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1.
PLoS One ; 19(5): e0291215, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38787869

RESUMEN

Tuberculosis (TB) transmission and prevalence are dynamic over time, and heterogeneous within populations. Public health programmes therefore require up-to-date, accurate epidemiological data to appropriately allocate resources, target interventions, and track progress towards End TB goals. Current methods of TB surveillance often rely on case notifications, which are biased by access to healthcare, and TB disease prevalence surveys, which are highly resource-intensive, requiring many tens of thousands of people to be tested to identify high-risk groups or capture trends. Surveys of "latent TB infection", or immunoreactivity to Mycobacterium tuberculosis (Mtb), using tests such as interferon-gamma release assays (IGRAs) could provide a way to identify TB transmission hotspots, supplementing information from disease notifications, and with greater spatial and temporal resolution than is possible to achieve in disease prevalence surveys. This cross-sectional survey will investigate the prevalence of Mtb immunoreactivity amongst young children, adolescents and adults in Blantyre, Malawi, a high HIV-prevalence city in southern Africa. Through this study we will estimate the annual risk of TB infection (ARTI) in Blantyre and explore individual- and area-level risk factors for infection, as well as investigating geospatial heterogeneity of Mtb infection (and its determinants), and comparing these to the distribution of TB disease case-notifications. We will also evaluate novel diagnostics for Mtb infection (QIAreach QFT) and sampling methodologies (convenience sampling in healthcare settings and community sampling based on satellite imagery), which may increase the feasibility of measuring Mtb infection at large scale. The overall aim is to provide high-resolution epidemiological data and provide new insights into methodologies which may be used by TB programmes globally.


Asunto(s)
Mycobacterium tuberculosis , Tuberculosis , Malaui/epidemiología , Humanos , Estudios Transversales , Mycobacterium tuberculosis/inmunología , Adulto , Adolescente , Tuberculosis/epidemiología , Tuberculosis/diagnóstico , Prevalencia , Niño , Femenino , Masculino , Ensayos de Liberación de Interferón gamma/métodos , Adulto Joven , Factores de Riesgo
2.
PLOS Glob Public Health ; 4(2): e0002596, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38422092

RESUMEN

Tuberculosis (TB) and non-communicable diseases (NCD) share predisposing risk factors. TB-associated NCD might cluster within households affected with TB requiring shared prevention and care strategies. We conducted an individual participant data meta-analysis of national TB prevalence surveys to determine whether NCD cluster in members of households with TB. We identified eligible surveys that reported at least one NCD or NCD risk factor through the archive maintained by the World Health Organization and searching in Medline and Embase from 1 January 2000 to 10 August 2021, which was updated on 23 March 2023. We compared the prevalence of NCD and their risk factors between people who do not have TB living in households with at least one person with TB (members of households with TB), and members of households without TB. We included 16 surveys (n = 740,815) from Asia and Africa. In a multivariable model adjusted for age and gender, the odds of smoking was higher among members of households with TB (adjusted odds ratio (aOR) 1.23; 95% CI: 1.11-1.38), compared with members of households without TB. The analysis did not find a significant difference in the prevalence of alcohol drinking, diabetes, hypertension, or BMI between members of households with and without TB. Studies evaluating household-wide interventions for smoking to reduce its dual impact on TB and NCD may be warranted. Systematically screening for NCD using objective diagnostic methods is needed to understand the actual burden of NCD and inform comprehensive interventions.

3.
PLOS Glob Public Health ; 3(12): e0002683, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38051717

RESUMEN

Active case-finding (ACF) for tuberculosis can help find the "missing millions" with undiagnosed tuberculosis. In a cluster-randomised trial, we investigated impact of ACF on case-notifications in Blantyre, Malawi, where ACF has been intensively implemented following 2014 estimates of ~1,000 per 100,000 adults with undiagnosed TB. Following a pre-intervention prevalence survey (May 2019 to March 2020), constrained randomisation allocated neighbourhoods to either door-to-door ACF (sputum microscopy for reported cough >2 weeks) or standard-of-care (SOC). Implementation was interrupted by COVID-19. Cluster-level bacteriologically-confirmed case-notification rate (CNR) ratio within 91 days of ACF was our redefined primary outcome; comparison between arms used Poisson regression with random effects. Secondary outcomes were 91-day CNR ratios comparing all tuberculosis registrations and all non-ACF registrations. Interrupted time series (ITS) analysis of CNRs in the SOC arm examined prevalence survey impact. (ISRCTN11400592). 72 clusters served by 10 study-supported tuberculosis registration centres were randomised to ACF (261,244 adults, 58,944 person-years follow-up) or SOC (256,713 adults, 52,805 person-years). Of 1,192 ACF participants, 13 (1.09%) were smear-positive. Within 91 days, 113 (42 bacteriologically-confirmed) and 108 (33 bacteriologically-confirmed) tuberculosis patients were identified as ACF or SOC cluster residents, respectively. There was no difference by arm, with adjusted 91-day CNR ratios 1.12 (95% CI: 0.61-2.07) for bacteriologically-confirmed tuberculosis; 0.93 (95% CI: 0.68-1.28) for all tuberculosis registrations; and 0.86 (95%CI: 0.63-1.16) for non-ACF (routinely) diagnosed. Of 7,905 ACF and 7,992 SOC pre-intervention survey participants, 12 (0.15%) and 17 (0.21%), respectively, had culture/Xpert-confirmed tuberculosis. ITS analysis showed no survey impact on SOC CNRs. Despite residual undiagnosed tuberculosis of 150 per 100,000 population, there was no increase in tuberculosis notifications from this previously successful approach targeting symptomatic disease, likely due to previous TB ACF and rapid declines in TB burden. In such settings, future ACF should focus on targeted outreach and demand creation, alongside optimised facility-based screening. Trial Registration: ISRCTN11400592.

4.
PLOS Glob Public Health ; 3(10): e0001911, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37862284

RESUMEN

Recent evidence shows rapidly changing tuberculosis (TB) epidemiology in Southern and Eastern Africa, with need for subdistrict prevalence estimates to guide targeted interventions. We conducted a pulmonary TB prevalence survey to estimate current TB burden in Blantyre city, Malawi. From May 2019 to March 2020, 115 households in middle/high-density residential Blantyre, were randomly-selected from each of 72 clusters. Consenting eligible participants (household residents ≥ 18 years) were interviewed, including for cough (any duration), and offered HIV testing and chest X-ray; participants with cough and/or abnormal X-ray provided two sputum samples for microscopy, Xpert MTB/Rif and mycobacterial culture. TB disease prevalence and risk factors for prevalent TB were calculated using complete-case analysis, multiple imputation, and inverse probability weighting. Of 20,899 eligible adults, 15,897 (76%) were interviewed, 13,490/15,897 (85%) had X-ray, and 1,120/1,394 (80%) sputum-eligible participants produced at least one specimen, giving 15,318 complete cases (5,895, 38% men). 29/15,318 had bacteriologically-confirmed TB (189 per 100,000 complete-case (cc) / 150 per 100,000 with inverse weighting (iw)). Men had higher burden (cc: 305 [95% CI:144-645] per 100,000) than women (cc: 117 [95% CI:65-211] per 100,000): cc adjusted odds ratio (aOR) 2.70 (1.26-5.78). Other significant risk factors for prevalent TB on complete-case analysis were working age (25-49 years) and previous TB treatment, but not HIV status. Multivariable analysis of imputed data was limited by small numbers, but previous TB and age group 25-49 years remained significantly associated with higher TB prevalence. Pulmonary TB prevalence for Blantyre was considerably lower than the 1,014 per 100,000 for urban Malawi in the 2013-14 national survey, at 150-189 per 100,000 adults, but some groups, notably men, remain disproportionately affected. TB case-finding is still needed for TB elimination in Blantyre, and similar urban centres, but should focus on reaching the highest risk groups, such as older men.

5.
EClinicalMedicine ; 63: 102191, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37680950

RESUMEN

Background: Non-communicable diseases (NCDs) and NCD risk factors, such as smoking, increase the risk for tuberculosis (TB). Data are scarce on the risk of prevalent TB associated with these factors in the context of population-wide systematic screening and on the association between NCDs and NCD risk factors with different manifestations of TB, where ∼50% being asymptomatic but bacteriologically positive (subclinical). We did an individual participant data (IPD) meta-analysis of national and sub-national TB prevalence surveys to synthesise the evidence on the risk of symptomatic and subclinical TB in people with NCDs or risk factors, which could help countries to plan screening activities. Methods: In this systematic review and IPD meta-analysis, we identified eligible prevalence surveys in low-income and middle-income countries that reported at least one NCD (e.g., diabetes) or NCD risk factor (e.g., smoking, alcohol use) through the archive maintained by the World Health Organization and by searching in Medline and Embase from January 1, 2000 to August 10, 2021. The search was updated on March 23, 2023. We performed a one-stage meta-analysis using multivariable multinomial models. We estimated the proportion of and the odds ratio for subclinical and symptomatic TB compared to people without TB for current smoking, alcohol use, and self-reported diabetes, adjusted for age and gender. Subclinical TB was defined as microbiologically confirmed TB without symptoms of current cough, fever, night sweats, or weight loss and symptomatic TB with at least one of these symptoms. We assessed heterogeneity using forest plots and I2 statistic. Missing variables were imputed through multi-level multiple imputation. This study is registered with PROSPERO (CRD42021272679). Findings: We obtained IPD from 16 national surveys out of 21 national and five sub-national surveys identified (five in Asia and 11 in Africa, N = 740,815). Across surveys, 15.1%-56.7% of TB were subclinical (median: 38.1%). In the multivariable model, current smoking was associated with both subclinical (OR 1.67, 95% CI 1.27-2.40) and symptomatic TB (OR 1.49, 95% CI 1.34-1.66). Self-reported diabetes was associated with symptomatic TB (OR 1.67, 95% CI 1.17-2.40) but not with subclinical TB (OR 0.92, 95% CI 0.55-1.55). For alcohol drinking ≥ twice per week vs no alcohol drinking, the estimates were imprecise (OR 1.59, 95% CI 0.70-3.62) for subclinical TB and OR 1.43, 95% CI 0.59-3.46 for symptomatic TB). For the association between current smoking and symptomatic TB, I2 was high (76.5% (95% CI 62.0-85.4), while the direction of the point estimates was consistent except for three surveys with wide CIs. Interpretation: Our findings suggest that current smokers are more likely to have both symptomatic and subclinical TB. These individuals can, therefore, be prioritised for intensified screening, such as the use of chest X-ray in the context of community-based screening. People with self-reported diabetes are also more likely to have symptomatic TB, but the association is unclear for subclinical TB. Funding: None.

6.
Clin Infect Dis ; 77(1): 94-100, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37099318

RESUMEN

BACKGROUND: Tuberculosis case-finding interventions are critical to meeting World Health Organization End TB strategy goals. We investigated the impact of community-wide tuberculosis active case finding (ACF) alongside scale-up of human immunodeficiency virus (HIV) testing and care on trends in adult tuberculosis case notification rates (CNRs) in Blantyre, Malawi. METHODS: Five rounds of ACF for tuberculosis (1-2 weeks of leafleting, door-to-door enquiry for cough and sputum microscopy) were delivered to neighborhoods ("ACF areas") in North-West Blantyre between April 2011 and August 2014. Many of these neighborhoods also had concurrent HIV testing interventions. The remaining neighborhoods in Blantyre City ("non-ACF areas") provided a non-randomized comparator. We analyzed TB CNRs from January 2009 until December 2018. We used interrupted time series analysis to compare tuberculosis CNRs before ACF and after ACF, and between ACF and non-ACF areas. RESULTS: Tuberculosis CNRs increased in Blantyre concurrently with start of ACF for tuberculosis in both ACF and non-ACF areas, with a larger magnitude in ACF areas. Compared to a counterfactual where pre-ACF CNR trends continued during ACF period, we estimated there were an additional 101 (95% confidence interval [CI] 42 to 160) microbiologically confirmed (Bac+) tuberculosis diagnoses per 100 000 person-years in the ACF areas in 3 and a half years of ACF. Compared to a counterfactual where trends in ACF area were the same as trends in non-ACF areas, we estimated an additional 63 (95% CI 38 to 90) Bac + diagnoses per 100 000 person-years in the same period. CONCLUSIONS: Tuberculosis ACF was associated with a rapid increase in people diagnosed with tuberculosis in Blantyre.


Asunto(s)
Tamizaje Masivo , Tuberculosis , Adulto , Humanos , Malaui/epidemiología , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Ciudades , VIH
7.
PLoS One ; 17(9): e0269219, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36074775

RESUMEN

BACKGROUND: Household contact tracing provides TB screening and TB preventive therapy (TPT) to contacts at high risk of TB disease. However, it is resource intensive, inconvenient, and often poorly implemented. We investigated a novel model aiming to improve uptake. METHODS: Between May and December 2014, we randomised patient with TB who consented to participate in the trial to either standard of care (SOC) or intervention (PACTS) arms. Participants randomised to PACTS received one screening/triage tool (adapted from WHO integrated management of adolescent and adult illnesses [IMAI] guidelines) and sputum pots for each reported household contact. The tool guided participants through symptom screening; TPT (6-months of isoniazid) eligibility; and sputum collection for contacts. Patients randomised to SOC were managed in accordance with national guidelines, that is, they received verbal instruction on who to bring to clinics for investigation using national guidelines. MAIN OUTCOME AND MEASURES: The primary outcome was the proportion of adult contacts receiving treatment for TB within 3 months of randomisation. Secondary outcomes were the proportions of child contacts under age 5 years (U5Y) who were commenced on, and completed, TPT. Data were analyzed by logistic regression with random effects to adjust for household clustering. RESULTS: Two hundred and fourteen index TB participants were block-randomized from two sites (107 PACTS, reporting 418 contacts; and 107 SOC, reporting 420 contacts). Overall, 62.8% of index TB participants were HIV-positive and 52.1% were TB culture-positive. 250 otherwise eligible TB patients declined participation and 6 households (10 PACTS, 6 SOC) were lost to follow-up and were not included in the analysis. By three months, nine contacts (PACTS: 6, [1.4%]; SOC: 3, [0.7%]) had TB diagnosed, with no difference between groups (adjusted odds ratio [aOR]: 2.18, 95% CI: 0.60-7.95). Eligible PACTS contacts (37/96, 38.5%) were more likely to initiate TPT by 3-months compared to SOC contacts (27/101, 26.7%; aOR 2.27, 95% CI: 1.04-4.98). U5Y children in the PACTS arm (47/81 58.0%) were more likely to have initiated TPT before the 3-month visit compared to SOC children (36/89, 41.4%; aOR: 2.31, 95% CI: 1.05-5.06). CONCLUSIONS AND RELEVANCE: A household-centred patient-delivered symptom screen and IPT eligibility assessment significantly increased timely TPT uptake among U5Y children, but did not significantly increase TB diagnosis. This model needs to be optimized for acceptability, given low participation, and investigated in other low resource settings. CLINICAL TRIAL REGISTRATION: TRIAL REGISTRATION NUMBER: ISRCTN81659509 https://www.isrctn.com/ISRCTN81659509?q=&filters=conditionCategory:Respiratory,recruitmentCountry:Malawi,ageRange:Mixed&sort=&offset=1&totalResults=1&page=1&pageSize=10&searchType=basic-search. 19 July 2012.


Asunto(s)
Trazado de Contacto , Tuberculosis , Adolescente , Adulto , Niño , Preescolar , Composición Familiar , Humanos , Isoniazida/uso terapéutico , Malaui/epidemiología , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , Tuberculosis/prevención & control
8.
Trop Med Infect Dis ; 6(2)2021 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-34069332

RESUMEN

When the COVID-19 pandemic was announced in March 2020, there was concern that TB and HIV programme services in Malawi would be severely affected. We set up real-time monthly surveillance of TB and HIV activities in eight health facilities in Lilongwe to see if it was possible to counteract the anticipated negative impact on TB case detection and treatment and HIV testing. Aggregate data were collected monthly during the COVID-19 period (March 2020-February 2021) using an EpiCollect5 application and compared with monthly data collected during the pre-COVID-19 period (March 2019-February 2020); these reports were sent monthly to programme directors. During COVID-19, there was an overall decrease in persons presenting with presumptive pulmonary TB (45.6%), in patients registered for TB treatment (19.1%), and in individuals tested for HIV (39.0%). For presumptive TB, children and females were more affected, but for HIV testing, adults and males were more affected. During COVID-19, the TB treatment success rate (96.1% in pre-COVID-19 and 96.0% during COVID-19 period) and referral of HIV-positive persons to antiretroviral therapy (100% in pre-COVID-19 and 98.6% during COVID-19 period) remained high and largely unchanged. Declining trends in TB and HIV case detection were not redressed despite real-time monthly surveillance.

9.
Open Forum Infect Dis ; 8(2): ofaa639, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33575422

RESUMEN

BACKGROUND: Diagnosing tuberculosis (TB), the leading cause of death in people with HIV, remains a challenge in resource-limited countries. We assessed TB diagnosis using a strategy that included systematic urine lipoarabinomannan (LAM) testing for all HIV patients hospitalized in medical wards and 6-month mortality according to LAM results. METHODS: This prospective, observational study included adult HIV patients hospitalized in the medical wards of a public district hospital in Malawi regardless of their TB symptoms or CD4 count. Each patient had a clinical examination, and Alere Determine TB-LAM, sputum microscopy, sputum GeneXpert MTB/RIF (Xpert), chest x-ray, and CD4 count were systematically requested. RESULTS: Among 387 inpatients, 54% had a CD4 <200 cells/µL, 64% had presumptive TB, and 90% had ≥1 TB symptom recorded in their medical file. LAM results were available for 99.0% of patients, microscopy for 62.8%, and Xpert for 60.7%. In total, 26.1% (100/383) had LAM-positive results, 48% (48/100) of which were grades 2-4. Any TB laboratory test result was positive in 30.8% (119/387). Among patients with no Xpert result, 28.5% (43/151) were LAM-positive. Cumulative 6-month mortality was 40.1% (151/377): 50.5% (49/97) in LAM-positives and 36.2% (100/276) in LAM-negatives (P = .013). In multivariable regression analyses, LAM-positive patients had a higher risk of mortality than LAM-negatives (adjusted odds ratio, 2.5; 95% CI, 1.1-5.8; P = .037). CONCLUSIONS: In resource-limited hospital medical wards with high TB prevalence, a diagnostic strategy including systematic urine LAM testing for all HIV patients is an easily implementable strategy that identifies a large proportion of patients with TB at risk of death.

10.
Front Public Health ; 8: 551308, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33324593

RESUMEN

Background: Pellagra is caused by niacin (vitamin B3) deficiency and manifested by a distinctive dermatitis. Isoniazid is critical for treating tuberculosis globally and is a component of most regimens to prevent tuberculosis. Isoniazid may contribute to pellagra by disrupting intracellular niacin synthesis. In 2017, Malawian clinicians recognized a high incidence of pellagra-like rashes after scale-up of isoniazid preventive treatment (IPT) to people living with HIV (PLHIV). This increase in pellagra incidence among PLHIV coincided with a seasonal period of sustained food insecurity in the region, which obscured epidemiological interpretations. Although isoniazid has been implicated as a secondary cause of pellagra for decades, no hypothesis-driven epidemiological study has assessed this relationship in a population exposed to isoniazid. We developed this case-control protocol to assess the association between large-scale isoniazid distribution and pellagra in Malawi. Methods: We measure the relative odds of having pellagra among isoniazid-exposed people compared to those without exposure while controlling for other pellagra risk factors. Secondary aims include measuring time from isoniazid initiation to onset of dermatitis, comparing niacin metabolites 1-methylnicotinamide (1-MN), and l-methyl-2-pyridone-5-carboxamide (2-PYR) in urine as a proxy for total body niacin status among subpopulations, and describing clinical outcomes after 30-days multi-B vitamin (containing 300 mg nicotinamide daily) therapy and isoniazid cessation (if exposed). We aim to enroll 197 participants with pellagra and 788 age- and sex-matched controls (1:4 ratio) presenting at three dermatology clinics. Four randomly selected community clinics within 3-25 km of designated dermatology clinics will refer persons with pellagra-like symptoms to one of the study enrollment sites for diagnosis. Trained study dermatologists will conduct a detailed exposure questionnaire and perform anthropometric measurements. A subset of enrollees will provide a casual urine specimen for niacin metabolites quantification and/or point-of-care isoniazid detection to confirm whether participants recently ingested isoniazid. We will use conditional logistic regression, matching age and sex, to estimate odds ratios for the primary study aim. Discussion: The results of this study will inform the programmatic scale-up of isoniazid-containing regimens to prevent tuberculosis.


Asunto(s)
Pelagra , Tuberculosis , Estudios de Casos y Controles , Humanos , Isoniazida/efectos adversos , Malaui/epidemiología , Tuberculosis/epidemiología
11.
J Acquir Immune Defic Syndr ; 85(5): 643-650, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33177475

RESUMEN

BACKGROUND: To assist the Malawi Ministry of Health to evaluate 2 competing strategies for scale-up of isoniazid preventive therapy (IPT) among HIV-positive adults receiving antiretroviral therapy. SETTING: Malawi. METHODS: We used a multidistrict, compartmental model of the Malawi tuberculosis (TB)/HIV epidemic to compare the anticipated health impacts of 6-month versus continuous IPT programs over a 12-year horizon while respecting a US$10.8 million constraint on drug costs in the first 3 years. RESULTS: The 6-month IPT program could be implemented nationwide, whereas the continuous IPT alternative could be introduced in 14 (of the 27) districts. By the end of year 12, the continuous IPT strategy was predicted to avert more TB cases than the 6-month alternative, although not statistically significant (2368 additional cases averted; 95% projection interval [PI], -1459 to 5023). The 6-month strategy required fewer person-years of IPT to avert a case of TB or death than the continuous strategy. For both programs, the mean reductions in TB incidence among people living with HIV by year 12 were expected to be <10%, and the cumulative numbers of IPT-related hepatotoxicity to exceed the number of all-cause deaths averted in the first 3 years. CONCLUSIONS: With the given budgetary constraint, the nationwide implementation of 6-month IPT would be more efficient and yield comparable health benefits than implementing a continuous IPT program in fewer districts. The anticipated health effects associated with both IPT strategies suggested that a combination of different TB intervention strategies would likely be required to yield a greater impact on TB control in settings such as Malawi, where antiretroviral therapycoverage is relatively high.


Asunto(s)
Antituberculosos/uso terapéutico , Infecciones por VIH/complicaciones , Isoniazida/uso terapéutico , Tuberculosis Pulmonar/prevención & control , Adulto , Antituberculosos/administración & dosificación , Esquema de Medicación , Humanos , Incidencia , Isoniazida/administración & dosificación , Malaui/epidemiología , Tuberculosis Pulmonar/epidemiología
12.
Malawi Med J ; 32(4): 184-191, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-34457202

RESUMEN

Introduction: Miners in sub-Saharan Africa have a greater risk of tuberculosis (TB) than any other working population in the world. In spite of the presence of large and vulnerable population of miners in Malawi, no previous study has aimed to assess the burden of TB among these miners. This study aimed to determine the prevalence of pulmonary tuberculosis (PTB) and health-seeking behaviour (HSB) in a population of miners in Malawi, and a range of associated factors. Our goal was to develop a method to identify missing cases of TB. Methods: We conducted a cross-sectional study in the Karonga, Rumphi, Kasungu and Lilongwe districts of Malawi in 2019. We calculated frequencies, proportions, odds ratios (ORs) and their 95% confidence intervals (95% CIs), and used the chi-square test in STATA version15.1 to investigate the burden and magnitude of PTB in the mining sector. Bivariate and multivariate logistic regression models were also fitted for PTB and HSB. Results: Of the 2400 miners approached, we were able to interview 2013 (84%). Of these, 1435 (71%) were males, 1438 (71%) had known HIV status and 272 (14%) had PTB. Multivariate analysis showed that the miners performing informal mining were 50% more likely to develop PTB compared with those in formal mining (adjusted odds ratio [AOR]=1.50, 95% CI: 1.10-2.05, P=0.01). A total of 459 (23% of 2013) miners had presumptive TB. Of these, 120 (26%) sought health care; 80% sought health care at health facilities. Multivariate analysis also showed that miners who experienced night sweats were less likely to seek health care compared with those without night sweats (AOR=0.52, 95% CI: 0.30-0.90, P=0.02). Conclusion: The prevalence of PTB was higher among miners than in the general population. Consequently, targeted TB screening programmes for miners may represent a suitable strategy to adopt if we are to end TB by 2030. Poor health-seeking behaviours among miners is worrisome and further qualitative research is necessary to understand the barriers to accessing health care in these settings.


Asunto(s)
Minería , Enfermedades Profesionales/epidemiología , Tuberculosis Pulmonar/epidemiología , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Malaui/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven
13.
Glob Health Action ; 12(1): 1672366, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31610754

RESUMEN

Background: Determine TB-LAM is a urine-based point-of-care assay for diagnosis of tuberculosis (TB). Objective: To assess the feasibility of using LAM to diagnose TB in adult HIV-positive patients in resource-limited settings. Methods: We performed a multi-centric mixed-methods cross-sectional descriptive study in the Democratic Republic of Congo, Malawi, and Mozambique. We used the study and program monitoring tools to estimate user workload, turn-around time (TAT), and proportion of patients with LAM and sputum-based results. We conducted semi-structured interviews to assess the user acceptability of the LAM. Results: The duration of the LAM testing activity per patient was 27 min (IQR 26-29); staff continued with other duties whilst waiting for the result. More patients had a LAM versus a sputum-based result: 168/213 (78.9%) vs 77/213 (36.1%), p < 0.001 in DRC; 691/695 (99.4%) vs 429/695 (61.7%), p < 0.001 in Malawi; and 646/647 (99.8%) vs 262/647 (40.5%), p < 0.001 in Mozambique. The median TAT in minutes when LAM was performed in the consultation room was 75 (IQR 45-188) in DRC, 29 (IQR 27-39) in Malawi, and 36 (IQR 35-41) in Mozambique. In comparison, the overall median TAT for sputum-based tests (smear or GeneXpert) was 2 (IQR 1-3) days. The median time to the first anti-TB drug dose for LAM-positive patients was 155 (IQR 90-504) minutes in DRC and 90 (IQR 60-117) minutes in Mozambique. The overall inter-reader agreement for the interpretation of the LAM result as positive or negative was 98.9%, kappa 0.97 (95%CI 0.96-0.99). Overall, LAM users found the test easy to perform. Major concerns were use of the reading card and the prior requirement of CD4 results before LAM testing. Conclusion: It is feasible to implement the LAM test in low resource settings. The short TAT permitted same day initiation of TB treatment for LAM-positive patients.


Asunto(s)
Infecciones por VIH/epidemiología , Tuberculosis/diagnóstico , Tuberculosis/epidemiología , África del Sur del Sahara/epidemiología , Estudios Transversales , Estudios de Factibilidad , Infecciones por VIH/tratamiento farmacológico , Humanos , Entrevistas como Asunto , Lipopolisacáridos , Sistemas de Atención de Punto , Sensibilidad y Especificidad , Esputo/microbiología
14.
J Int AIDS Soc ; 22(4): e25240, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-31038836

RESUMEN

INTRODUCTION: Although the use of antiretroviral therapy (ART) reduces HIV-associated tuberculosis (TB), patients living with HIV receiving ART remain at a higher risk of developing TB compared to those without HIV. We investigated the incidence of TB and the proportion of HIV-associated TB cases among patients living with HIV who are receiving ART. METHODS: The study used TB registration and ART programme data collected between 2008 and 2017 from an integrated, public clinic in urban Lilongwe, Malawi. ART initiation was based on either WHO clinical staging or CD4 cell count. The CD4 thresholds for ART initiation eligibility was initially 250 cells/µL then changed to 350 cells/µL in 2011, 500 cells/µL in 2014 and to universal treatment upon diagnosis from 2016. Using TB registration data, we calculated the proportion of TB/HIV patients who were already on ART when they registered for TB treatment by year of TB registration. ART registration data were used to examine TB incidence by calendar year of ART follow-up and by time on ART. RESULTS: The overall proportion of TB/patients living with HIV who started TB treatment while on ART increased from 21% in 2008 to 81% in 2017 but numbers remained relatively constant at 500 TB cases annually. The overall incidence rate of TB among patients on ART was 1.35/100 person-years (95% CI 1.28 to 1.42). The incidence of TB by time on ART decreased from 6.4/100 person-years in the first three months of ART to 0.4/100 person-years after eight years on ART. TB incidence was highest in the first month on ART. The annual rate of TB among patients on ART rapidly decreased each calendar year and stabilized at 1% after 2013. Although the risk of developing TB decreased with year of ART initiation in univariable analysis, there was no significant association after adjusting for sex, age and reason for ART eligibility. CONCLUSIONS: The decline in TB incidence over calendar years suggests protective effects of early ART initiation. The high TB incidence within the first month of ART highlights the need for more sensitive tools such as X-ray and GeneXpert to identify patients living with HIV who have clinical and subclinical TB disease at ART initiation.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Tuberculosis/etiología , Adulto , Instituciones de Atención Ambulatoria , Fármacos Anti-VIH/efectos adversos , Antituberculosos/uso terapéutico , Recuento de Linfocito CD4 , Estudios Transversales , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/inmunología , Humanos , Incidencia , Malaui/epidemiología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología
15.
J Multidiscip Healthc ; 11: 375-389, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30147328

RESUMEN

INTRODUCTION: The global burden of tuberculosis (TB) remains significantly high, with overreliance on biomedical interventions and inadequate exploration of the socioeconomic and cultural context of the infected population. A desired reduction in disease burden can be enhanced through a broader theoretical understanding of people's health beliefs and concerns about TB. In this qualitative study, we explore the knowledge, beliefs, and perceptions of community members and people diagnosed with TB toward TB in Ntcheu district, Malawi. METHODS: Using a qualitative phenomenological study design, data were obtained from eight focus-group discussions and 16 individual in-depth interviews. The community's experiences and perceptions of TB were captured without using any preconceived framework. Adult participants who had had or never had a diagnosis of TB were purposively selected by sex and age and enrolled for the study. Discussions and individual interviews lasting about 60 minutes each were audiotaped, transcribed, and translated into English and analyzed using MaxQDA 10 software for qualitative analysis. RESULTS: Most participants believed that TB was curable and would go for diagnosis if they had symptoms suggestive of the disease. However, based on their beliefs, individuals expressed some apprehension about the spread of TB and the social implications of being diagnosed with the disease. This perception affected participants' responses about seeking diagnosis and treatment. CONCLUSION: A supportive and collective approach consisting of a combination of mass media, interactive communication campaigns, emphasizing TB symptoms, transmission, and stigma could be useful in addressing barriers to early diagnosis and care-seeking behavior.

16.
Afr J Lab Med ; 6(2): 463, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28879159

RESUMEN

BACKGROUND: Availability and access to the detection of resistance to anti-tuberculosis drugs remains a significant challenge in Malawi due to limited diagnostic services. The Xpert® MTB/RIF can detect Mycobacterium tuberculosis and resistance to rifampicin in a single, rapid assay. Rifampicin-resistant M. tuberculosis has not been well studied in Malawi. OBJECTIVES: We aimed to determine mutations in the rifampicin resistance determining region (RRDR) of the rpoB gene of M. tuberculosis strains which were defined as resistant to rifampicin by the Xpert MTB/RIF assay. METHODS: Rifampicin-resistant isolates from 43 adult patients (≥ 18 years) from various districts of Malawi were characterised for mutations in the RRDR (codons 507-533) of the rpoB gene by DNA sequencing. RESULTS: Mutations were found in 37/43 (86%) of the resistant isolates in codons 511, 512, 513, 516, 522, 526 and 531. The most common mutations were in codons 526 (38%), 531 (29.7%) and 516 (16.2%). Mutations were not found in 6/43 (14%) of the resistant isolates. No novel rpoB mutations other than those previously described were found among the rifampicin-resistant M. tuberculosis complex strains. CONCLUSION: This study is the first to characterise rifampicin resistance in Malawi. The chain-termination DNA sequencing employed in this study is a standard method for the determination of nucleotide sequences and can be used to confirm rifampicin resistance obtained using other assays, including the Xpert MTB/RIF. Further molecular cluster analysis, such as spoligotyping and DNA finger printing, is still required to determine transmission dynamics and the epidemiological link of the mutated strains.

17.
Afr J Lab Med ; 6(2): 464, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28879160

RESUMEN

BACKGROUND: Xpert® MTB/RIF is a molecular test for the detection of Mycobacterium tuberculosis and rifampicin resistance. It is considered to be a great advance over smear microscopy and culture. However, there is very little information regarding the performance characteristics of Xpert MTB/RIF in Malawi. OBJECTIVE: We aimed to evaluate the performance of Xpert MTB/RIF in a Malawian setting. METHODS: Stored sputum pellets were processed on Xpert MTB/RIF between June 2012 and May 2014. Results were compared to mycobacteria growth indicator tube and Löwenstein-Jensen cultures, LED fluorescent microscopy and GenoType® MTBDRplus assay. Rifampicin resistance was confirmed by DNA sequencing. RESULTS: Of the 348 specimens with valid Xpert MTB/RIF results, 129/348 (37%) were smear-positive and 198/348 (57%) were culture-positive. Xpert MTB/RIF demonstrated a sensitivity of 93.8% (95% CI 89.4% - 96.8%) and specificity of 97.4% (95% CI 93.5% - 99.3%), with a positive predictive value of 97.8% (95% CI 94.6% - 99.4%) and a negative predictive value of 92.6% (95% CI 87.4% - 96.1%). Xpert MTB/RIF correctly identified 185/186 (99.5%) rifampicin-sensitive and 2/2 (100%) rifampicin-resistant M. tuberculosis strains. Mutations were not detected by sequencing in one isolate which was rifampicin resistant on Xpert MTB/RIF but sensitive on MTBDRplus. Four non-tuberculous mycobacteria grew from four smear-negative specimens, namely, M. avium (n = 1) and M. intracellulare (n = 3). No cross-reactivity was observed with any of the non-tuberculous mycobacteria when using Xpert MTB/RIF. CONCLUSION: When fully implemented, Xpert MTB/RIF may have an impact on patient care in Malawi. The increased diagnostic yield of Xpert MTB/RIF over smear microscopy can increase laboratory-confirmed tuberculosis detection and ensure that treatment is given to appropriate individuals or groups.

19.
Trop Med Int Health ; 21(1): 101-107, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26509352

RESUMEN

OBJECTIVES: Since 1985, Malawi has experienced a dual epidemic of HIV and tuberculosis (TB) which has been moderated recently by the advent of antiretroviral therapy (ART). The aim of this study was to describe the association over several decades between HIV/AIDS, the scale-up of ART and TB case notifications. METHODS: Aggregate data were extracted from annual reports of the National TB Control Programme, the Ministry of Health HIV Department and the National Statistics Office. ART coverage was calculated using the total HIV population as denominator (derived from UNAIDS Spectrum software). RESULTS: In 1970, there were no HIV-infected persons but numbers had increased to a maximum of 1.18 million by 2014. HIV prevalence reached a maximum of 10.8% in 2000, thereafter decreasing to 7.5% by 2014. Numbers alive on ART increased from 2586 in 2003 to 536 527 (coverage 45.3%) by 2014. In 1985, there were 5286 TB cases which reached a maximum of 28 234 in 2003 and then decreased to 17 723 by 2014 (37% decline from 2003). There were increases in all types of new TB between 1998-2003 which then declined by 30% for extrapulmonary TB, by 37% for new smear-positive PTB and by 50% for smear-negative PTB. Previously treated TB cases reached a maximum of 3443 in 2003 and then declined by 42% by 2014. CONCLUSION: The rise and fall of TB in Malawi between 1985 and 2014 was strongly associated with HIV infection and ART scale-up; this has implications for ending the TB epidemic in high HIV-TB burden countries.

20.
Trials ; 16: 576, 2015 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-26679768

RESUMEN

BACKGROUND: In developing countries like Malawi, further investigation is rare after patients with chronic cough test negative for tuberculosis. Chronic airways disease has presentations that overlap with tuberculosis. However, chronic airways disease is often unrecognised due to a lack of diagnostic services. Within developing countries, referral systems at primary health care level are weak and patients turn to unskilled informal health providers to seek health care. Delayed diagnosis and treatment of these diseases facilitates increased severity and tuberculosis transmission. The World Health Organisation developed the Practical Approach to Lung Health strategy which has been shown to improve the management of both tuberculosis and chronic airways disease. The guidelines address the need for integrated guidelines for tuberculosis and chronic airways disease. Engaging with informal health providers has been shown to be effective in improving health services uptake. However, it is not known whether engaging community informal health providers would have a positive impact in the implementation of the Practical Approach to Lung Health strategy. We will use a cluster randomised controlled trial to determine the effect of using the two interventions to improve case detection and treatment of patients with tuberculosis and chronic airways disease. METHODS: A three-arm cluster randomised trial design will be used. A primary health centre catchment population will form a cluster, which will be randomly allocated to one of the arms. The first arm personnel will receive the Practical Approach to Lung Health strategy intervention. In addition to this strategy, the second arm personnel will receive training of informal health providers. The third arm is the control. The effect of interventions will be evaluated by community surveys. Data regarding the diagnosis and management of chronic cough will be gathered from primary health centres. DISCUSSION: This trial seeks to determine the effect of Informal Health Provider and Practical Approach to Lung Health interventions on the detection and management of chronic airways disease and tuberculosis at primary care level in Malawi. TRIAL REGISTRATION: The unique identification number for the registry is PACTR201411000910192--21 November 2014.


Asunto(s)
Servicios de Salud Comunitaria , Tos/diagnóstico , Personal de Salud , Enfermedades Pulmonares/diagnóstico , Atención al Paciente , Atención Primaria de Salud , Tuberculosis Pulmonar/diagnóstico , Enfermedad Crónica , Servicios de Salud Comunitaria/normas , Tos/terapia , Vías Clínicas , Diagnóstico Tardío , Prestación Integrada de Atención de Salud , Países en Desarrollo , Personal de Salud/normas , Humanos , Enfermedades Pulmonares/terapia , Malaui , Atención al Paciente/normas , Guías de Práctica Clínica como Asunto , Valor Predictivo de las Pruebas , Atención Primaria de Salud/normas , Pronóstico , Mejoramiento de la Calidad , Proyectos de Investigación , Tuberculosis Pulmonar/terapia , Tuberculosis Pulmonar/transmisión , Recursos Humanos
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