Screening For Active Tuberculosis Research Articles

Cost-effectiveness analysis of a prediction model for community-based screening of active tuberculosis.

Active case finding could effectively detect tuberculosis (TB) patients, but it can be costly. Therefore, a feasible, cost-saving, and efficient algorithm for community-based TB screening is needed. The study population was based on a previous TB prevalence survey conducted in the Zambia/South Africa Tuberculosis and HIV/AIDS Reduction trial. We developed predictive scoring models for HIV-positive and HIV-negative/unknown populations for practical purposes. We compared the cost-effectiveness of our models with that of WHO tools through average cost-effectiveness ratio (ACER) and incremental cost-effectiveness ratio. The prediction model for HIV-positive population presented higher area under the curve (AUC) = 0.652, 95% confidence interval (CI) = 0.602-0.701) than WHO-recommended four-symptom screen (AUC = 0.568, 95% CI = 0.524-0.612) among South African participants. The AUC of the model for HIV-negative/unknown population was 0.673 (95% CI = 0.648-0.697), which was higher than that of the WHO tools as well. The ACER of our model can range from 246 to 1670 USD per TB case detected in the South African communities. The scoring system for active TB case finding presented a better performance and showed cost-effectiveness, which can provide new strategies for active TB case finding with multiple options under budget considerations.

New admissions and asymptomatic TB cases seem to fuel TB epidemic in prisons, a cross sectional survey in Tanzania.

There is an increased risk for tuberculosis (TB) infection and disease progression in prison settings. TB prevalence in prisons in low- and middle-income countries have been measured to be up to 50 -times higher than in the general population. The aim of the study was to perform active TB screening and estimate the burden of TB in central prisons in Tanzania mainland. We performed TB active case finding in five central prisons, Keko, Segerea, Ukonga, Butimba and Ruanda prison in Tanzania, using the Xpert on early morning or spot sputum sample from inmates and new entries between April 2014 and July 2015. A questionnaire that asked about the symptoms and risk factors for TB was administered before a sputum sample was collected. Out of 13,868 incarcerated individuals tested, 13,763 had valid results. TB prevalence among tested was 1550 per 100,000 population (214/13,763); new admissions contributed to the majority (61.68%) of TB cases, but prevalence was higher among inmates (1.75%) compared to new admissions (1.45%). Ukonga, an urban prison which incarcerates long-term convicted inmates had the highest prevalence of 4.02%. Male gender (OR = 2.51, p<0.001), repeated incarcerations (OR = 2.85, p<0.001), history of TB treatment (OR = 1.78, p = 0.002), TB symptoms (OR = 2.78, p = 0.006) and HIV infection (OR = 2.86, p = 0.002) were associated with positive TB results. New admissions could be the driving force of the TB epidemic in the penitentiary system. However, prison environments remain a major risk factor for developing active TB disease.

Accuracy of chest x-ray screening of silica-exposed miners for tuberculosis.

The World Health Organization recommends systematic chest X-ray (CXR) screening for tuberculosis (TB) in silica-exposed workers. However, evidence on the accuracy of CXR screening in such populations is lacking. To measure the accuracy of CXR screening for active TB in silica-exposed miners, in a population with a high prevalence of silicosis, post-TB lung disease and HIV. A secondary analysis of data from a miner screening programme in Lesotho was undertaken. We measured the performance of CXR (in participants with and without cough) for 'abnormalities suggestive of TB' against Xpert MTB/RIF (Xpert). The sample size was 2572 and positive Xpert prevalence was 3%. CXR alone had high sensitivity (0.93, 95% confidence interval [CI] 0.87-0.99), but low specificity (0.41, 95% CI 0.39-0.42). Requiring cough and a positive CXR increased specificity (0.79, 95% CI 0.77-0.81), resulting in reduced sensitivity (0.41, 95% CI 0.30-0.52). There was no difference in CXR accuracy by HIV status. However, specificity was markedly reduced in the presence of silicosis (from 0.70, 95% CI 0.68-0.72, to 0.03, 95% CI 0.02-0.04) or past TB history (from 0.59, 95% CI 0.56-0.62 to 0.27, 95% CI 0.25-0.29). Throughout, positive predictive value remained very low (5%) and negative predictive value very high (99%). CXR screening accurately identifies TB-negative CXRs in this population, but post-TB lung disease and silicosis would result in a high proportion of Xpert-negative referrals and an increased risk of unneeded empirical treatment. Adapted screening algorithms, practitioner training and digital access to previous mining CXRs are needed.

Prevalence and Characteristics of Tuberculosis in the Korean Homeless Population Based on Nationwide Tuberculosis Screening.

The government of Korea implemented a strategy of prevention and early diagnosis in high-risk groups to reduce the tuberculosis (TB) burden. This study aims to investigate the TB epidemiology and gap in understanding of TB prevalence among homeless individuals by analyzing active TB chest X-ray (CXR) screening results in Korea. The Korean National Tuberculosis Association conducted active TB screening with CXR for homeless groups from January 1 to December 31, 2021. Sputum acid-fast bacilli smear and culture were performed for the subjects suggestive of TB on CXR. We performed a cross-sectional analysis of the data in comparison with the national health screening results from the general population. Among 17,713 homeless persons, 40 (0.23%), 3,077 (17.37%), and 79 (0.45%) were categorized as suggested TB, inactive TB, and observation required, respectively. Prevalence of suggested TB in the homeless was significantly higher (3-5 fold) than in Univerthe national general health screening based on age category (p&lt;0.005). Twenty-nine cases were confirmed as TB, yielding a prevalence of 164 cases per 100,000 individuals; 19 of these 29 cases showed inactive TB on CXR. Body mass index (p=0.0478) and CXR result (p&lt;0.001) significantly correlated with confirmed TB based on multivariable analysis. Nutrition status and CXR results, especially that of inactive TB, should be considered in active TB screening of the homeless population, where TB prevalence is higher than the general population.

A Quasi-experimental Study on the Effect of Pre-entry Tuberculosis Screening for Immigrants on Treatment Outcomes in South Korea: A Difference-in-Differences Analysis

ObjectiveThis study ascertains the effects of the pre-entry tuberculosis (TB) screening policy, which was implemented as a strategy for managing TB among immigrants, on the treatment outcomes of immigrants in South Korea.MethodsThis study linked three different datasets from 2013 to 2018, namely (1) Korean National Tuberculosis Surveillance System; (2) National Health Information Database for patients diagnosed with TB with ICD code A15-A19, B90, or U84.3; and (3) Statistics Korea database related to cause of deaths. To identify the effect of the policy, cohorts comprising Korean and immigrant TB patients notified before (January 1, 2013–December 31, 2015) and after (September 1, 2016–December 31, 2018), the implementations of the policy were established. A difference-in-differences (DID) analysis of the treatment success and mortality rates was performed.ResultsData from 100,262 TB patients were included in the analysis (before policy implementation: 1240 immigrants and 65,723 Koreans; after policy implementation: 256 immigrants and 33,043 Koreans). The propensity score matching-DID analysis results showed that the difference in the treatment success rate between immigrants and Koreans decreased significantly, from 16% before to 6% after the policy implementation. The difference in the mortality rate between the two groups decreased from − 3% before to − 1% after the policy implementation; however, this difference was insignificant.ConclusionThe treatment outcomes of immigrant TB patients in South Korea improved after the implementation of the pre-entry active TB screening policy. Future immigrant TB policies should consider establishing active patient support strategies and a healthcare collaboration system between countries.

Uptake and Completion of Tuberculosis Preventive Treatment Using 12-Dose, Weekly Isoniazid-Rifapentine Regimen in Bangladesh: A Community-Based Implementation Study.

The United Nations high-level meeting (UNHLM) pledged to enroll 30 million in tuberculosis preventive treatment (TPT) by 2022, necessitating TPT expansion to all at tuberculosis (TB) risk. We assessed the uptake and completion of a 12-dose, weekly isoniazid-rifapentine (3HP) TPT regimen. Between February 2018 and March 2019 in Dhaka, community-based TPT using 3HP targeted household contacts of 883 confirmed drug-sensitive pulmonary TB patients. Adhering to World Health Organization guidelines, contacts underwent active TB screening before TPT initiation. Of 3193 contacts who were advised health facility visits for screening, 67% (n = 2149) complied. Among these, 1804 (84%) received chest X-rays. Active TB was diagnosed in 39 (2%) contacts; they commenced TB treatment. Over 97% of 1216 contacts began TPT, with completion rates higher among females, those with more education and income, non-slum residents, and those without 3HP-related adverse events. Adverse events, mainly mild, occurred in 5% of participants. The 3HP regimen, with its short duration, self-administered option, and minimal side effects, achieved satisfactory completion rates. A community-focused TPT approach is feasible, scalable nationally, and aligns with UNHLM targets.

Active screening for tuberculosis among high-risk populations in high-burden areas in Zhejiang province, China

ObjectivesTuberculosis (TB) is a major global public health concern. Although the incidence of TB in China is declining, the country continues to face many challenges regarding TB control. This study aimed to develop an active case finding (ACF) strategy for high-risk populations in areas with high TB burden and evaluate the effectiveness of the ACF strategy for early TB detection in patients to reduce TB transmission. Study designThis was a descriptive study. MethodsFrom May to October 2019, active TB screening was conducted in Zhejiang Province, China. Overall, 24 high-burden townships were chosen as study sites. Residents aged ≥65 years, suffering from diabetes, diagnosed with HIV/AIDS, or with a history of TB were mobilized for screening. Chest radiography was performed for all participants in the community. Sputum specimens were collected for sputum smear tests and cultures at county-level TB-designed hospitals. A professional medical team performed the final diagnoses. ResultsOverall, 130,643 residents were included, accounting for 8.85% of the total population in the selected areas. After screening, 89 confirmed cases and 419 suspected cases were identified. The detection rates for suspected and confirmed cases were 320.72/100,000 and 68.12/100,000, respectively. Individuals with a history of TB accounted for a large proportion of detected cases, and the detection rate was higher among males than in females. This study identified 10.5% of reported cases in the selected areas in 2019. In Zhejiang province, compared with the previous year, the rates of TB notification in 2019 and 2020 declined by 7.0% and 7.4%, respectively, compared with the previous year. However, the TB notification rate in 2019 was almost the same as that in 2018 (a decline of 2.5%) but sharply declined in 2020 (14.4%) in the screened areas. ConclusionsOur findings suggest that the ACF strategy may have helped to maintain the downward trends in TB notification rates by detecting patients with TB and suspected cases in the short term.

Active Tuberculosis Screening via a Mobile Health App in Myanmar: Incremental Cost-Effectiveness Evaluation.

A mobile app that calculates a tuberculosis (TB) risk score based on individual social and pathological characteristics has been shown to be a better predictor of the risk of contracting TB than conventionally used TB signs and symptoms (TBSS) in Myanmar, where the TB burden is high. Its cost-effectiveness, however, has not yet been assessed. This study aimed to determine the incremental costs of this mobile app and of chest x-rays (CXRs) in averting disability-adjusted life years (DALYs) among missed cases of active TB in the population being screened. Elements of incremental costs and effectiveness of 3 initial TB screening strategies were examined, including TBSS followed by CXR, the mobile app followed by CXR, and universal CXR. The incremental cost-effectiveness ratio (ICER; ie, the additional cost for each additional DALY averted) was compared to TBSS screening. Based on the latest 2020 gross domestic product (GDP) per capita of Myanmar (US $1477.50), the ICER was compared to willingness-to-pay (WTP) thresholds of 1, 2, and 3 times the GDP per capita. Probabilistic sensitivity analysis was conducted with a Monte Carlo simulation to compute the levels of probability that the ICER for each strategy was below each WTP threshold. For each 100,000 population, the incremental cost compared to TBSS of active TB screening was US $345,942 for the mobile app and US $1,810,712 for universal CXR. The incremental effectiveness was 325 DALYs averted for the mobile app and 576 DALYs averted for universal CXR. For the mobile app, the estimated ICER was US $1064 (72% of GDP per capita) per 1 DALY averted. Furthermore, 100% of the simulated values were below an additional cost of 1 times the GDP per capita for 1 additional DALY averted. The universal CXR strategy has an estimated ICER of US $3143 (2.1 times the GDP per capita) per 1 DALY averted and an additional 77.2% DALYs averted compared to the app (ie, 576 - 325 / 325 DALYs); however, 0.5% of the simulated values were higher than an additional expenditure of 3 times the GDP per capita. Based on the status of the economy in 2020, the mobile app strategy is affordable for Myanmar. The universal CXR strategy, although it could prevent an additional 77% of DALYs, is probably unaffordable. Compared to the TBSS strategy, the mobile app system based on social and pathological characteristics of TB has potential as a TB screening tool to identify missing TB cases and to reduce TB morbidity and mortality, thereby helping to achieve the global goal of "End TB" in resource-limited settings with a high TB burden.

Community-supported self-administered tuberculosis treatment combined with active tuberculosis screening: a pilot experience in Conakry, Guinea

ABSTRACT Directly observed treatment (DOT) for tuberculosis (TB) is recommended by the World Health Organization. However, DOT does not always meet patients’ preferences, burdens health facilities, and is hard to implement in settings where access to healthcare services is regularly interrupted. A model addressing these limitations of DOT is community-supported self-administered treatment (CS-SAT), in which patients who self-administer TB treatment receive regular visits from community members. Guinea is a country with a high TB burden, recurrent epidemics, and periodic socio-political unrest. We piloted a CS-SAT model for drug-susceptible TB patients in Conakry, led by community volunteers, who also conducted active TB case finding among household contacts and referrals for isoniazid preventive treatment (IPT) in children below 5 years old. We aimed to assess TB treatment outcomes of patients on CS-SAT and describe the number of patients identified with TB case finding and IPT provision. Prospectively enrolled bacteriologically confirmed TB patients, presenting to two facilities, received monthly TB medication. Community volunteers performed bi-weekly (initiation phase) and later monthly (continuation phase) home visits to verify treatment adherence, screen household contacts for TB, and assess IPT uptake in children under five. Among 359 enrolled TB patients, 237 (66.0%) were male, and 37 (10.3%) were HIV-positive. Three hundred forty (94.7%) participants had treatment success, seven (1.9%) died, seven (1.9%) experienced treatment failure, and five (1.4%) were lost-to-follow-up. Among 1585 household contacts screened for TB, 26 (1.6%) had TB symptoms, of whom five (19.2%) were diagnosed with pulmonary TB. IPT referral was done for 376 children from 198 households. In a challenging setting, where DOT is often not feasible, CS-SAT led to successful TB treatment outcomes and created an opportunity for active TB case finding and IPT referral. We recommend the Guinean CS-SAT model for implementation in similar settings.

The incidence rate of tuberculosis and its associated factors among HIV-positive persons in Sub-Saharan Africa: a systematic review and meta-analysis

BackgroundTuberculosis, along with HIV, is the leading cause of mortality and morbidity globally. Despite the fact that several primary studies have been conducted on the incidence rate of tuberculosis in HIV-infected people in Sub-Saharan Africa, the regional-level tuberculosis incidence rate remains unknown. The objective of this study is to determine the tuberculosis incidence rate and its associated factors in HIV-infected people in Sub-Saharan Africa.MethodsA systematic review and meta-analysis were conducted by searching four databases for studies published in English between January 1, 2000, and November 25, 2022. The study was carried out using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method. To assess the quality of the studies, the Joanna Briggs Institute critical appraisal checklist was used. A random-effects model meta-analysis was used to determine the pooled incidence of tuberculosis using STATA version 15. The I2 heterogeneity test was used to assess heterogeneity. Subgroup and sensitivity analyses were performed. Funnel plots and Egger’s regression tests were used to investigate publication bias. The pooled estimate predictors of tuberculosis incidence rate with a 95% confidence interval were also determined using the hazard ratio of each factor (HR).ResultsOut of a total of 3339 studies, 43 were included in the analysis. The overall pooled incidence rate of tuberculosis in HIV-infected people was 3.49 per 100 person-years (95% CI: 2.88–4.17). In the subgroup analysis, the pooled incidence rate of tuberculosis in HIV-infected children was 3.42 per 100 person-years (95% CI: 1.78, 5.57), and it was 3.79 per 100 person-years (95% CI: 2.63, 5.15) in adults. A meta-analysis revealed that underweight (AHR = 1.79, 95% CI: 1.61–1.96), low CD4 count (AHR = 1.23, 95% CI: 1.13–1.35), male gender (AHR = 1.43, 95% CI: 1.22–1.64), advanced WHO clinical stages (AHR = 2.29, 95% CI: 1.34–3.23), anemia (AHR = 1.73, 95% CI: 1.34–2.13), bedridden or ambulatory (AHR = 1.87, 95%), lack of isoniazid preventive therapy (AHR = 3.32, 95% CI: 1.08–2.28), and lack of cotrimoxazole (AHR = 1.68, 95% CI: 1.08–2.28) were risk factors for tuberculosis incidence. HIV patients who received antiretroviral therapy had a 0.53 times higher risk of acquiring tuberculosis than HIV patients who did not receive antiretroviral therapy (AHR = 0.53; 95% CI: 0.3–0.77).ConclusionIn this systematic review and meta-analysis study, the incidence rate of tuberculosis among HIV-positive people was higher than the WHO 2022 Africa regional estimated report. To reduce the incidence of tuberculosis among HIV patients, HIV patients should take isoniazid prevention therapy (IPT), cotrimoxazole prophylaxis, and antiretroviral therapy (ART) without interruption, as well as increase the frequency and diversity of their nutritional intake. Active tuberculosis screening should be increased among HIV-infected people.

The cascade of care for pregnant women with latent tuberculosis infection in a high-income country

Background Pregnant women have an increased risk of developing active tuberculosis (TB). The Public Health Agency of Sweden recommends screening of active TB and latent tuberculosis infection (LTBI) among pregnant women from countries with high TB incidence at Maternal Health Care (MHC) clinics. In Östergötland County, Sweden, a screening program has been active since 2013. The aim of this study was to evaluate this screening program and the cascade of care for LTBI among pregnant women in Östergötland county. Methods Data were obtained from pregnant women screened for TB at MHC clinics and subsequently referred to the pulmonary medicine clinic or the clinic of infectious diseases in Östergötland County between 2013 and 2018. The Public Health Agency of Sweden’s national database for active TB was used to analyse if any women developed active TB up to two years after the screening process. Results A total of 439 women were included. Nine cases of active TB were discovered during the screening process and two developed active TB afterward. 177 women were recommended LTBI treatment and variables significantly associated with a decreased likelihood of being recommended treatment were increasing age, time in Sweden, and parity. 137 women received and 112 (82%) completed treatment. 14 women discontinued treatment due to adverse effects. Conclusion Screening of pregnant women from countries with high TB incidence at MHC clinics led to the discovery of several cases of active TB. The completion rate of LTBI treatment was high and few discontinued due to adverse effects.

Active Screening for Tuberculosis in Sub-Saharan Africa: The Case of Mosques in the District of Bamako (Mali)

Introduction: In 2016, tuberculosis (TB) was the ninth leading cause of death worldwide and the leading cause of death due to a single infectious agent (WHO Tuberculosis Report, African Region 2016). At Mali's last census, carried out in 2009, the country's resident or legal population stood at 14,528,662, with an annual growth rate of 3.6% since 2009. The District of Bamako accounts for more than half of the urban population, i.e. 55.3% (RGPH 2009, p. 19). Mali is a highly tuberculosis-endemic country, with an estimated incidence of 56 cases per 100,000 inhabitants in 2016 (Incidence of tuberculosis in the world, World Bank link). This means that the country expects to have at least 10,000 cases of tuberculosis (TB) every year. Objective: To carry out active screening for cases of tuberculosis in places of worship in a developing country in sub-Saharan Africa. Methodology: This was a prospective cross-sectional study of active screening for TB in religious settings. We carried out systematic sampling in 02 mosques in each health district of the District of Bamako, i.e. a total of 12 mosques over a period of 03 days per commune. During the campaign period, our sample size was 1,092 participants. The campaign was preceded by a social mobilisation session with the faithful of these mosques. Results: Our study included 1,092 participants with a ratio of 1.5 in favour of men, i.e. 60.16%. The age range was 15 to 65 years and over, with the elderly being the most representative. We had 18 positive cases, representing 1.64%, the majority of whom were women (55.56%, 0.8 in favour of women). Among the positive cases, young people were more represented, with an age range of 15-24 years, representing 27.77%. In addition to the positive cases, there were 1,074 chronic coughers with negative bacilloscopy (98.35%).

Tuberculosis related barriers and facilitators among immigrants in Atlantic Canada: A qualitative study.

Tuberculosis (TB) is a disease caused by the bacterium Mycobacterium tuberculosis and affects approximately one-quarter of the world's population. Immigrant populations in Canada are disproportionately affected by TB. Canada's immigration medical examinations include screening for active TB but not latent TB infection (LTBI). In LTBI, the bacterium remains dormant within the host but can reactivate and cause disease. Once active, TB can be transmitted to close contacts sharing confined spaces leading to the possibility of outbreaks in the broader community. This study aimed to 1) assess the current TB knowledge, perceived risk, and risk behaviors of immigrants in Atlantic Canada as well as 2) identify barriers and facilitators to testing and treatment of TB among this population. Three focus group discussions were conducted with a total of 14 non-Canadian born residents of New Brunswick aged 19 years and older. Data were analyzed using inductive thematic analysis. Four themes were identified from the data relating to barriers to testing and treatment of LTBI: 1) Need for education, 2) stigma, 3) fear of testing, treatment, and healthcare system, and 4) complacency. Results included reasons individuals would not receive TB testing, treatment, or seek help, as well as facilitators to testing and treatment. These findings may inform the implemention of an LTBI screening program in Atlantic Canada and more broadly across the country.

Diabetes severity is strongly associated with the risk of active tuberculosis in people with type 2 diabetes: a nationwide cohort study with a 6-year follow-up

BackgroundMany have the rising coincidence of diabetes mellitus (DM) and endemic tuberculosis (TB). We evaluated whether the severity of diabetes is associated with an increased risk of active TB infection.Methods Using a nationally representative database from the Korean National Health Insurance System, 2, 489, 718 people with type 2 DM who underwent a regular health checkup during 2009–2012 were followed up until the end of 2018. The diabetes severity score parameters included the number of oral hypoglycemic agents (≥ 3), insulin use, diabetes duration (≥ 5 years), and the presence of chronic kidney disease (CKD) or cardiovascular disease. Each of these characteristics was scored as one point, and their sum (0–5) was used as the diabetes severity score.ResultsWe identified 21, 231 cases of active TB during a median follow-up of 6.8 years. Each parameter of the diabetes severity score was associated with an increased risk of active TB (all P < 0.001). Insulin use was the most significant factor related to the risk of TB, followed by CKD. The risk of TB increased progressively with increasing diabetes severity score. After adjusting for possible confounding factors, the hazard ratio (95% confidence interval) for TB were 1.23 (1.19–1.27) in participants with one parameter, 1.39 (1.33–1.44) in those with two parameters, 1.65 (1.56–1.73) in those with three parameters, 2.05 (1.88–2.23) in those with four parameters, and 2.62 (2.10–3.27) in those with five parameters compared with participants with no parameters.ConclusionDiabetes severity was strongly associated in a dose-dependent manner with the occurrence of active TB. People with a higher diabetes severity score may be a targeted group for active TB screening.

Knowledge, Attitude, and Stigma on Tuberculosis and the Associated Factors for Attitude Among Tuberculosis Contacts in Malaysia.

Tuberculosis (TB) is an old disease and it has infected millions of people worldwide. Since it is a highly infectious disease, many people became TB contact due to prolonged exposure to a person with TB infection. This group of people is at a higher risk of getting latent and active TB infection, hence a vulnerable group for active TB screening. This study explored the factors that determined the attitude score, the level of knowledge, attitude, and stigma (KAS) regarding TB disease among TB contact. This cross-sectional study used a validated KAS questionnaire, performed among 338 TB contacts from 5 health clinics in Kedah, Malaysia. The respondents were selected via convenience sampling. Simple and multiple linear regressions were used to analyze the data. The mean KAS scores of participants are 73.5% [standard deviation (SD)=17.06], 83.0% (SD=10.33), and 67.0% (SD=16.72), respectively. Higher income (p=0.001), better knowledge score (p<0.001), and higher stigma score (p=0.003) are the significant associated factors for the attitude score. This study revealed that most of the TB contacts have good knowledge and constructive attitude toward TB prevention and screening, but their level of stigma on TB is high. The implementation of TB education and intervention programs among TB contacts are required especially among low-income groups.

Active tuberculosis screening among the displaced population fleeing Ukraine, France, February to October 2022.

Persons fleeing Ukraine since February 2022 have potentially higher risk of tuberculosis (TB) vs all European Union countries. Interest of active TB screening among this population is debated and not widely adopted. In this screening intervention by a network of TB centres in France, the number needed to screen (NNS) was 862 to find one case. This experience shows that this strategy may be relevant for TB control in situations of massive displacement, similar to that following the Russian invasion.

The Role of Post-Bronchoscopy Sputum Examination in Screening for Active Tuberculosis.

Early diagnosis is a fundamental component of global tuberculosis control. The objective of this study was to evaluate the diagnostic yield of post-bronchoscopy sputum (PBS) testing as part of a tuberculosis diagnostic work-up. All new residents in the State of Qatar undergo a tuberculosis (TB) screening program. Those with abnormal chest radiology, negative sputum acid-fast bacilli (AFB) smears, and nucleic acid amplification testing (NAAT) for M. tuberculosis, undergo an additional bronchoscopic evaluation for TB. We prospectively enrolled individuals who were going to undergo bronchoscopy to provide two PBS samples for AFB smears and mycobacterial cultures between 18 September 2018 and 12 March 2021. A total of 495 individuals, with a median age of 31 years, were included. The majority of the patients were males (329, 66.5%). The most frequent country of origin was India (131, 26.5%) followed by the Philippines (123, 24.8%). The addition of PBS to bronchoalveolar lavage (BAL) testing allowed microbiological confirmation of tuberculosis in an additional 13 patients (3.9%), resulting in improved sensitivity (from 77.9% to 81.9%), negative predictive value (from 69.2% to 73.2%), and negative likelihood ratio (from 0.22 to 0.18). Where resources are available, the incorporation of routine PBS examination as part of tuberculosis diagnostic work-up can enhance the diagnostic yield.

Active Screening for Tuberculosis Among Street Sweepers in Ahmedabad City

Background &amp; Aims: Primary aim of Active Case Finding (ACF) is to ensure that active TB is detected early to reduce the risk of adverse outcomes as well as help in reducing TB transmission. There is a paucity of literature about prevalence of Tuberculosis among street sweepers. WHO described a high risk group for TB but it doesn’t include street sweepers though we are considering them at risk of TB due to their occupational exposure. Hence, active case finding among street sweepers is done. Materials and Methods: Cross-sectional study was conducted for active case finding of TB among street sweepers of North zone Ahmedabad. Symptomatic screening of all sweepers done and sweepers having any of the symptoms was investigated further by Chest X-ray and Sputum Microscopy. Sweeper who was diagnosed positive for TB, treatment was initiated as per NTEP guidelines. Results: Total 1200 sweepers were there in the north zone. At stage 1 43.5 % dropped out. 56 (8.25%, CI: 6.15-10.35) were having Presumptive TB. 28 sweepers participated for further testing. 50% (56-28=28) dropped out at the second stage. One Confirmed TB patient was identified and put on Treatment. Conclusion: We could reach approximately 50% of the total sweepers and the reason behind the low turnout could be the unprecedented event of covid19. Huge drops out at different stages of the screening process indicates poor health seeking behaviour, fear etc so further work to be done in this direction. Emphasis on usage of personal protective gears need to be given. Keywords: Presumptive TB, tobacco, personal protective gears.

Algorithms for Screening for Active Tuberculosis among Individuals with Latent Tuberculosis Infection in a Rural Community in China.

Screening for active tuberculosis (TB) among individuals with latent tuberculosis infection (LTBI) is important for the initiation and evaluation of TB preventive treatment. The performances of different tools and their combinations had rarely been studied in community-level screening among individuals with LTBI in China. This study aimed to explore appropriate algorithms for screening for active TB among individuals with LTBI in rural China. Three sputum samples were collected from each participant for smear microscopy, culture, and an Xpert MTB/RIF assay. Chest digital radiography and TB symptoms were investigated as well. The performances of different testing algorithms were compared with that of sputum culture as the gold standard. Overall, 1,564 study participants with LTBI were investigated, with a final diagnosis of 20 TB cases by sputum culture. Compared with other tests, the Xpert MTB/RIF assay detected 80.00% (95% confidence interval [CI], 58.40% to 91.93%) of culture-positive cases, with the highest sensitivity. When tests were combined using "or," "and," or "step" algorithms, the highest sensitivity reached 90.00% (95% CI, 69.90% to 97.21%) for the combination of the Xpert MTB/RIF assay and chest radiography, but the positive predictive value (PPV) decreased to 22.22% (95% CI, 14.54% to 32.41%). The Xpert MTB/RIF assay alone showed the best agreement with sputum culture, with a kappa value of 0.840. Pathogen molecular detection alone showed good performance compared to the other algorithms, for ruling out active TB in general LTBI, but the high cost might be a challenge for scaling it up. Identifying those with a high risk for progression to TB more precisely and establishing a cost-effective screening algorithm deserve further exploration. IMPORTANCE Enhancing community-wide active case screening in target LTBI populations is important for achieving the early treatment of active TB, and ruling active TB out is a prerequisite for initiating preventive treatment. The current study evaluated the performances of multiple tests and their combinations in screening for active TB among individuals with LTBI at the community level. Compared with the classical "TB symptoms and chest radiography" algorithm, the application of Xpert MTB/RIF improved the sensitivity from 45% to 80%. When the Xpert MTB/RIF assay was combined with chest radiography, the sensitivity was further improved to 90.00%, which achieved the World Health Organization (WHO) target product profiles. However, the algorithm requires caution as the PPV decreased from 88.89% for Xpert MTB/RIF alone to 22.22% for the combination. Xpert MTB/RIF alone offered remarkable sensitivity without compromising the PPV but would have major resource implications. Thus, identifying target populations for LTBI treatment more precisely and developing cost-effective and high-throughput screening tools and algorithms deserve further efforts.

The importance for tuberculosis of mitigating economic crises

The importance for tuberculosis of mitigating economic crises