Digital health solutions and integrated COVID-19 and TB services to help recover TB care and prevention services in the COVID-19 pandemic: A descriptive study in four high TB burden countries.

Background: The measures undertaken to control COVID-19 have disrupted many platforms including tuberculosis (TB) healthcare services. Consequently, declines in TB notifications have been observed in various countries. We visualized changes over time in TB and SARS-CoV-2 infection notifications and reported on country-specific strategies to retain TB care and prevention services in Kyrgyzstan, Nigeria, Tanzania, and Vietnam.

Newborn screening for sickle cell disease: an innovative pilot program to improve child survival in Dar es Salaam, Tanzania.

Background: Sickle cell disease (SCD) is a recognized cause of childhood mortality. Tanzania has the fifth highest incidence of SCD (with an estimated 11 000 SCD annual births) worldwide. Although newborn screening (NBS) for SCD and comprehensive healthcare have been shown to reduce under-5 mortality by up to 94% in high-income countries such as the USA, no country in Africa has maintained NBS for SCD as a national health program.

Increased mortality associated with treated active tuberculosis in HIV-infected adults in Tanzania.

Active tuberculosis (TB) among HIV-infected patients, even when successfully treated, may be associated with excess mortality. We conducted a prospective cohort study nested in a randomized TB vaccine trial to compare mortality between HIV-infected patients diagnosed and treated for TB (TB, n = 77) and HIV-infected patients within the same CD4 range, who were not diagnosed with or treated for active TB (non-TB, n = 308) in the period 2001-2008. Only twenty four subjects (6%) were on antiretroviral therapy at the beginning of this study.

Recurrent tuberculosis risk among HIV-infected adults in Tanzania with prior active tuberculosis.

Background: Active tuberculosis is common among human immunodeficiency virus (HIV)-infected persons living in tuberculosis-endemic areas, but the hazard of subsequent tuberculosis disease has not been quantified in a single prospective cohort.

Methods: Among HIV-infected, BCG-immunized adults with CD4 counts ≥200 cells/μL who received placebo in the DarDar tuberculosis vaccine trial in Tanzania, we compared the prospective risk of active tuberculosis between subjects who did and who did not report prior active tuberculosis. All subjects with a positive tuberculin skin test without prior active tuberculosis were offered isoniazid preventive treatment.

Molecular epidemiology of HIV-associated tuberculosis in Dar es Salaam, Tanzania: strain predominance, clustering, and polyclonal disease.

Molecular typing of Mycobacterium tuberculosis can be used to elucidate the epidemiology of tuberculosis, including the rates of clustering, the frequency of polyclonal disease, and the distribution of genotypic families. We performed IS6110 typing and spoligotyping on M. tuberculosis strains isolated from HIV-infected subjects at baseline or during follow-up in the DarDar Trial in Tanzania and on selected community isolates.

Maintenance of Sensitivity of the T-SPOT.TB Assay after Overnight Storage of Blood Samples, Dar es Salaam, Tanzania.

Background. T-SPOT.TB is an interferon gamma release assay for detecting Mycobacterium tuberculosis infection.

Completion of isoniazid preventive therapy and survival in HIV-infected, TST-positive adults in Tanzania.

Setting: The World Health Organization recommends the use of isoniazid preventive therapy (IPT) for human immunodeficiency virus (HIV) infected patients with a positive tuberculin skin test (TST). However, due to concerns about the effectiveness of IPT in community health care settings and the development of drug resistance, these recommendations have not been widely implemented in countries where tuberculosis (TB) and HIV co-infection is common.

Objective: To evaluate the effectiveness of IPT on survival and TB incidence among HIV-infected patients in Tanzania.

Polyantigenic interferon-γ responses are associated with protection from TB among HIV-infected adults with childhood BCG immunization.

Background: Surrogate immunologic markers for natural and vaccine-mediated protection against tuberculosis (TB) have not been identified.

Methods: HIV-infected adults with childhood BCG immunization entering the placebo arm of the DarDar TB vaccine trial in Dar es Salaam, Tanzania, were assessed for interferon gamma (IFN-γ) responses to three mycobacterial antigen preparations--secreted Mycobacterium tuberculosis antigens 85 (Ag85), early secretory antigenic target 6 (ESAT-6) and polyantigenic whole cell lysate (WCL). We investigated the association between the number of detectable IFN-γ responses at baseline and the subsequent risk of HIV-associated TB.

Disseminated tuberculosis in human immunodeficiency virus infection: ineffective immunity, polyclonal disease and high mortality.

Background: Disseminated tuberculosis (TB) is a major cause of death in patients with the acquired immune-deficiency syndrome (AIDS), but its pathogenesis and clinical features have not been defined prospectively.

Methods: Human immunodeficiency virus (HIV) infected adults with a CD4 count ≥ 200 cells/μl and bacille Calmette-Guérin scar underwent immunologic evaluation and subsequent follow-up.

Results: Among 20 subjects who developed disseminated TB, baseline tuberculin skin tests were ≥15 mm in 14 (70%) and lymphocyte proliferative responses to Mycobacterium tuberculosis were positive in 14 (70%).

Low BMI and falling BMI predict HIV-associated tuberculosis: a prospective study in Tanzania.

Background: Low body mass index (BMI) is a known risk factor for tuberculosis (TB) in people without human immunodeficiency virus (HIV), but there are no prospective studies linking BMI to the risk of HIV-associated TB.

Design: In HIV-infected adults with CD4 counts ≥ 200 cells/μl receiving placebo in a TB booster vaccine trial in Dar es Salaam, Tanzania, we measured BMI at baseline and Year 1, and related baseline BMI and change in BMI to the risk of developing TB.

Results: We documented 92 cases of TB among 979 subjects followed for a mean of 3.

Immunogenicity of a protective whole cell mycobacterial vaccine in HIV-infected adults: a phase III study in Tanzania.

Preventive immunization with whole inactivated Mycobacterium vaccae (MV) confers protection against HIV-associated tuberculosis (TB) in BCG-immunized adults with CD4 counts ≥200 cells/μl. We evaluated the immunogenicity of MV in the 2013 subjects of the phase III DarDarTrial using an interferon gamma (IFN-γ) enzyme linked immunosorbent assay (ELISA), tritiated thymidine lymphocyte proliferation assay (LPA) and an ELISA for antibodies to the TB glycolipid lipoarabinomannan (LAM). MV immunization boosts IFN-γ and LPA responses to MV sonicate, and antibody responses to LAM.

Interferon γ responses to mycobacterial antigens protect against subsequent HIV-associated tuberculosis.

Background: The cellular immune responses that protect against tuberculosis have not been identified.

Methods: We assessed baseline interferon γ (IFN‐γ) and lymphocyte proliferation assay (LPA) responses to antigen 85 (Ag85), early secretory antigenic target 6 (ESAT‐6), and Mycobacterium tuberculosis whole cell lysate (WCL) in human immunodeficiency virus (HIV)-infected and bacille Calmette‐Guérin (BCG)-immunized adults with CD4 cell counts of >or= 200 cells/μL who received placebo in the DarDar tuberculosis vaccine trial in Tanzania. Subjects were followed prospectively to diagnose definite or probable tuberculosis.

Prevention of tuberculosis in Bacille Calmette-Guérin-primed, HIV-infected adults boosted with an inactivated whole-cell mycobacterial vaccine.

Objective: To determine whether a multiple-dose series of an inactivated whole cell mycobacterial vaccine, Mycobacterium vaccae, can prevent HIV-associated tuberculosis.

Design And Methods: The DarDar trial was a randomized, placebo-controlled, double-blind trial. The study was carried in an outpatient facility in Dar es Salaam, Tanzania.

Lymphocyte proliferation to mycobacterial antigens is detectable across a spectrum of HIV-associated tuberculosis.

Background: Identifying novel TB diagnostics is a major public health priority. We explored the diagnostic characteristics of antimycobacterial lymphocyte proliferation assays (LPA) in HIV-infected subjects with latent or active TB.

Methods: HIV-infected subjects with bacille Calmette Guérin (BCG) scars and CD4 counts > or = 200 cells/mm(3) entering a TB booster vaccine trial in Tanzania had baseline in vivo and in vitro immune tests performed: tuberculin skin tests (TST), LPA and five day assays of interferon gamma (IFN-gamma) release.

Completion of isoniazid preventive therapy among HIV-infected patients in Tanzania.

Setting: Isoniazid preventive therapy (IPT) has not been widely implemented due to questions about acceptance, adherence and side effects.

Objective: To examine factors related to completion of IPT among human immunodeficiency virus (HIV) infected subjects in Tanzania.

Design: HIV-infected subjects in the DarDar TB vaccine trial with CD4 cell counts >or=200 cells/mm(3) and a positive tuberculin skin test (TST) were counseled, offered IPT for 6 months and seen monthly.

Basis for treatment of tuberculosis among HIV-infected patients in Tanzania: the role of chest x-ray and sputum culture.

Background: Active tuberculosis (TB) is common among HIV-infected persons living in tuberculosis endemic countries, and screening for tuberculosis (TB) is recommended routinely. We sought to determine the role of chest x-ray and sputum culture in the decision to treat for presumptive TB using active case finding in a large cohort of HIV-infected patients.

Methods: Ambulatory HIV-positive subjects with CD4 counts > or = 200/mm3 entering a Phase III TB vaccine study in Tanzania were screened for TB with a physical examination, standard interview, CD4 count, chest x-ray (CXR), blood culture for TB, and three sputum samples for acid fast bacillus (AFB) smear and culture.

Sputum microscopy for the diagnosis of HIV-associated pulmonary tuberculosis in Tanzania.

Background: In many resource poor settings only sputum microscopy is employed for the diagnosis of HIV-associated pulmonary tuberculosis; sputum culture may not be available.

Methods: We determined the diagnostic accuracy of sputum microscopy for active case finding of HIV-associated pulmonary tuberculosis using TB culture as the reference standard.

Results: 2216 potential subjects screened for a TB vaccine trial submitted 9454 expectorated sputum specimens: 212 (2.

Baseline mycobacterial immune responses in HIV-infected adults primed with bacille Calmette-Guérin during childhood and entering a tuberculosis booster vaccine trial.

Background: Most new tuberculosis vaccines will be administered as a booster to subjects primed with bacille Calmette-Guérin (BCG) during childhood.

Methods: We investigated in vivo and in vitro immune responses to mycobacteria in human immunodeficiency virus (HIV)-positive subjects in Tanzania primed with BCG during childhood and entering a tuberculosis booster vaccine trial. Tests included intradermal skin testing for Mycobacterium tuberculosis purified protein derivative (PPD) and Mycobacterium avium sensitin (MAS); lymphocyte proliferation assays and interferon (IFN)-gamma levels after stimulation with Mycobacterium vaccae sonicate (MVS), M.

High rates of clinical and subclinical tuberculosis among HIV-infected ambulatory subjects in Tanzania.

Background: We sought to determine the prevalence of active tuberculosis among ambulatory HIV-infected persons in Tanzania with CD4 cell counts of > or =200 cells/mm3 and a bacille Calmette-Guerin vaccination scar.

Methods: Subjects who volunteered for a tuberculosis booster vaccine trial were screened for active tuberculosis by obtainment of a history, physical examination, chest radiography, sputum culture and acid fast bacillus (AFB) stain, and blood culture. All subjects underwent a tuberculin skin test (TST) and lymphocyte proliferation assays (LPAs) for detection of responses to mycobacterial antigens.

HIV infection in elderly medical patients.

Objective: To determine the prevalence and presentation of HIV-infection among medical admissions aged 55 years and above.

Design: Prospective cross-sectional study.

Setting: Dar es Salaam, Tanzania.