The Spectrum of Tuberculosis Disease in an Urban Ugandan Community and Its Health Facilities

BACKGROUND

New, sensitive diagnostic tests facilitate identification and investigation of milder forms of tuberculosis (TB) disease. We used community-based TB testing with the Xpert MTB/RIF Ultra assay ("Ultra") to characterize individuals with previously undiagnosed TB and compare them to those from the same community who were diagnosed with TB through routine care.

METHODS

We offered community-based sputum Ultra testing to adult residents of a well-defined area (population 34 000 adults) in Kampala, Uganda, via door-to-door screening and venue-based testing, then used detailed interview and laboratory testing to characterize TB-positive individuals. We compared these individuals to residents diagnosed with pulmonary TB at local health facilities and a representative sample of residents without TB (controls).

RESULTS

Of 12 032 residents with interpretable Ultra results, 113 (940 [95% confidence interval {CI}, 780-1130] per 100 000) tested positive, including 71 (63%) positive at the lowest (trace) level. A spectrum of TB disease was observed in terms of chronic cough (93% among health facility-diagnosed cases, 77% among residents with positive community-based Ultra results at levels above trace, 33% among trace-positive community participants, and 18% among TB-negative controls), TB symptom prevalence (99%, 87%, 60%, and 38%, respectively), and C-reactive protein (75th percentile: 101 mg/L, 28 mg/L, 6 mg/L, and 4 mg/L, respectively). Community-diagnosed cases were less likely than health facility-diagnosed cases to have human immunodeficiency virus coinfection or previous TB. The specificity of Ultra was 99.4% (95% CI, 99.2%-99.5%) relative to a single spot sputum culture.

CONCLUSIONS

People with undiagnosed prevalent TB in the community have different characteristics than those diagnosed with pulmonary TB in health facilities. Newer diagnostic tests may identify a group of people with early or very mild disease.

Empiric treatment of pulmonary TB in the Xpert era: Correspondence of sputum culture, Xpert MTB/RIF, and clinical diagnoses

Background

Clinical tuberculosis diagnosis and empiric treatment have traditionally been common among patients with negative bacteriologic test results. Increasing availability of rapid molecular diagnostic tests, including Xpert MTB/RIF and the new Xpert Ultra cartridge, may alter the role of empiric treatment.

Methods

We prospectively enrolled outpatients age > = 15 who were evaluated for pulmonary tuberculosis at three health facilities in Kampala, Uganda. Using sputum mycobacterial culture, interviews, and clinical record abstraction, we estimated the accuracy of clinical diagnosis relative to Xpert and sputum culture and assessed the contribution of clinical diagnosis to case detection.

Results

Over a period of 9 months, 99 patients were diagnosed with pulmonary tuberculosis and subsequently completed sputum culture; they were matched to 196 patients receiving negative tuberculosis evaluations in the same facilities. Xpert was included in the evaluation of 291 (99%) patients. Compared to culture, Xpert had a sensitivity of 92% (95% confidence interval 83–97%) and specificity of 95% (92–98%). Twenty patients with negative Xpert were clinically diagnosed with tuberculosis and subsequently had their culture status determined; two (10%) were culture-positive. Considering all treated patients regardless of Xpert and culture data completeness, and considering treatment initiations before a positive Xpert (N = 4) to be empiric, 26/101 (26%) tuberculosis treatment courses were started empirically. Compared to sputum smear- or Xpert-positive patients with positive cultures, empirically-treated, Xpert-negative patients with negative cultures had higher prevalence of HIV (67% versus 37%), shorter duration of cough (median 4 versus 8 weeks), and lower inflammatory markers (median CRP 7 versus 101 mg/L).

Conclusion

Judged against sputum culture in a routine care setting of high HIV prevalence, the accuracy of Xpert was high. Clinical judgment identified a small number of additional culture-positive cases, but with poor specificity. Although clinicians should continue to prescribe tuberculosis treatment for Xpert-negative patients whose clinical presentations strongly suggest pulmonary tuberculosis, they should also carefully consider alternative diagnoses.

Risk Factors for Central Nervous System Tuberculosis

OBJECTIVES

To describe the epidemiology and factors associated with pediatric central nervous system (CNS) tuberculosis (TB) in California from 1993 to 2011.

METHODS

We analyzed California TB registry data for persons aged ≤18 years, comparing CNS TB cases versus non-CNS TB cases reported from 1993 to 2011. Factors associated with CNS TB and TB deaths were identified by using multivariate logistic regression.

RESULTS

A total of 200 CNS TB cases were reported. Compared with non-CNS TB case patients, CNS TB case patients were more likely to be aged <5 years (72.0% vs 43.6%; odds ratio [OR]: 3.8 [95% confidence interval (CI): 2.4-5.9]), US-born (82.0% vs 58.2%; OR: 3.3 [CI: 2.3-4.7]), and Hispanic (75.0% vs 63.2%; OR: 1.7 [CI: 1.3-2.4]). Among US-born CNS TB case patients (during 2010-2011), 76.5% had a foreign-born parent. Tuberculin skin test results were negative in 38.2% of 170 CNS TB cases tested. In multivariate analysis, age <5 years (adjusted odds ratio [aOR]: 3.3 [CI: 2.0-5.4]), US birth (aOR: 1.8 [CI 1.2-2.7]), and Hispanic ethnicity (aOR: 1.5 [CI: 1.1-2.1]) were associated with an increased risk of developing CNS TB. For deaths, CNS TB (aOR: 3.8 [CI: 1.4-9.9]) and culture positivity (aOR: 6.2 [CI: 2.2-17.3]) were associated with increased risk of death, whereas tuberculin skin test positivity (aOR: 0.1 [CI: 0.04-0.2]) was associated with decreased risk.

CONCLUSIONS

Subsets of children are at increased risk for CNS TB in California and may benefit from additional prevention efforts.

Is distance associated with tuberculosis treatment outcomes? A retrospective cohort study in Kampala, Uganda

Background

Challenges accessing nearby health facilities may be a barrier to initiating and completing tuberculosis (TB) treatment. We aimed to evaluate whether distance from residence to health facility chosen for treatment is associated with TB treatment outcomes.

Methods

We conducted a retrospective cohort study of all patients initiating TB treatment at six health facilities in Kampala from 2014 to 2016. We investigated associations between distance to treating facility and unfavorable TB treatment outcomes (death, loss to follow up, or treatment failure) using multivariable Poisson regression.

Results

Unfavorable treatment outcomes occurred in 20% (339/1691) of TB patients. The adjusted relative risk (aRR) for unfavorable treatment outcomes (compared to treatment success) was 0.87 (95% confidence interval [CI] 0.70, 1.07) for patients living ≥2 km from the facility compared to those living closer. When we separately compared each type of unfavorable treatment outcome to favorable outcomes, those living ≥2 km from the facility had increased risk of death (aRR 1.42 [95%CI 0.99, 2.03]) but decreased risk for loss to follow-up (aRR 0.57 [95%CI 0.41, 0.78]) than those living within 2 km.

Conclusions

Distance from home residence to TB treatment facility is associated with increased risk of death but decreased risk of loss to follow up. Those who seek care further from home may have advanced disease, but once enrolled may be more likely to remain in treatment.

Evaluation of the uptake of tuberculosis preventative therapy for people living with HIV in Namibia: a multiple methods analysis

Background

In 2016, Namibia had ~ 230,000 people living with HIV (PLHIV) and 9154 new tuberculosis (TB) cases, including 3410 (38%) co-infected cases. TB preventative therapy (TPT), consisting of intensive case finding and isoniazid preventative therapy, is critical to reducing TB disease and mortality.

Methods

Between November 2014 and February 2015, data was abstracted from charts of PLHIV enrolled in HIV treatment. Fifty-five facilities were purposively selected based on patient volume, type and location. Charts were randomly sampled. The primary outcome was to estimate baseline TPT in PLHIV, using nationally weighted proportions. Qualitative surveys were conducted and summarized to evaluate TPT practices and quantify challenges encountered by health care workers (HCW).

Results

Among 861 PLHIV sampled, 96% were eligible for TPT services, of which 87.1% were screened for TB at least once. For PLHIV eligible for preventative therapy (646/810; 82.6%), 45.4% (294/646) initiated therapy and 45.7% (139/294) of those completed therapy. The proportion of eligible PLHIV completing TB screening, initiating preventative therapy and then completing preventative therapy was 20.7%. Qualitative surveys with 271 HCW identified barriers to TPT implementation including: lack of training (61.3% reported receiving training on TPT); misunderstandings about timing of TPT initiation (46.7% correctly reported TPT should be started with antiretroviral therapy); and variable screening practices and responsibilities (66.1% of HCWs screened for TB at every encounter). Though barriers were evident, 72.2% HCWs surveyed described their clinical performance as very good, often placing responsibility of difficulties on patients and downplaying challenges like staff shortages and medication stock outs.

Conclusions

In this study, only 1 in 5 eligible PLHIV completed the TPT cascade in Namibia. Lack of training, irregularities with TB screening and timing of TPT, unclear prescribing and recording responsibilities, and a clinical misperception may have contributed to suboptimal programmatic implementation. Addressing these challenges will be critical with continued TPT scale-up.

Epidemiology of tuberculosis cases with end-stage renal disease, California, 2010

BACKGROUND/AIMS

Few studies have compared population-based tuberculosis (TB) incidence rates by end-stage renal disease (ESRD) status. No studies have compared TB genotypes by ESRD status to determine whether TB disease resulted from recent transmission or reactivation of latent TB infection (LTBI). We calculated TB incidence rates and compared demographic and clinical characteristics and genotypes among TB cases by ESRD status.

METHODS

This analysis was based on prospective surveillance for TB cases during 2010 in California. Clustered genotype was defined as ≥2 culture-positive TB cases with matching genotypes in the same county. The χ(2) or Wilcoxon rank-sum test was used to compare variables.

RESULTS

During 2010, 83 TB cases with ESRD and 2,244 cases without ESRD were reported in California; TB incidence rates were 110.3/100,000 and 6.0/100,000, respectively. ESRD case patients versus patients without ESRD were more likely to be older (median age 66 vs. 49 years; p < 0.001), foreign-born persons who had arrived in the USA >5 years before TB diagnosis (97 vs. 75%; p < 0.001) and dead at TB diagnosis (7 vs. 2%; p = 0.01). ESRD patients were less likely to have a positive tuberculin skin test (50 vs. 80%; p < 0.001), positive acid-fast bacilli sputum smears (33 vs. 53%; p = 0.01) and cavities on chest radiography (6 vs. 21%; p = 0.01). No differences in proportions of clustered TB genotypes were detected (20 vs. 23%; p = 0.54).

CONCLUSIONS

Rates of TB are 18 times higher in California's ESRD population, and TB disease likely occurred due to LTBI reactivation because few patients had clustered genotypes. Efforts to prevent TB among ESRD patients may require the use of newer diagnostic tests and promotion of LTBI treatment.

Trends in Tuberculosis Cases Among Nursing Home Residents, California, 2000 to 2009

OBJECTIVES

To examine trends in tuberculosis (TB) incidence and to compare demographic and clinical characteristics of nursing home (NH) residents and community-dwelling older adults.

DESIGN

Prospective TB surveillance.

SETTING

TB cases reported in California from 2000 to 2009.

PARTICIPANTS

TB patients aged 65 and older.

MEASUREMENTS

Trends in TB incidence per 100,000 population were assessed using Poisson regression. Demographic and clinical characteristics were compared using the chi-square or Wilcoxon rank-sum test. Among NH residents, risk factors for death during TB treatment were identified using logistic regression.

RESULTS

From 2000 to 2009, TB incidence rates decreased significantly, from 15.9/100,000 to 8.4/100,000 (-44%, 95% confidence interval (CI) = -66% to -7%) for NH residents and from 21.2/100,000 to 15.0/100,000 (-27%, 95% CI = -29% to -24%) for community-dwelling older adults. Overall, 211 TB cases among NH residents and 6,518 cases among community-dwelling older adults were reported. NH residents were more likely than community-dwelling older adults to be older (median age 81 vs 75, P < .001), have a negative acid-fast bacilli sputum smear and positive culture (37% vs 28%, P < .001), and die while undergoing TB treatment (44% vs 14%, P < .001), and were less likely to have a positive tuberculin skin test (TST) (28% vs 44%, P < .001) and have TB care provided by a health department (20% vs 59%, P < .001). In multivariable analysis, NH residents who had a positive TST were less likely to die while undergoing TB treatment (odds ratio = 0.39, 95% CI = 0.16-0.96).

CONCLUSION

TB incidence rates were lower, and reductions in incidence were greater among NH residents; community-dwelling older adults had higher TB rates and smaller reductions in incidence. Interventions that promote timely detection and treatment of TB infection and disease may be needed to reduce morbidity and mortality among NH residents.

A systematic review of the number needed to screen for active TB among people living with HIV

BACKGROUND: Systematic screening for active TB is recommended for all people living with HIV (PLWH); however, case detection remains poor globally. We investigated the yield of active case finding (ACF) by calculating the number needed to screen (NNS) to detect a case of active TB among PLWH.METHODS: We identified studies reporting ACF for TB among PLWH published from November 2010 to February 2020. We calculated crude NNS for Xpert- or culture-confirmed TB and weighted mean NNS stratified by screening approach, population/risk group, and country TB burden.RESULTS: Of the 27,221 abstracts screened, we identified 58 studies eligible for inclusion, including 5 in low/moderate TB incidence settings and 53 in medium/high incidence settings. Populations screened for TB included inpatients, outpatients not receiving antiretroviral therapy (ART), outpatients receiving ART, those with CD4 < 200 cells/µL, children aged ≤15 years, pregnant PLWH, and PLWH in prisons. Screening tools included symptom-based screening, chest X-ray, C-reactive protein levels, and Xpert. The weighted mean NNS varied across groups but was consistently low, ranging from 4 among inpatients in moderate/high TB burden settings to 137 among pregnant PLWH in moderate/high TB burden settings.CONCLUSIONS: ACF is a high yield intervention among PLWH. Approaches to screening should be tailored to local epidemiological and health-system contexts, and sensitive screening tools such as Xpert should be implemented where feasible.

Number needed to screen for TB in clinical, structural or occupational risk groups

BACKGROUND: Screening for active TB using active case-finding (ACF) may reduce TB incidence, prevalence, and mortality; however, yield of ACF interventions varies substantially across populations. We systematically reviewed studies reporting on ACF to calculate the number needed to screen (NNS) for groups at high risk for TB.METHODS: We conducted a literature search for studies reporting ACF for adults published between November 2010 and February 2020. We determined active TB prevalence detected through various screening strategies and calculated crude NNS for - TB confirmed using culture or Xpert® MTB/RIF, and weighted mean NNS stratified by screening strategy, risk group, and country-level TB incidence.RESULTS: We screened 27,223 abstracts; 90 studies were included (41 in low/moderate and 49 in medium/high TB incidence settings). High-risk groups included inpatients, outpatients, people living with diabetes (PLWD), migrants, prison inmates, persons experiencing homelessness (PEH), healthcare workers, and miners. Screening strategies included symptom-based screening, chest X-ray and Xpert testing. NNS varied widely across and within incidence settings based on risk groups and screening methods. Screening tools with higher sensitivity (e.g., Xpert, CXR) were associated with lower NNS estimates.CONCLUSIONS: NNS for ACF strategies varies substantially between adult risk groups. Specific interventions should be tailored based on local epidemiology and costs.

Prevalence of self-reported HIV testing and associated factors among adolescent girls and young women in South Africa: Results from a 2017 nationally representative population-based HIV survey

Objectives

This article estimated the prevalence of self-reported HIV testing and identified associated factors among sexually active adolescent girls and young women (AGYW), aged 15–24 years, in South Africa.

Study design

This is a secondary data analysis of a nationally representative population-based cross-sectional multi-stage cluster survey of households in South Africa conducted in 2017.

Methods

Descriptive statistics were used to describe AGYW characteristics and the multivariable logistic regression model was used to determine factors associated with HIV testing. All analyses were adjusted for unequal sampling probabilities using survey weights.

Results

From the 1360 AGYW analysed (70.3% aged 20–24 years, 89.0% Black African, 95.5% unmarried, 88.7% unemployed), 1154 (estimate 85.8% (95% Confidence Interval (CI): 83.0 to 88.1)) had ever tested for HIV. In adjusted analysis, AGYW who had been pregnant in the past 24 months (adjusted Odds Ratio [aOR] 3.67, 95%CI: 1.68 to 8.02), were older (20–24 years: aOR 3.13, 95%CI: 1.86 to 5.28), or did not use condoms consistently compared to using them every time (almost every time: aOR 3.31, 95%CI: 1.07 to 10.22; sometimes: aOR 2.54, 95%CI: 1.29 to 4.98) had significantly higher odds of ever testing for HIV.

Conclusions

This research identified an unmet need for HIV testing among AGYW and increasing awareness of HIV counselling and testing among AGYW in South Africa is recommended.

•

The prevalence of self-reported HIV testing among AGYW in South Africa in 2017 was 85.8% (95% CI: 83.0 to 88.1).

•

Being pregnant in the past 24 months is associated with HIV testing among AGYW in South Africa.

•

Being older (20–24 years) is associated with HIV testing among AGYW in South Africa.

•

Inconsistent use of condoms is associated with HIV testing among AGYW in South Africa.

•

There is an unmet need for HIV testing among AGYW in South Africa.

Ending tuberculosis in a post-COVID-19 world: a person-centred, equity-oriented approach

The COVID-19 pandemic has disrupted systems of care for infectious diseases-including tuberculosis-and has exposed pervasive inequities that have long marred efforts to combat these diseases. The resulting health disparities often intersect at the individual and community levels in ways that heighten vulnerability to tuberculosis. Effective responses to tuberculosis (and other infectious diseases) must respond to these realities. Unfortunately, current tuberculosis programmes are generally not designed from the perspectives of affected individuals and fail to address structural determinants of health disparities. We describe a person-centred, equity-oriented response that would identify and focus on communities affected by disparities, tailor interventions to the mechanisms by which disparities worsen tuberculosis, and address upstream determinants of those disparities. We detail four key elements of the approach (data collection, programme design, implementation, and sustainability). We then illustrate how organisations at multiple levels might partner and adapt current practices to incorporate these elements. Such an approach could generate more substantial, sustainable, and equitable reductions in tuberculosis burden at the community level, highlighting the urgency of restructuring post-COVID-19 health systems in a more person-centred, equity-oriented way.

Characterization of geographic mobility among participants in facility- and community-based tuberculosis case finding in urban Uganda

Background

International and internal migration are recognized risk factors for tuberculosis (TB). Geographic mobility, including travel for work, education, or personal reasons, may also play a role in TB transmission, but this relationship is poorly defined. We aimed to define geographic mobility among participants in facility- and community-based TB case finding in Kampala, Uganda, and to assess associations between mobility, access to care, and TB disease.

Methods

We included consecutive individuals age ≥15 years diagnosed with TB disease through either routine health facility practices or community-based case finding (consisting of door-to-door testing, venue-based screening, and contact investigation). Each case was matched with one (for community-based enrollment) or two (health facility enrollment) TB-negative controls. We conducted a latent class analysis (LCA) of eight self-reported characteristics to identify and define mobility; we selected the best-fit model using Bayesian Information Criterion. We assessed associations between mobility and TB case status using multivariable conditional logistic regression.

Results

We enrolled 267 cases and 432 controls. Cases were more likely than controls to have been born in Kampala (p<0.001); there was no difference between cases and controls for remaining mobility characteristics. We selected a two-class LCA model; the “mobile” class was perfectly correlated with a single variable: travel (>3 km) from residence ≥2 times per month. Mobility was associated with a 28% reduction in odds of being a TB case (adjusted matched odds ratio 0.72 [95% confidence interval 0.49, 1.06]).

Conclusion

Frequency of out-of-neighborhood travel is an easily measured variable that correlates closely with predicted mobility class membership. Mobility was associated with decreased risk of TB disease; this may be in part due to the higher socioeconomic status of mobile individuals in this population. However, more research is needed to improve assessment of mobility and understand how mobility affects disease risk and transmission.

Recommendations to the Society for Epidemiologic Research for Further Promoting Diversity and Inclusion at the Annual Meeting and Beyond

Increasing diverse engagement in the Society for Epidemiologic Research (SER) will positively impact the field of epidemiology. As the largest and longest-running epidemiologic society in North America, SER has long been a pioneer in promoting diversity and inclusion. A recent survey of SER members, however, showed there is still room for improving diversity, inclusion, representation, and participation in the Society. In this commentary, as members of both the SER and the Johns Hopkins Bloomberg School of Public Health Department of Epidemiology's Inclusion, Diversity, Equity, Anti-Racism, and Science (Epi IDEAS) Working Group, we recommend 4 goals for the SER Annual Meeting and beyond: 1) convene epidemiologic researchers with diverse backgrounds and ideas; 2) promote an inclusive environment at the SER Annual Meeting; 3) develop, compile, and disseminate best practices to honor diversity in epidemiologic research; and 4) increase prioritization of health disparities research and methods. We also suggest strategies for achieving these goals so that SER can better include, support, and elevate members from historically disadvantaged groups. While our recommendations are tailored specifically to SER, the greater epidemiologic and academic communities could benefit from adopting these goals and strategies within their professional societies and conferences.

Spatial distribution of people diagnosed with tuberculosis through routine and active case finding: a community-based study in Kampala, Uganda

BACKGROUND

Routine tuberculosis (TB) notifications are geographically heterogeneous, but their utility in predicting the location of undiagnosed TB cases is unclear. We aimed to identify small-scale geographic areas with high TB notification rates based on routinely collected data and to evaluate whether these areas have a correspondingly high rate of undiagnosed prevalent TB.

METHODS

We used routinely collected data to identify geographic areas with high TB notification rates and evaluated the extent to which these areas correlated with the location of undiagnosed cases during a subsequent community-wide active case finding intervention in Kampala, Uganda. We first enrolled all adults who lived within 35 contiguous zones and were diagnosed through routine care at four local TB Diagnosis and Treatment Units. We calculated average monthly TB notification rates in each zone and defined geographic areas of "high risk" as zones that constituted the 20% of the population with highest notification rates. We compared the observed proportion of TB notifications among residents of these high-risk zones to the expected proportion, using simulated estimates based on population size and random variation alone. We then evaluated the extent to which these high-risk zones identified areas with high burdens of undiagnosed TB during a subsequent community-based active case finding campaign using a chi-square test.

RESULTS

We enrolled 45 adults diagnosed with TB through routine practices and who lived within the study area (estimated population of 49 527). Eighteen zones reported no TB cases in the 9-month period; among the remaining zones, monthly TB notification rates ranged from 3.9 to 39.4 per 100 000 population. The five zones with the highest notification rates constituted 62% (95% CI: 47-75%) of TB cases and 22% of the population-significantly higher than would be expected if population size and random chance were the only determinants of zone-to-zone variation (48%, 95% simulation interval: 40-59%). These five high-risk zones accounted for 42% (95% CI: 34-51%) of the 128 cases detected during the subsequent community-based case finding intervention, which was significantly higher than the 22% expected by chance (P < 0.001) but lower than the 62% of cases notified from those zones during the pre-intervention period (P = 0.02).

CONCLUSIONS

There is substantial heterogeneity in routine TB notification rates at the zone level. Using facility-based TB notification rates to prioritize high-yield areas for active case finding could double the yield of such case-finding interventions.

Evaluation of underweight status may improve identification of the highest-risk patients during outpatient evaluation for pulmonary tuberculosis

BACKGROUND

When evaluating symptomatic patients for tuberculosis (TB) without access to same-day diagnostic test results, clinicians often make empiric decisions about starting treatment. The number of TB symptoms and/or underweight status could help identify patients at highest risk for a positive result. We sought to evaluate the usefulness of BMI assessment and a count of characteristic TB symptoms for identifying patients at highest risk for TB.

METHODS

We enrolled adult patients receiving pulmonary TB diagnoses and a representative sample with negative TB evaluations at four outpatient health facilities in Kampala, Uganda. We asked patients about symptoms of chronic cough, night sweats, chest pain, fever, hemoptysis, or weight loss; measured height and weight; and collected sputum for mycobacterial culture. We evaluated the diagnostic accuracy (for culture-positive TB) of two simple scoring systems: (a) number of TB symptoms, and (b) number of TB symptoms plus one or more additional points for underweight status (body mass index [BMI] ≤ 18.5 kg/m2).

RESULTS

We included 121 patients with culture-positive TB and 370 patients with negative culture results (44 of whom had been recommended for TB treatment by evaluating clinicians). Of the six symptoms assessed, the median number of symptoms that patients reported was two (interquartile range [IQR]: 1, 3). The median BMI was 20.9 kg/m2 (IQR: 18.6, 24.0), and 118 (24%) patients were underweight. Counting the number of symptoms provided an area under the Receiver Operating Characteristic curve (c-statistic) of 0.77 (95% confidence interval, CI: 0.72, 0.81) for identifying culture-positive TB; adding two points for underweight status increased the c-statistic to 0.81 (95%CI: 0.76, 0.85). A cutoff of ≥3 symptoms had sensitivity and specificity of 65% and 74%, whereas a score of ≥4 on the combined score (≥2 symptoms if underweight, ≥4 symptoms if not underweight) gave higher sensitivity and specificity of 69% and 81% respectively. A sensitivity analysis defining TB by Xpert MTB/RIF status produced similar results.

CONCLUSION

A count of patients' TB symptoms may be useful in clinical decision-making about TB diagnosis. Consideration of underweight status adds additional diagnostic value.

Number Needed to Screen for Tuberculosis Disease Among Children: A Systematic Review

CONTEXT

Improving detection of pediatric tuberculosis (TB) is critical to reducing morbidity and mortality among children.

OBJECTIVE

We conducted a systematic review to estimate the number of children needed to screen (NNS) to detect a single case of active TB using different active case finding (ACF) screening approaches and across different settings.

DATA SOURCES

We searched 4 databases (PubMed, Embase, Scopus, and the Cochrane Library) for articles published from November 2010 to February 2020.

STUDY SELECTION

We included studies of TB ACF in children using symptom-based screening, clinical indicators, chest x-ray, and Xpert.

DATA EXTRACTION

We indirectly estimated the weighted mean NNS for a given modality, location, and population using the inverse of the weighted prevalence. We assessed risk of bias using a modified AXIS tool.

RESULTS

We screened 27 221 titles and abstracts, of which we included 31 studies of ACF in children < 15 years old. Symptom-based screening was the most common screening modality (weighted mean NNS: 257 [range, 5-undefined], 19 studies). The weighted mean NNS was lower in both inpatient (216 [18-241]) and outpatient (67 [5-undefined]) settings (107 [5-undefined]) compared with community (1117 [28-5146]) and school settings (464 [118-665]). Risk of bias was low.

LIMITATIONS

Heterogeneity in the screening modalities and populations make it difficult to draw conclusions.

CONCLUSIONS

We identified a potential opportunity to increase TB detection by screening children presenting in health care settings. Pediatric TB case finding interventions should incorporate evidence-based interventions and local contextual information in an effort to detect as many children with TB as possible.

The impact of time at home on potential yield of home-based TB contact investigation

BACKGROUND: The yield of TB contact tracing is often limited by challenges in reaching individuals during the screening process. We investigated the times at which index patients and household contacts were typically at home and the potential effects of expanding the timing of home-based contact investigation.METHODS: Index patients and household contacts in Kampala, Uganda, were asked about their likely availability at different day/time combinations. We calculated the "participant identification gap" (defined as the proportion of participants who reported being home <50% of the time) during business hours only. We then estimated the incremental reduction in the participant identification gap if hours were expanded to include weekday evenings, Saturdays, and Sundays. Statistical significance was assessed using McNemar´s tests.RESULTS: Nearly half of eligible individuals (42% of index patients and 52% of contacts) were not likely to be home during contact investigation conducted only during business hours. Expanding to weekday evenings, Saturdays, and Sundays would reduce this participant identification gap to 15% among index patients and 18% among contacts - while also reducing differences by sex and employment.CONCLUSIONS: Expanding hours for conducting contact investigation or other home-based health interventions could substantially reduce the number of individuals missed and address disparities in access to care.

Demographic and Geographic Characterization of Excess Mortality During the COVID-19 Pandemic in Baltimore City, Maryland, March 2020 to March 2021

Estimates of excess mortality can provide insight into direct and indirect impacts of the coronavirus disease 2019 (COVID-19) pandemic beyond deaths specifically attributed to COVID-19. We analyzed death certificate data from Baltimore City, Maryland, from March 1, 2020, to March 31, 2021, and found that 1,725 individuals (95% confidence interval: 1,495, 1,954) died in excess of what was expected from all-cause mortality trends in 2016-2019; 1,050 (61%) excess deaths were attributed to COVID-19. Observed mortality was 23%-32% higher than expected among individuals aged 50 years and older. Non-White residents of Baltimore City also experienced 2 to 3 times higher rates of excess mortality than White residents (e.g., 37.4 vs. 10.7 excess deaths per 10,000 population among Black residents vs. White residents). There was little to no observed excess mortality among residents of hospice, long-term care, and nursing home facilities, despite accounting for nearly 30% (312/1,050) of recorded COVID-19 deaths. There was significant geographic variation in excess mortality within the city, largely following racial population distributions. These results demonstrate the substantial and unequal impact of the COVID-19 pandemic on Baltimore City residents and the importance of building robust, timely surveillance systems to track disparities and inform targeted strategies to remediate the impact of future epidemics.

Decline in prevalence of tuberculosis following an intensive case finding campaign and the COVID-19 pandemic in an urban Ugandan community

BACKGROUND

Systematic screening is a potential tool for reducing the prevalence of tuberculosis (TB) and counteracting COVID-19-related disruptions in care. Repeated community-wide screening can also measure changes in the prevalence of TB over time.

METHODS

We conducted serial, cross-sectional TB case finding campaigns in one community in Kampala, Uganda, in 2019 and 2021. Both campaigns sought sputum for TB testing (Xpert MTB/RIF Ultra) from all adolescents and adults. We estimated the prevalence of TB among screening participants in each campaign and compared characteristics of people with TB across campaigns. We simultaneously enrolled and characterised community residents who were diagnosed with TB through routine care and assessed trends in facility-based diagnosis.

RESULTS

We successfully screened 12 033 community residents (35% of the estimated adult/adolescent population) in 2019 and 11 595 (33%) in 2021. In 2019, 0.94% (95% CI: 0.77% to 1.13%) of participants tested Xpert positive (including trace). This proportion fell to 0.52% (95% CI: 0.40% to 0.67%) in 2021; the prevalence ratio was 0.55 (95% CI: 0.40 to 0.75)). There was no change in the age (median 26 vs 26), sex (56% vs 59% female) or prevalence of chronic cough (49% vs 54%) among those testing positive. By contrast, the rate of routine facility-based diagnosis remained steady in the 8 months before each campaign (210 (95% CI: 155 to 279) vs 240 (95% CI: 181 to 312) per 100 000 per year).

CONCLUSIONS

Following an intensive initial case finding campaign in an urban Ugandan community in 2019, the burden of prevalent TB as measured by systematic screening had decreased by 45% in 2021, despite the intervening COVID-19 pandemic.

Higher-dose rifampin for the treatment of pulmonary tuberculosis: a systematic review

OBJECTIVE

To provide a descriptive synthesis of the evidence assessing the efficacy and safety of higher doses of rifampin (RMP) for the treatment of pulmonary tuberculosis (TB).

METHODS

Systematic review of randomized controlled trials that evaluate a range of RMP doses, including doses higher than standard (>10 mg/kg or >600 mg), used as part of combination drug therapies for pulmonary TB. Two reviewers applied inclusion criteria, assessed trial quality and extracted data. Inclusion criteria were smear- or culture-confirmed pulmonary TB, and English and French language articles. Exclusion criteria were RMP monotherapy and smear-negative TB. Outcomes included were sputum culture conversion, treatment failure, recurrence and adverse events, including hepatotoxicity and flu-like syndrome.

RESULTS

Of 14 trials (4256 participants) identified, 12 were conducted before 1980. Four trials were considered high quality according to published guidelines. Study characteristics, including history of prior TB treatment, dose of RMP, duration of treatment, timing of introduction of intervention treatment, concomitant drugs, and duration of follow-up, varied, making synthesis of efficacy data challenging. Several trials suggested an advantage in terms of likelihood of culture conversion among patients receiving at least 900 mg RMP. However, an increased incidence of flu-like syndrome was seen when RMP doses of 900 mg and higher were given intermittently.

CONCLUSION

Historical trials suggest that higher than standard RMP dosing results in improved culture conversion rates. Phase 2 and 3 clinical trials evaluating higher doses of RMP and other rifamycins are needed to confirm efficacy and assure tolerability. Pharmacokinetic studies will be needed to inform the development of such trials.

Cost to perform door-to-door universal sputum screening for TB in a high-burden community

BACKGROUND: Population-based active case-finding (ACF) identifies people with TB in communities but can be costly.METHODS: We conducted an empiric costing study within a door-to-door household ACF campaign in an urban community in Uganda, where all adults, regardless of symptoms, were screened by sputum Xpert Ultra testing. We used a combination of direct observation and self-reported logs to estimate staffing requirements. Study budgets were reviewed to collect costs of overheads, equipment, and consumables. Our primary outcome was the cost per person diagnosed with TB.RESULTS: Over a 28-week period, three teams of two people collected sputum from 11,341 adults, of whom 48 (0.4%) tested positive for TB. Screening 1,000 adults required 258 person-hours of effort at a cost of US$402,000, 70% of which was for GeneXpert cartridges. The estimated cost per person screened was $36 (95% uncertainty range [95% UR] 34-38), and the cost per person diagnosed with Xpert-positive TB was $8,400 (95% UR 8,000-8,900). The prevalence of TB in the underlying community was the primary modifiable determinant of the cost per person diagnosed.CONCLUSION: Door-to-door screening can be feasibly performed at scale, but will require effective triage and identification of high-prevalence populations to be affordable and cost-effective.

Methods for measuring short-term geographical mobility used in infectious disease research: a scoping review protocol

INTRODUCTION

Geographical mobility, the movement of individuals or populations, may increase an individual's risk of acquiring or transmitting infectious diseases, including HIV, tuberculosis, malaria and COVID-19. Many studies have collected information on short-term mobility through self-reported travel histories or using GPS trackers, but there has been no consistent conceptualisation and operationalisation of such geographical mobility in global health research. This protocol aims to describe and synthesise different approaches to measuring short-term mobility.

METHODS AND ANALYSIS

We will search three databases (PubMed, Embase and Global Health) for peer-reviewed articles. After removing duplicates, two reviewers will first screen the titles and abstracts and then proceed to full-text screening. We will include studies that measure mobility at the individual level in the context of infectious diseases, including clinical trials, epidemiological studies and analyses of register data. Additional articles for inclusion may be identified through review of references in selected papers. We will summarise the method of data collection (GPS trackers, cellphones, retrospective self-report, travel journal, etc) and the specific measures used (overnight travel, having a secondary residence, travel outside of district, etc).

ETHICS AND DISSEMINATION

This study consists of reviewing and abstracting existing data from publicly available materials, and therefore does not require ethical approval. The results of this study will be submitted for peer reviewed publication and may be presented at a relevant global health conference.

Geographic distribution and predictors of diagnostic delays among possible TB patients in Uganda

BACKGROUND

Understanding the geographic distribution and factors associated with delayed TB diagnosis may help target interventions to reduce delays and improve patient outcomes.

METHODS

We conducted a secondary analysis of adults undergoing TB evaluation within a public health demonstration project in Uganda. Using Global Moran's I (GMI) and Getis-Ord GI* statistics, we evaluated for residential clustering and hotspots associated with patient-related and health system-related delays. We performed multivariate logistic regression to identify individual predictors of both types of delays.

RESULTS

Of 996 adults undergoing TB evaluation (median age: 37 years, IQR 28-49), 333 (33%) experienced patient delays, and 568 (57%) experienced health system delays. Participants were clustered (GMI 0.47-0.64, P ⩽ 0.001) at the sub-county level, but there were no statistically significant hotspots for patient or health system delays. Married individuals were less likely to experience patient delays (OR 0.6, 95% CI 0.48-0.75; P < 0.001). Those aged 38-57 years (OR 1.2, 95% CI 1.07-1.38; P = 0.002) were more likely than those aged ⩾58 years to experience patient delays. Knowledge about TB (OR 0.8, 95% CI 0.63-0.98; P = 0.03) protected against health system delays.

CONCLUSIONS

We did not identify geographic hotspots for TB diagnostic delays. Instead, delays were associated with individual factors such as age, marital status and TB knowledge.