuberculosis. Detection of multiple molecular clusters may suggest the presence of concurrent outbreaks, and could reflect also ongoing transmissions in the community. Careful interpretation of molecular epidemiology data is crucial in contact investigations.

Shared air: a renewed focus on ventilation for the prevention of tuberculosis transmission

Background

Despite an improvement in the overall TB cure rate from 40–74% between 1995 and 2011, TB incidence in South Africa continues to increase. The epidemic is notably disquieting in schools because the vulnerable population is compelled to be present. Older learners (age 15–19) are at particular risk given a smear-positive rate of 427 per 100,000 per year and the significant amount of time they spend indoors. High schools are therefore important locations for potential TB infection and thus prevention efforts.

Methods and Findings

Using portable carbon dioxide monitors, we measured CO₂ in classrooms under non-steady state conditions. The threshold for tuberculosis transmission was estimated using a carbon dioxide-based risk equation. We determined a critical rebreathed fraction of carbon dioxide () of 1·6%, which correlates with an indoor CO₂ concentration of 1000 ppm. These values correspond with a ventilation rate of 8·6 l/s per person or 12 air exchanges per hour (ACH) for standard classrooms of 180 m³.

Conclusions

Given the high smear positive rate of high-school adolescents in South Africa, the proposal to achieve CO₂ levels of 1000ppm through natural ventilation (in the amount 12 ACH) will not only help achieve WHO guidelines for providing children with healthy indoor environments, it will also provide a low-cost intervention for helping control the TB epidemic in areas of high prevalence.

Seasonal variations in notification of active tuberculosis cases in China, 2005-2012

Background

Although seasonal variation in tuberculosis (TB) incidence has been described in many countries, it remains unknown in China.

Methods

A time series decomposition analysis (X-12-ARIMA) was performed to examine the seasonal variation in active TB cases nationwide from 2005 through 2012 in China. Seasonal amplitude was calculated for the evaluation of TB seasonal variation.

Results

A total of 7.78 million active TB cases were reported over a period of 8 years. A spring peak (April) was observed with seasonal amplitude of 46.3%, compared with the winter trough (February). Most cases in provinces with subtropical and tropical monsoon climate showed lower amplitudes than those in temperate continental, plateau and mountain climate regions. The magnitude of seasonality varied inversely with annual average temperature, r (95% CI) = -0.71 (-0.79, -0.61). The seasonal amplitudes were 56.7, 60.5, 40.6, 46.4 and 50.9% for patients aged ≤14, 15–24, 25–44, 45–64, and ≥65 years, respectively. Students demonstrated greater seasonal amplitude than peasants, migrant workers and workers (115.3% vs. 43.5, 41.6 and 48.1%). Patients with pulmonary TB had lower amplitude compared to patients with pleural and other extra-pulmonary TB (EPTB) (45.9% vs. 52.0 and 56.3%). Relapse cases with sputum smear positive TB (SS+ TB) had significantly higher seasonal amplitude compared to new cases with sputum smear positive TB (52.2% vs. 41.6%).

Conclusions

TB is a seasonal disease in China. The peak and trough of TB transmission actually are in winter and in autumn respectively after factors of delay are removed. Higher amplitudes of TB seasonality are more likely to happen in temperate continental, plateau and mountain climate regions and regions with lower annual average temperature, and young person, students, patients with EPTB and relapse cases with SS+ TB are more likely to be affected by TB seasonality.