National population-based tuberculosis prevalence survey in Ghana, 2013

Subclinical tuberculosis: a meta-analysis of prevalence and scoping review of definitions, prevalence and clinical characteristics

BACKGROUND

This scoping review aimed to characterise definitions used to describe subclinical tuberculosis (TB), estimate the prevalence in different populations and describe the clinical characteristics and treatment outcomes in the scientific literature.

METHODS

A systematic literature search was conducted using PubMed. We included studies published in English between January 1990 and August 2022 that defined "subclinical" or "asymptomatic" pulmonary TB disease, regardless of age, HIV status and comorbidities. We estimated the weighted pooled proportions of subclinical TB using a random-effects model by World Health Organization reported TB incidence, populations and settings. We also pooled the proportion of subclinical TB according to definitions described in published prevalence surveys.

RESULTS

We identified 29 prevalence surveys and 71 other studies. Prevalence survey data (2002-2022) using "absence of cough of any duration" criteria reported higher subclinical TB prevalence than those using the stricter "completely asymptomatic" threshold. Prevalence estimates overlap in studies using other symptoms and cough duration. Subclinical TB in studies was commonly defined as asymptomatic TB disease. Higher prevalence was reported in high TB burden areas, community settings and immunocompetent populations. People with subclinical TB showed less extensive radiographic abnormalities, higher treatment success rates and lower mortality, although studies were few.

CONCLUSION

A substantial proportion of TB is subclinical. However, prevalence estimates were highly heterogeneous between settings. Most published studies incompletely characterised the phenotype of people with subclinical TB. Standardised definitions and diagnostic criteria are needed to characterise this phenotype. Further research is required to enhance case finding, screening, diagnostics and treatment options for subclinical TB.

Evaluation of treatment outcomes among adult patients diagnosed with tuberculosis in Ghana: A 10 year retrospective review

Objectives

The study determined tuberculosis (TB) treatment outcomes in Southern Ghana from 2012 to 2021.

Methods

A retrospective analysis of service data on TB cases was conducted. Treatment success was defined as TB cure or completion of treatment course, whereas unsuccessful outcomes was defined as death, failure of treatment and lost to follow up. Bivariate and multivariate logistic regression was used to determine factors associated with treatment outcomes.

Results

A total of 4106 adult TB cases were reported with a median age of 41 (interquartile range 32-52) years. Of these, 93.1% (n = 3823) were newly diagnosed. The treatment success rate declined from 71.0% in 2012 to 55.7% in 2021 (ktau-b = -0.56, P = 0.0318). Clinically diagnosed TB and extra-pulmonary TB had 7.0% (adjusted prevalence ratio [aPR]: 0.93, 95% confidence interval [CI]: 0.88-1.00) and 24.0% (aPR: 0.76, 95% CI: 0.69-0.84) respectively, less successful treatment outcome compared to pulmonary TB patients. HIV negative status was associated with 22% higher successful treatment outcome compared with being HIV positive (aPR: 1.22, 95% CI: 1.12-1.33).

Conclusion

Tuberculosis treatment success rate declined over the period. There is a need for the TB Control Programme to review the national and sub-national TB data to ascertain poor performing TB treatment sites to identify and address context specific challenges with treatment interventions and system inadequacies to improve treatment success rates.

Geographic availability of and physical accessibility to tuberculosis diagnostic tests in Ghana: a cross-sectional survey

BACKGROUND

In Ghana, tuberculosis (TB) case detection is low (< 34%). Existing scientific evidence suggest access to TB diagnostic tests play an essential role in TB case detection, yet little has been scientifically documented on it in Ghana. This study, therefore, sought to map TB diagnosis sites, and describe the geographic availability and physical accessibility to TB diagnosis in six regions of Ghana to inform scale-up and future placement of TB diagnostic tests.

METHODS

We assembled the geolocation and attribute data of all health facilities offering TB diagnosis in Upper West Region (UWR), Upper East Region (UER), Ahafo, North-East, Northern, and Savannah regions. QGIS was employed to estimate the distance and travel time to TB diagnosis sites within regions. Travel time estimates were based on assumed motorised tricycle speed of 20 km (km)/hour.

RESULTS

Of the total 1584 health facilities in the six regions, 86 (5.4%) facilities were providing TB diagnostic testing services. This 86 TB diagnosis sites comprised 56 (65%) microscopy sites, 23 (27%) both microscopy and GeneXpert sites, and 7 (8%) GeneXpert only sites (8%). Of the 86 diagnosis sites, 40 (46%) were in the UER, follow by Northern Region with 16 (19%), 12 (14%) in UWR, 9 (10%) in Ahafo Region, 5 (6%) in North East, and 4 (5%) in Savannah Region. The overall estimated mean distance and travel time to the nearest TB diagnosis site was 23.3 ± 13.8 km and 67.6 ± 42.6 min respectively. Savannah Region recorded the longest estimated mean distance and travel time with 36.1 ± 14.6 km and 108.3 ± 43.9 min, whilst UER recorded the shortest with 10.2 ± 5.8 km and 29.1 ± 17.4 min. Based on a 10 km buffer of settlement areas, an estimated 75 additional TB diagnosis sites will be needed to improve access to TB diagnosis services across the six regions.

CONCLUSION

This study highlights limited availability of TB diagnosis sites and poor physical accessibility to TB diagnosis sites across five out of the six regions. Targeted implementation of additional TB diagnosis sites is needed to reduce travel distances to ≤ 10 km.

Bidirectional screening and testing for TB and COVID-19 among outpatient department attendees: outcome of an initial intervention in Ghana

BACKGROUND

Tuberculosis (TB) remains a major public health threat in Ghana. The impact of COVID-19 resulted in a 15% decline of TB case notification in 2020 compared to 2019. To mitigate the impact on TB services, the Ghana National Tuberculosis Programme (NTP) introduced the bidirectional screening and testing for TB and COVID-19 in 2021.

OBJECTIVE

To evaluate the yield of bidirectional screening and testing for TB and COVID-19 among facility attendees in the Greater Accra region.

METHOD

We used secondary data obtained from the initial implementation stage of the bidirectional testing for TB and COVID-19 among COVID-19 and/or TB presumed cases in five health facilities in the Greater Accra Region from January to March 2021. To mitigate the impact of COVID-19 on TB services and accelerate TB case detection, the NTP of Ghana introduced bidirectional screening and testing for TB and COVID-19 in Greater Accra Region before scaling up at national level.

RESULTS

A total of 208 presumed TB or COVID-19 cases were identified: 113 were tested for COVID-19 only, and 94 were tested for both TB and COVID-19, 1 was tested for TB only. Among presumed cases tested for COVID-19, 9.7% (95% CI, 5.6-13.7%) were tested positive. Whilst among the total presumed tested for TB, 13.7% (95% CI, 6.8-20.6%) were confirmed to have TB. Among the total 94 presumed cases tested for both TB and COVID-19, 11.7% (95% CI, 5.2-18.2%) were confirmed to have TB and 13.8% (95% CI, 6.9-20.8%) participants were COVID-19 positive and one participant (1.1%) had both COVID-19 and TB.

CONCLUSION

Bidirectional screening and testing for TB and COVID-19 shows significant potential for improving overall case detection for the two diseases. The bidirectional screening and testing could be applicable to address a similar respiratory epidemic in the future that might have a masking effect on the response to TB disease.

The in-hospital tuberculosis diagnostic cascade and early clinical outcomes among people living with HIV before and during the COVID-19 pandemic - a prospective multisite cohort study from Ghana

OBJECTIVES

The COVID-19 pandemic had a disruptive impact on tuberculosis (TB) and HIV services. We assessed the in-hospital TB diagnostic care among people with HIV (PWH) overall and before and during the pandemic.

METHODS

In this prospective study, adult PWH admitted at three hospitals in Ghana were recruited if they had a positive World Health Organization four-symptom screen or one or more World Health Organization danger signs or advanced HIV. We collected data on patient characteristics, TB assessment, and clinical outcomes after 8 weeks and used descriptive statistics and survival analysis.

RESULTS

We enrolled 248 PWH with a median clusters of differentiation 4 count of 80.5 cells/mm³ (interquartile range 24-193). Of those, 246 (99.2%) patients had a positive World Health Organization four-symptom screen. Overall, 112 (45.2%) patients obtained a sputum Xpert result, 66 (46.5%) in the prepandemic and 46 (43.4%) in the pandemic period; P-value = 0.629. The TB prevalence of 46/246 (18.7%) was similar in the prepandemic 28/140 (20.0%) and pandemic 18/106 (17.0%) population; P-value = 0.548. The 8-week all-cause mortality was 62/246 (25.2%), with no difference in cumulative survival when stratifying for the pandemic period; log-rank P-value = 0.412.

CONCLUSION

The study highlighted a large gap in the access to TB investigation and high early mortality among hospitalized PWH, irrespective of the COVID-19 pandemic.

Barriers and motivation for presumptive tuberculosis case referral: qualitative analysis among operators of community medicine outlets in Ghana

Background

Community medicine outlets (CMOs) are the first point of call for individuals presenting with cough in Ghana. Although operators of CMOs comprising pharmacists and over-the-counter (OTC) medicine sellers largely support the public–private mix strategy which seeks to engage pharmacies in tuberculosis (TB) case detection, a significant proportion is not involved in TB referral services. The study explores the barriers to and motivation for presumptive TB case referral among CMO operators.

Methods

We used open- and close-ended questions nested in a telephone survey which assessed factors associated with presumptive TB case referral among CMO operators (n = 465). We interviewed participants using computer assisted telephone interviews and analysed the qualitative data using adjusted Mayring’s structured qualitative content analysis.

Results

Based on participants’ own experiences, non-referral was attributed to negative attitudes of presumed cases (48.2%) and inability to meet the financial demands of referred presumed cases (26.3%). Regarding their perception of barriers to TB referral for their professional colleagues, an assumed lack of TB training (44.5%) and an assumed negative attitude of operators (43.6%) were mentioned. From close-ended questions, most chosen barriers to referral were: the assumption of not having seen a presumptive TB case yet (31.8%), lack of TB training (22.2%) and no monetary motivation for operators (10.5%). Most operators (81.6%) view TB referral services as their social responsibility and feel self-motivated to refer cases in order to control the spread of TB in their communities. Of 152 further comments extracted as recommendations to improve referral, 101 (66.4%) of respondents would only refer with the availability of support systems in the form of TB training and making TB diagnostic testing more accessible.

Conclusion

Operators of CMOs are predominantly self-motivated to refer presumptive TB cases. Barriers to referral might be mitigated by providing more training to operators and specific financial support such as reimbursement of travel costs to presumptive cases.

Perceptions, Attitudes, Experiences and Opinions of Tuberculosis Associated Stigma: A Qualitative Study of the Perspectives among the Bolgatanga Municipality People of Ghana

Tuberculosis (TB) is the tenth leading cause of death worldwide. About 1.3 million people die from TB each year, and most of them are in developing countries. The stigma associated with TB is a barrier to seeking treatment and adequate care. It causes a delay in treatment-seeking and diagnosis and thus decreases the likelihood of being cured and ultimately leads to death. The objective of this study was to explore the perceptions, attitudes, experiences, and opinions about stigma related to TB among adults infected with TB and adults who were not infected with TB. Our study was qualitative in nature. The study was conducted in the community of Bolgatanga municipality of the upper-east region of Ghana. Three focus group discussions (FGDs) were conducted; one with six TB-infected females, one with seven TB-infected males, and one with six non-TB-infected participants. Data were analyzed using qualitative content analysis and presented in pre-defined and/or emerging themes: perception about signs and symptoms observed by TB infected person, attitudes towards TB patients before and after diagnosis, reasons for stigmatization, perception about diagnostic testing, and taking the drugs. Transcripts of the discussions were read, and a list of meanings for units, codes, and themes was generated on the research question. We identified the existence of stigma associated with TB. TB-infected male patients had more autonomy in decision-making about receiving treatment and other family matters compared to female TB patients. TB-infected women suffered more economic vulnerability due to the loss of their work, and the stigma was worsened due to delayed diagnosis and treatment, and they were regarded as liabilities rather than assets. TB-infected patients became stigmatized because non-TB-infected community participants did not want to come into close contact with them. Our findings suggest heightening of advocacy, communication, social mobilization, and health education on TB in the community of Bolgatanga municipality is needed to allay TB-related stigma, especially for women.

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.

Barriers to tuberculosis case finding in primary and secondary health facilities in Ghana: perceptions, experiences and practices of healthcare workers

BACKGROUND

Ghana's national tuberculosis (TB) prevalence survey conducted in 2013 showed higher than expected TB prevalence indicating that many people with TB were not being identified and treated. Responding to this, we assessed barriers to TB case finding from the perspective, experiences and practices of healthcare workers (HCWs) in rural and urban health facilities in the Volta region, Ghana.

METHODS

We conducted structured clinic observations and in-depth interviews with 12 HCWs (including five trained in TB case detection) in four rural health facilities and a municipal hospital. Interview transcripts and clinic observation data were manually organised, triangulated and analysed into health system-related and HCW-related barriers.

RESULTS

The key health system barriers identified included lack of TB diagnostic laboratories in rural health facilities and no standard referral system to the municipal hospital for further assessment and TB testing. In addition, missed opportunities for early diagnosis of TB were driven by suboptimal screening practices of HCWs whose application of the national standard operating procedures (SOP) for TB case detection was inconsistent. Further, infection prevention and control measures in health facilities were not implemented as recommended by the SOP. HCW-related barriers were mainly lack of training on case detection guidelines, fear of infection (exacerbated by lack of appropriate personal protective equipment [PPE]) and lack of motivation among HCWs for TB work. Solutions to these barriers suggested by HCWs included provision of at least one diagnostic facility in each sub-municipality, provision of transport subsidies to enable patients' travel for testing, training of newly-recruited staff on case detection guidelines, and provision of appropriate PPE.

CONCLUSION

TB case finding was undermined by few diagnostic facilities; inconsistent referral mechanisms; poor implementation, training and quality control of a screening tool and guidelines; and HCWs fearing infection and not being motivated. We recommend training for and quality monitoring of TB diagnosis and treatment with a focus on patient-centred care, an effective sputum transport system, provision of the TB symptom screening tool and consistent referral pathways from peripheral health facilities.

Active tuberculosis case findings in Ghanaian health facilities: effectiveness and sensitivity of the symptoms-based screening tool

Introduction

the National Tuberculosis Programme (NTP), Ghana, introduced Symptoms-Based Screening (SBS) Tool for TB case finding. This study aimed to determine the challenges and limitations associated with the use of the SBS Tool for active tuberculosis case finding in Ghanaian health facility settings.

Methods

this study targeted suspected TB patients attending two health facilities in the Ho Municipality, Ghana. Initially, suspected TB patients were screened with the SBS tool and presumptive patients subsequently tested for M. tuberculosis using microscopy and geneXpert assay. Additionally, health personnel were interviewed to assess the user-friendliness, challenges, and limitations associated with the tool.

Results

of 636 presumptive TB patients identified, 1.73% had tuberculosis. Coughing for > 2 weeks (χ²=24.8; p<0.05); chest pain (χ²=28.3; p<0.01) and night sweat (χ²=34.8; p<0.05) associated significantly with M. tuberculosis infection status. The health personnel found the tool to be not user-friendly and it also lacked indicators to identify other vulnerable individuals such as diabetics, cigarette smokers, alcoholics, immunocompromised, and malnourished individuals. Therefore, the SBS tool was found not to be sensitive enough to identify probable cases.

Conclusion

the SBS tool is useful for detecting active TB cases, however, it must be improved to identify vulnerable individuals such as diabetics, immunosuppressed, and malnourished.

Case finding of tuberculosis among mining communities in Ghana

Background

Data on active TB case finding activities among artisanal gold mining communities (AMC) is limited. The study assessed the yield of TB cases from the TB screening activities among AMC in Ghana, the factors associated with TB in these communities and the correlation between the screening methods and a diagnosis of TB.

Methods

We conducted secondary data analyses of NTP program data collected from TB case finding activities using symptom screening and mobile X-ray implemented in hard to reach AMC. Yield of TB cases, number needed to screen (NNS) and the number needed to test (NNT) to detect a TB case were assessed and logistic regression were conducted to assess factors associated with TB. The performance of screening methods chest X-ray and symptoms in the detection of TB cases was also evaluated.

Results

In total 10,441 people from 78 communities in 24 districts were screened, 55% were female and 60% (6,296) were in the aged 25 to 54 years. Ninety-five TB cases were identified, 910 TB cases per 100,000 population screened; 5.6% of the TB cases were rifampicin resistant. Being male (aOR 5.96, 95% CI 3.25–10.92, P < 0.001), a miner (aOR 2.70, 95% CI 1.47–4.96, P = 0.001) and age group 35 to 54 years (aOR 2.27, 95% CI 1.35–3.84, P = 0.002) were risk factors for TB. NNS and NNT were 110 and 24 respectively.; Cough of any duration had the strongest association with X-ray suggestive of TB with a correlation coefficient of 0.48. Cough was most sensitive for a diagnosis of TB; sensitivity of 86.3% (95% CI 79.4–93.2) followed by X-ray, sensitivity 81.1% (95% CI 71.7–88.4). The specificities of the symptoms and X-rays ranged from 80.2% (cough) to 97.3% (sputum).

Conclusion

The high risk of TB in the artisanal mining communities and in miners in this study reinforces the need to target these populations with outreach programs particularly in hard to reach areas. The diagnostic value of cough highlights the usefulness of symptom screening in this population that may be harnessed even in the absence of X-ray to identify those suspected to have TB for further evaluation.

Knowledge, attitude and practice towards tuberculosis in Gambia: a nation-wide cross-sectional survey

Background

Early diagnosis and treatment of tuberculosis (TB) are the mainstay of global and national TB control efforts. However, the gap between expected and reported cases persists for various reasons attributable to the TB services and care-seeking sides of the TB care cascade. Understanding individual and collective perspectives of knowledge, attitudes, beliefs and other social circumstances around TB can inform an evidence-based approach in engaging communities and enhance their participation in TB case detection and treatment.

Methods

The study was conducted during the Gambian survey of TB prevalence. This was a nationwide cross-sectional multistage cluster survey with 43,100 participants aged ≥15 years in 80 clusters. The study sample, a random selection of 10% of the survey population within each cluster responded to a semi-structured questionnaire administered by trained fieldworkers to assess the knowledge, attitudes and practice of the participants towards TB. Overall knowledge, attitude and practice scores were dichotomised using the computed mean scores and analysed using descriptive, univariable and multivariable logistic regression.

Results

All targeted participants (4309) were interviewed. Majority were females 2553 (59.2%), married 2614 (60.7%), had some form of education 2457 (57%), and were unemployed 2368 (55%). Although 3617 (83.9%) of the participants had heard about TB, only 2883 (66.9%) were considered to have good knowledge of TB. Overall 3320 (77%) had unfavourable attitudes towards TB, including 1896 (44%) who indicated a preference for staying away from persons with TB rather than helping them. However, 3607(83.7%) appeared to have the appropriate health-seeking behaviours with regard to TB as 4157 (96.5%) of them were willing to go to the health facility if they had symptoms suggestive of TB.

Conclusions

About 3 in 10 Gambians had poor knowledge on TB, and significant stigma towards TB and persons with TB persists. Interventions to improve TB knowledge and address stigma are required as part of efforts to reduce the burden of undiagnosed TB in the country.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12889-020-09685-3.

National tuberculosis prevalence surveys in Africa, 2008-2016: an overview of results and lessons learned

OBJECTIVE AND METHODS

Worldwide, tuberculosis (TB) is the leading cause of death from a single infectious agent. In many countries, national TB prevalence surveys are the only way to reliably measure the burden of TB disease and can also provide other evidence to inform national efforts to improve TB detection and treatment. Our objective was to synthesise the results and lessons learned from national surveys completed in Africa between 2008 and 2016, to complement a previous review for Asia.

RESULTS

Twelve surveys completed in Africa were identified: Ethiopia (2010-2011), Gambia (2011-2013), Ghana (2013), Kenya (2015-2016), Malawi (2013-2014), Nigeria (2012), Rwanda (2012), Sudan (2013-2014), Tanzania (2011-2012), Uganda (2014-2015), Zambia (2013-2014) and Zimbabwe (2014). The eligible population in all surveys was people aged ≥15 years who met residency criteria. In total 588 105 individuals participated, equivalent to 82% (range 57-96%) of those eligible. The prevalence of bacteriologically confirmed pulmonary TB disease in those ≥15 years varied from 119 (95% CI 79-160) per 100 000 population in Rwanda and 638 (95% CI 502-774) per 100 000 population in Zambia. The male:female ratio was 2.0 overall, ranging from 1.2 (Ethiopia) to 4.1 (Uganda). Prevalence per 100 000 population generally increased with age, but the absolute number of cases was usually highest among those aged 35-44 years. Of identified TB cases, 44% (95% CI 40-49) did not report TB symptoms during screening and were only identified as eligible for diagnostic testing due to an abnormal chest X-ray. The overall ratio of prevalence to case notifications was 2.5 (95% CI 1.8-3.2) and was consistently higher for men than women. Many participants who did report TB symptoms had not sought care; those that had were more likely to seek care in a public health facility. HIV prevalence was systematically lower among prevalent cases than officially notified TB patients with an overall ratio of 0.5 (95% CI 0.3-0.7). The two main study limitations were that none of the surveys included people <15 years, and 5 of 12 surveys did not have data on HIV status.

CONCLUSIONS

National TB prevalence surveys implemented in Africa between 2010 and 2016 have contributed substantial new evidence about the burden of TB disease, its distribution by age and sex, and gaps in TB detection and treatment. Policies and practices to improve access to health services and reduce under-reporting of detected TB cases are needed, especially among men. All surveys provide a valuable baseline for future assessment of trends in TB disease burden.