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INTRODUCTION: When COVID-19 hit the world in 2019, an enhanced focus on diagnostic testing for SARS-CoV-2 was essential for a successful pandemic response. Testing laboratories stretched their capabilities for the new coronavirus by adopting different test methods. The necessity of having external quality assurance (EQA) mechanisms was even more critical due to this rapid expansion. However, there was a lack of experience in providing the necessary SARS-CoV-2 EQA materials, especially in locations with constrained resources. OBJECTIVE: We aimed to create a PT (Proficiency testing) programme based on the Dried Tube Specimens (DTS) method that would be a practical option for molecular based SARS-CoV-2 EQA in Low- and Middle-Income Countries. METHODS: Based on previous ISO/IEC 17043:2010 accreditation experiences and with assistance from the US Centers for Disease Control and Prevention, The Supranational Reference Laboratory of Uganda (adapted the DTS sample preparation method and completed a pilot EQA program between 2020 and 2021. Stability and panel validation testing was conducted on the designed materials before shipping to pilot participants in six African countries. Participants received a panel containing five SARS-CoV-2 DTS samples, transported at ambient conditions. Results submitted by participants were compared to validation results. Participants were graded as satisfactory (≥ 80%) or unsatisfactory (< 80%) and performance reports disseminated. RESULTS: Our SARS-CoV-2 stability experiments showed that SARS-CoV-2 RNA was stable (-15 to -25 °C, 4 to 8 °C, (18 to 28 °C) room temperature and 35 to 38 °C) as well as DTS panels (4 to 8 °C, 18 to 28 °C, 35 to 38 °C and 45 °C) for a period of 4 weeks. The SARS-CoV-2 DTS panels were successfully piloted in 35 test sites from Zambia, Malawi, Mozambique, Nigeria, and Seychelles. The pilot results of the participants showed good accuracy, with an average of 86% (30/35) concordance with the original SARS CoV-2 expectations. CONCLUSION: The SARS-CoV-2 DTS PT panel is reliable, stable at ambient temperature, simple to prepare and requires minimal resources.
Subject(s)
COVID-19 , Developing Countries , Laboratory Proficiency Testing , SARS-CoV-2 , Specimen Handling , Humans , COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Specimen Handling/methods , Specimen Handling/standards , COVID-19 Testing/methods , Uganda , Pilot ProjectsABSTRACT
Mycobacterium tuberculosis remains one of the deadliest infectious agents globally. Amidst efforts to control TB, long treatment duration, drug toxicity, and resistance underscore the need for novel therapeutic strategies. Despite advances in understanding the interplay between microbiome and disease in humans, the specific role of the microbiome in predicting disease susceptibility and discriminating infection status in tuberculosis still needs to be fully investigated. We investigated the impact of M.tb infection and M.tb-specific IFNγ immune responses on airway microbiome diversity by performing TB GeneXpert and QuantiFERON-GOLD assays during the follow-up phase of a longitudinal HIV-Lung Microbiome cohort of individuals recruited from two large independent cohorts in rural Uganda. M.tb rather than IFNγ immune response mainly drove a significant reduction in airway microbiome diversity. A microbiome signature comprising Streptococcus, Neisseria, Fusobacterium, Prevotella, Schaalia, Actinomyces, Cutibacterium, Brevibacillus, Microbacterium, and Beijerinckiacea accurately discriminated active TB from Latent TB and M.tb-uninfected individuals.
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Mother-to-child transmission (MTCT) of HIV-1 and associated mortality continue to occur at unacceptably high rates, despite the extensive rollout and implementation of Prevention of Mother-to-Child Transmission (PMTCT) Programs, including the modified versions of Option B and B+ in 2010 and 2012, respectively. Maternal HIV viral load (VL) and socio-behavioral factors sustaining MTCT in Rwanda remain largely unexplored. The study examined the effects of socio-behavioral factors on maternal VL and their contribution to in utero transmission of HIV-1 in the context of Rwanda's HIV epidemic. A prospective cohort study was conducted in 862 mother-baby pairs enrolled in 10 PMTCT clinics in Rwanda. VL was determined on plasma and Dried Blood Spots samples, whereas HIV DNA PCR was performed to determine in utero MTCT of HIV of the babies immediately at birth and then at 3 weeks, 4 weeks, 6 months, and 18 months, together with HIV antibody testing to determine other forms of MTCT of HIV. Quantitative data on socio-behavioral factors were collected through a structured questionnaire. Linear regression and univariate analysis of variances using SPSS 25.0 were used to test the hypotheses. We found 22/862 (2.55%) cases of in utero transmission and a total of 32/862 (3.7%) cases of MTCT of HIV-1 over 18 study months. Maternal VL at delivery was significantly associated with the risk of in utero transmission of HIV-1. Socio-behavioral factors associated with elevated maternal VL at delivery included alcohol, smoking, multiple sexual partners, mothers' income, being a casual laborer, and distance to health care services. We report an MTCT rate of 3.7% in our study population over the 18 months, higher than the national average of 1.5%, the majority of which occurred in utero. MTCT cases were attributable to failure to suppress maternal VL.
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BACKGROUND: Significant milestones have been made in the development of COVID19 diagnostics Technologies. Government of the republic of Uganda and the line Ministry of Health mandated Uganda Virus Research Institute to ensure quality of COVID19 diagnostics. Re-testing was one of the methods initiated by the UVRI to implement External Quality assessment of COVID19 molecular diagnostics. METHOD: participating laboratories were required by UVRI to submit their already tested and archived nasopharyngeal samples and corresponding meta data. These were then re-tested at UVRI using the WHO Berlin protocol, the UVRI results were compared to those of the primary testing laboratories in order to ascertain performance agreement for the qualitative & quantitative results obtained. Ms Excel window 12 and GraphPad prism ver 15 was used in the analysis. Bar graphs, pie charts and line graphs were used to compare performance agreement between the reference Laboratory and primary testing Laboratories. RESULTS: Eleven (11) Ministry of Health/Uganda Virus Research Institute COVID19 accredited laboratories participated in the re-testing of quality control samples. 5/11 (45%) of the primary testing laboratories had 100% performance agreement with that of the National Reference Laboratory for the final test result. Even where there was concordance in the final test outcome (negative or positive) between UVRI and primary testing laboratories, there were still differences in CT values. The differences in the Cycle Threshold (CT) values were insignificant except for Tenna & Pharma Laboratory and the UVRI(p = 0.0296). The difference in the CT values were not skewed to either the National reference Laboratory(UVRI) or the primary testing laboratory but varied from one laboratory to another. In the remaining 6/11 (55%) laboratories where there were discrepancies in the aggregate test results, only samples initially tested and reported as positive by the primary laboratories were tested and found to be false positives by the UVRI COVID19 National Reference Laboratory. CONCLUSION: False positives were detected from public, private not for profit and private testing laboratories in almost equal proportion. There is need for standardization of molecular testing platforms in Uganda. There is also urgent need to improve on the Laboratory quality management systems of the molecular testing laboratories in order to minimize such discrepancies.
Subject(s)
COVID-19 , Humans , COVID-19/diagnosis , Uganda , Real-Time Polymerase Chain Reaction , COVID-19 Testing , Academies and InstitutesABSTRACT
Childhood HBV immunization remains globally fundamental to the elimination of hepatitis B virus (HBV). However, monitoring proportions of HBV vaccine seroprotection and their determinants among African Pediatric recipients is crucial. This study sought to verify extent of immune protection accorded by the HBV vaccine in African children of up to 17 years of age by pooling the prevalence of seroprotection reported by primary studies conducted in the Northern, Western, and Southern African regions. We included 19 eligible articles out of the 197 initially downloaded, published from 1999 to 2021 from African Journals Online (AJOL), EMBASE, Scopus, and PubMed. The study protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO), University of York Centre for Reviews and Dissemination, under the registration number CRD42022361277. Significantly higher (p < 0.0001) proportion of HBV vaccine seroprotection (69.07%) was found among children under 15 years of age than children 15-17 years (32.368%), 95% CI [34.2454-39.0847%]. Whereas successful integration of the HBV vaccine on the extended programs on immunizations (EPI) has been a major achievement in the reduction of HBV infection in Africa, markedly reduced HBV vaccine seroprotection is persistently demonstrated among adolescent children 15-17 years of age. Future studies are required to clarify the need for booster dose vaccination in most at risk populations and age groups.
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Hepatitis B Vaccines , Hepatitis B , Adolescent , Child , Humans , Hepatitis B/epidemiology , Hepatitis B/prevention & control , Hepatitis B Antibodies , Hepatitis B Surface Antigens , Hepatitis B virusABSTRACT
Introduction: Survival among people with HIV-associated cryptococcal meningitis (CM) remains low, particularly among women, despite the currently optimal use of antifungal drugs. Cryptococcus dissemination into the central nervous system [brain, spinal cord, and cerebrospinal fluid (CSF)] elicits the local production of cytokines, chemokines, and other biomarkers. However, no consistent diagnostic or prognostic neuroimmune signature is reported to underpin the risk of death or to identify mechanisms to improve treatment and survival. We hypothesized that distinct neuroimmune signatures in the CSF would distinguish survivors from people who died on antifungal treatment and who may benefit from tailored therapy. Methods: We considered baseline clinical features, CSF cryptococcal fungal burden, and CSF neuroimmune signatures with survival at 18 weeks among 419 consenting adults by "gender" (168 women and 251 men by biological sex defined at birth). Results: Survival at 18 weeks was significantly lower among women than among men {47% vs. 59%, respectively; hazard ratio (HR) = 1.4 [95% confidence interval (CI), 1.0 to 1.9; p = 0.023]}. Unsupervised principal component analysis (PCA) demonstrated divergent neuroimmune signatures by gender, survival, and intragender-specific survival. Overall, women had lower levels of programmed death ligand 1, Interleukin (IL) (IL-11RA/IL-1F30, and IL-15 (IL-15) than men (all p < 0.028). Female survivors compared with those who died expressed significant elevations in levels of CCL11 and CXCL10 chemokines (both p = 0.001), as well as increased T helper 1, regulatory, and T helper 17 cytokines (all p < 0.041). In contrast, male survivors expressed lower levels of IL-15 and IL-8 compared with men who died (p < 0.044). Conclusions: Survivors of both genders demonstrated a significant increase in the levels of immune regulatory IL-10. In conclusion, the lower survival among women with CM was accompanied by distinct differential gender-specific neuroimmune signatures. These female and male intragender-specific survival-associated neuroimmune signatures provide potential targets for interventions to advance therapy to improve the low survival among people with HIV-associated CM.
Subject(s)
HIV Infections , Meningitis, Cryptococcal , Adult , Infant, Newborn , Humans , Female , Male , Meningitis, Cryptococcal/drug therapy , Interleukin-15/therapeutic use , Antifungal Agents/therapeutic use , Cytokines/therapeutic use , Chemokines/therapeutic use , Interleukins/therapeutic use , HIV Infections/drug therapy , HIV Infections/complicationsABSTRACT
Despite recent efforts to increase diversity in genome-wide association studies (GWASs), most loci currently associated with kidney function are still limited to European ancestry due to the underlying sample selection bias in available GWASs. We set out to identify susceptibility loci associated with estimated glomerular filtration rate (eGFRcrea) in 80027 individuals of African-ancestry from the UK Biobank (UKBB), Million Veteran Program (MVP), and Chronic Kidney Disease genetics (CKDGen) consortia.We identified 8 lead SNPs, 7 of which were previously associated with eGFR in other populations. We identified one novel variant, rs77408001 which is an intronic variant mapped to the ELN gene. We validated three previously reported loci at GATM-SPATA5L1, SLC15A5 and AGPAT3. Fine-mapping analysis identified variants rs77121243 and rs201602445 as having a 99.9% posterior probability of being causal. Our results warrant designing bigger studies within individuals of African ancestry to gain new insights into the pathogenesis of Chronic Kidney Disease (CKD), and identify genomic variants unique to this ancestry that may influence renal function and disease.
Subject(s)
Genome-Wide Association Study , Renal Insufficiency, Chronic , Humans , Black People/genetics , Mutation , Renal Insufficiency, Chronic/genetics , KidneyABSTRACT
The estimated mortality rate of the SARS-CoV-2 pandemic varied greatly around the world. In particular, multiple countries in East, Central, and West Africa had significantly lower rates of COVID-19 related fatalities than many resource-rich nations with significantly earlier wide-spread access to life-saving vaccines. One possible reason for this lower mortality could be the presence of pre-existing cross-reactive immunological responses in these areas of the world. To explore this hypothesis, an exploratory study of stored peripheral blood mononuclear cells (PBMC) from Ugandans collected from 2015-2017 prior to the COVID-19 pandemic (n = 29) and from hospitalized Ugandan COVID-19 patients (n = 3) were examined using flow-cytometry for the presence of pre-existing SARS-CoV-2 cross-reactive CD4+ and CD8+ T-cell populations using four T-cell epitope mega pools. Of pre-pandemic participants, 89.7% (26/29) had either CD4+ or CD8+, or both, SARS-CoV-2 specific T-cell responses. Specifically, CD4+ T-cell reactivity (72.4%) and CD8+ T-cell reactivity (65.5%) were relatively similar, and 13 participants (44.8%) had both types of cross-reactive types of T-cells present. There were no significant differences in response by sex in the population, however this may be in part due to the limited sample size examined. The rates of cross-reactive T-cell populations in this exploratory Ugandan population appears higher than previous estimates from resource-rich countries like the United States (20-50% reactivity). It is unclear what role, if any, this cross-reactivity played in decreasing COVID-19 related mortality in Uganda and other African countries, but does suggest that a better understanding of global pre-existing immunological cross-reactivity could be an informative data of epidemiological intelligence moving forward.
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BACKGROUND: Neonatal mortality due to tetanus persists in Uganda despite the mandatory vaccination of pregnant mothers. Maternal antibodies wane within a year. Uganda's maternal vaccination guidelines do not specify the timing or frequency of tetanus shots, contributing to suboptimal transfer of tetanus antibodies to neonates. We aimed to determine the prevalence and factors associated with protective tetanus antibodies among newborns at Kawempe National Referral Hospital. METHODS: We conducted a cross-sectional study among 293 mother-newborn pairs. At delivery, neonatal cord and maternal venous blood were collected and titred for antitetanus antibodies using a quantitative ELISA kit. The primary outcome of the study was the proportion of newborn babies with tetanus antibodies ≥0.1 IU/mL. Associated factors were determined using generalised linear models for the Poisson family with a log link and robust variance estimation. RESULTS: A total of 258/293 (88.1%) newborns had protective antibody titres. Factors associated with adequate protective antibodies in the newborn included: high (≥0.1 IU/mL) maternal antibody titres, first antenatal visit ≥12 weeks of gestation and receiving a tetanus toxoid (TT) shot ≥28 weeks of gestation. However, number of doses received before current pregnancy was not associated with adequate protective antibody titres. CONCLUSION: There is a high prevalence of adequate protective levels of antibodies among TT-vaccinated mothers. Maternal titres and a third trimester TT dose correlate with adequate levels of protective anti-TT antibodies among newborns. A third trimester TT dose is recommended.
Subject(s)
Mothers , Tetanus , Pregnancy , Infant , Infant, Newborn , Humans , Female , Tetanus/prevention & control , Tetanus Toxoid , Toxoids , Uganda/epidemiology , Cross-Sectional StudiesABSTRACT
Survival among people with HIV-associated cryptococcal meningitis (CM) remains low, exceptionally among women with the increased threat of death on current optimal use of antifungal drugs. Cryptococcus dissemination into the central nervous system (CNS) prompts a neuroimmune reaction to activate pathogen concomitant factors. However, no consistent diagnostic or prognostic immune-mediated signature is reported to underpin the risk of death or mechanism to improve treatment or survival. We theorized that the distinct neuroimmune cytokine or chemokine signatures in the cerebrospinal fluid (CSF), distinguish survivors from people who died on antifungal treatment, who may benefit from tailored therapy. We considered the baseline clinical disease features, cryptococcal microbiologic factors, and CSF neuroimmune modulated signatures among 419 consenting adults by gender (biological sex assigned at birth) (168 females and 251 males) by 18 weeks of survival on antifungal management. Survival at 18 weeks was inferior among females than males (47% vs. 59%; hazard ratio HR=1.4, 95% CI: 1.0 to 1.9, and p=0.023). Unsupervised principal component analysis (PCA) demonstrated the divergent neuroimmune signatures by gender, survival, and intragender-specific survival. Overall, females displayed lower levels of PD-L1, IL-1RA, and IL-15 than males (all p≤0.028). Female survivors compared with those who died, expressed significant fold elevations in levels of CSF (CCL11 - myeloid and CXCL10 - lymphoid chemokine (in both p=0.001), and CSF Th1, Th2, and Th17 cytokines. In contrast, male survivors expressed distinctly lower levels of CSF IL-15 and IL-8 compared with those who died. Survivors of either gender demonstrated a significant increase in the levels of immune regulatory element, IL-10. In the finale, we classified divergent neuroimmune key signatures in CSF by gender, survival, and intragender-specific survival among people with HIV-associated cryptococcal meningitis. These intragender-specific survival associated-neuroimmune signatures, suggests the discrete role of gender immune regulating mechanisms as the possible targets for interventions to advance therapy to improve survival among people with HIV-associated cryptococcal meningitis.
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Schistosomiasis is a disease caused by parasitic flatworms of the Schistosoma spp., and is increasingly recognized to alter the immune system, and the potential to respond to vaccines. The impact of endemic infections on protective immunity is critical to inform vaccination strategies globally. We assessed the influence of Schistosoma mansoni worm burden on multiple host vaccine-related immune parameters in a Ugandan fishing cohort (n = 75) given three doses of a Hepatitis B (HepB) vaccine at baseline and multiple timepoints post-vaccination. We observed distinct differences in immune responses in instances of higher worm burden, compared to low worm burden or non-infected. Concentrations of pre-vaccination serum schistosome-specific circulating anodic antigen (CAA), linked to worm burden, showed a significant bimodal distribution associated with HepB titers, which was lower in individuals with higher CAA values at month 7 post-vaccination (M7). Comparative chemokine/cytokine responses revealed significant upregulation of CCL19, CXCL9 and CCL17 known to be involved in T cell activation and recruitment, in higher CAA individuals, and CCL17 correlated negatively with HepB titers at month 12 post-vaccination. We show that HepB-specific CD4+ T cell memory responses correlated positively with HepB titers at M7. We further established that those participants with high CAA had significantly lower frequencies of circulating T follicular helper (cTfh) subpopulations pre- and post-vaccination, but higher regulatory T cells (Tregs) post-vaccination, suggesting changes in the immune microenvironment in high CAA could favor Treg recruitment and activation. Additionally, we found that changes in the levels of innate-related cytokines/chemokines CXCL10, IL-1ß, and CCL26, involved in driving T helper responses, were associated with increasing CAA concentration. This study provides further insight on pre-vaccination host responses to Schistosoma worm burden which will support our understanding of vaccine responses altered by pathogenic host immune mechanisms and memory function and explain abrogated vaccine responses in communities with endemic infections.
Subject(s)
Schistosomiasis mansoni , Animals , Schistosomiasis mansoni/epidemiology , Antigens, Helminth , Schistosoma mansoni , Cytokines , Vaccination , ImmunityABSTRACT
INTRODUCTION: The long duration of tuberculosis treatment, as well as the 2-year post-treatment follow-up period often required for predicting relapse, present a hindrance to drug development and treatment monitoring efforts. Therefore, there is need for treatment response biomarkers to inform treatment time shortening, clinical decision-making, and inform clinical trials. OBJECTIVES: To assess the abilities of serum host biomarkers to predict treatment response among active PTB patients. METHODS: Active pulmonary TB patients (n = 53) as confirmed by sputum MGIT culture were enrolled at a TB treatment centre in Kampala, Uganda. We evaluated concentrations of 27 serum host biomarkers at baseline, month 2, and month 6 following the initiation of anti-tuberculosis treatment using the luminex platform for their ability to predict sputum culture status at month-2 post treatment initiation. RESULTS: There were significant differences in concentrations of IL1ra, IL1ß, IL6, IP10, MCP-1, and IFNγ during treatment. A bio-signature comprising TTP, TNFα, PDGF-BB, IL9, and GCSF best predicted month 2 culture conversion with sensitivity and specificity of 82% (95% CI; 66 -92% and 57 -96% respectively). Slow anti-TB treatment responders had higher pro-inflammatory marker levels during treatment. The strongest correlation was observed between VEGF and IL12p70 (0.94), IL17A and basic FGF (0.92), basic FGF, and IL2 (0.88), and IL10 with IL17A (0.87). CONCLUSION: We identified host biomarkers that predicted early response to PTB treatment, which may be valuable in future clinical trials and treatment monitoring. Similarly, strong correlations between biomarkers provide options for biomarkers substitutions during the development of treatment response monitoring tools or point of care tests.
Subject(s)
Mycobacterium tuberculosis , Tuberculosis , Humans , Antitubercular Agents/therapeutic use , Treatment Outcome , Uganda , BiomarkersABSTRACT
Antimicrobial resistance (AMR) in Neisseria gonorrhoeae (NG), compromising gonorrhea treatment, is a global public health concern. Improved, quality-assured NG AMR monitoring at the global level is essential. This mini-review examined NG AMR susceptibility surveillance and AMR data from the African continent from 2001 to 2020. Eligible peer-reviewed publications (n = 30) containing NG AMR data for antimicrobials currently recommended for gonorrhea treatment were included. Overall, very limited NG surveillance and AMR data was available. Furthermore, the NG AMR surveillance studies varied greatly regarding surveillance protocols (e.g., populations and samples tested, sample size, antimicrobials examined), methodologies (e.g., antimicrobial susceptibility testing method [agar dilution, minimum inhibitory concentration (MIC) gradient strip test, disc diffusion test] and interpretative criteria), and quality assurance (internal quality controls, external quality assessments [EQA], and verification of AMR detected). Moreover, most studies examined a suboptimal number of NG isolates, i.e., less than the WHO Global Gonococcal Antimicrobial Surveillance Program (GASP) and WHO Enhanced GASP (EGASP) recommendations of ≥100 isolates per setting and year. The notable inter-study variability and frequently small sample sizes make appropriate inter-study and inter-country comparisons of AMR data difficult. In conclusion, it is imperative to establish an enhanced, standardized and quality-assured NG AMR surveillance, ideally including patient metadata and genome sequencing as in WHO EGASP, in Africa, the region with the highest gonorrhea incidence globally. This will enable the monitoring of AMR trends, detection of emerging AMR, and timely refinements of national and international gonorrhea treatment guidelines. To achieve this aim, national and international leadership, political and financial commitments are imperative.
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The impact of endemic infections on protective immunity is critical to inform vaccination strategies. In this study, we assessed the influence of Schistosoma mansoni infection on host responses in a Ugandan fishing cohort given a Hepatitis B (HepB) vaccine. Concentrations of schistosome-specific circulating anodic antigen (CAA) pre-vaccination showed a significant bimodal distribution associated with HepB titers, which were lower in individuals with high CAA. We established that participants with high CAA had significantly lower frequencies of circulating T follicular helper (cTfh) subpopulations pre- and post-vaccination and higher regulatory T cells (Tregs) post-vaccination. Polarization towards higher frequencies of Tregs: cTfh cells can be mediated by changes in the cytokine environment favoring Treg differentiation. In fact, we observed higher levels of CCL17 and soluble IL-2R pre-vaccination (important for Treg recruitment and development), in individuals with high CAA that negatively associated with HepB titers. Additionally, alterations in pre-vaccination monocyte function correlated with HepB titers, and changes in innate-related cytokines/chemokine production were associated with increasing CAA concentration. We report, that by influencing the immune landscape, schistosomiasis has the potential to modulate immune responses to HepB vaccination. These findings highlight multiple Schistosoma -related immune associations that could explain abrogated vaccine responses in communities with endemic infections. Author Summary: Schistosomiasis drives host immune responses for optimal pathogen survival, potentially altering host responses to vaccine-related antigen. Chronic schistosomiasis and co-infection with hepatotropic viruses are common in countries where schistosomiasis is endemic. We explored the impact of Schistosoma mansoni ( S. mansoni ) infection on Hepatitis B (HepB) vaccination of individuals from a fishing community in Uganda. We demonstrate that high schistosome-specific antigen (circulating anodic antigen, CAA) concentration pre-vaccination, is associated with lower HepB antibody titers post-vaccination. We show higher pre-vaccination levels of cellular and soluble factors in instances of high CAA that are negatively associated with HepB antibody titers post-vaccination, which coincided with lower frequencies of circulating T follicular helper cell populations (cTfh), proliferating antibody secreting cells (ASCs), and higher frequencies of regulatory T cells (Tregs). We also show that monocyte function is important in HepB vaccine responses, and that high CAA is associated with alterations in the early innate cytokine/chemokine microenvironment. Our findings suggest that in individuals with high CAA and likely high worm burden, schistosomiasis creates and sustains an environment that is polarized against optimal host immune responses to the vaccine, which puts many endemic communities at risk for infection against HepB and other diseases that are preventable by vaccines.
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Sub-Saharan Africa has increased morbidity and mortality related to chronic obstructive pulmonary disease (COPD). COPD among people living with HIV (PLWH) has not been well studied in this region, where HIV/AIDS is endemic. Increasing evidence suggests that respiratory microbial composition plays a role in COPD severity. Therefore, we aimed to investigate microbiome patterns and associations among PLWH with COPD in Sub-Saharan Africa. We conducted a cross-sectional study of 200 adults stratified by HIV and COPD in rural Uganda. Induced sputum samples were collected as an easy-to-obtain proxy for the lower respiratory tract microbiota. We performed 16S rRNA gene sequencing and used PICRUSt2 (version 2.2.3) to infer the functional profiles of the microbial community. We used a statistical tool to detect changes in specific taxa that searches and adjusts for confounding factors such as antiretroviral therapy (ART), age, sex, and other participant characteristics. We could cluster the microbial community into three community types whose distribution was shown to be significantly impacted by HIV. Some genera, e.g., Veillonella, Actinomyces, Atopobium, and Filifactor, were significantly enriched in HIV-infected individuals, while the COPD status was significantly associated with Gammaproteobacteria and Selenomonas abundance. Furthermore, reduced bacterial richness and significant enrichment in Campylobacter were associated with HIV-COPD comorbidity. Functional prediction using PICRUSt2 revealed a significant depletion in glutamate degradation capacity pathways in HIV-positive patients. A comparison of our findings with an HIV cohort from the United Kingdom revealed significant differences in the sputum microbiome composition, irrespective of viral suppression. IMPORTANCE Even with ART available, HIV-infected individuals are at high risk of suffering comorbidities, as shown by the high prevalence of noninfectious lung diseases in the HIV population. Recent studies have suggested a role for the respiratory microbiota in driving chronic lung inflammation. The respiratory microbiota was significantly altered among PLWH, with disease persisting up to 3 years post-ART initiation and HIV suppression. The community structure and diversity of the sputum microbiota in COPD are associated with disease severity and clinical outcomes, both in stable COPD and during exacerbations. Therefore, a better understanding of the sputum microbiome among PLWH could improve COPD prognostic and risk stratification strategies. In this study, we observed that in a virologically suppressed HIV cohort in rural Uganda, we could show differences in sputum microbiota stratified by HIV and COPD, reduced bacterial richness, and significant enrichment in Campylobacter associated with HIV-COPD comorbidity.
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The estimated mortality rate of the SARS-CoV-2 pandemic varied greatly around the world with multiple countries in East, Central, and West Africa having significantly lower rates of COVID-19 related fatalities than many resource-rich nations with significantly earlier wide-spread access to life-saving vaccines. One possible reason for this lower mortality could be the presence of pre-existing cross-reactive immunological responses in these areas of the world. To explore this hypothesis, stored peripheral blood mononuclear cells (PBMC) from Ugandans collected from 2015-2017 prior to the COVID-19 pandemic (n=29) and from hospitalized Ugandan COVID-19 patients (n=3) were examined using flow-cytometry for the presence of pre-existing SARS-CoV-2 cross-reactive CD4+ and CD8+ T-cell populations using four T-cell epitope mega pools. Of pre-pandemic participants, 89.7% (26/29) had either CD4+ or CD8+, or both, SARS-CoV-2 specific T-cell responses. Specifically, CD4+ T-cell reactivity (72.4%) and CD8+ T-cell reactivity (65.5%) were relatively similar, and 13 participants (44.8%) had both types of cross-reactive types of T-cells present. There were no significant differences in response by sex in the population. The rates of cross-reactive T-cell populations in these Ugandans is higher than previous estimates from resource-rich countries like the United States (20-50% reactivity). It is unclear what role, if any, this cross-reactivity played in decreasing COVID-19 related mortality in Uganda and other African countries, but does suggest that a better understanding of global pre-existing immunological cross-reactivity could be an informative data of epidemiological intelligence moving forward.
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BACKGROUND: There is a need for new tools for the diagnosis of tuberculosis (TB) amongst patients who present at primary health care centers with symptoms suggestive of TB. OBJECTIVES: To assess the abilities of selected blood-based host biomarkers to discriminate between patients who self-presented with symptoms suggestive of TB and were subsequently diagnosed with pulmonary tuberculosis (PTB), other respiratory diseases (ORD) with latent Mycobacterium tuberculosis infection (ORD_LTBI) or ORD without latent infection (ORD_NoLTBI). METHODS: Presumptive TB patients (n = 161) were enrolled at a TB Clinic in Kampala, Uganda, and blood was collected. Participants were later classified as having PTB or ORD using standard microbiological confirmatory tests. Patients with ORD were subsequently classified as having LTBI or no LTBI using the QuantiFERON Gold-plus test. The concentrations of 27 host biomarkers were evaluated in patient sera using the Luminex platform, followed by an evaluation of their abilities to discriminate between PTB, ORD_LTBI, and ORD_NoLTBI. RESULTS: Multiple host biomarkers including IP10, IL6, IL2, IL1ß, TNFα, IFNγ, and IL12p70, were significantly different between patients with PTB (n = 55), ORDs (n = 106), and between PTB and the two ORD sub-groups. A bio-signature comprising IP10, IL6, TNFα IL1ß, IL1ra, and IL12p70 best diagnosed PTB disease, with an area under the ROC curve of 90. CONCLUSION: We identified host biomarkers that discriminated between different M.tb infection states amongst patients who presented with symptoms requiring investigation for TB. The biomarkers that showed diagnostic potential in our study may be considered as additional candidate markers for future active PTB rapid screening tests.
Subject(s)
Latent Tuberculosis , Mycobacterium tuberculosis , Tuberculosis, Pulmonary , Tuberculosis , Humans , Tumor Necrosis Factor-alpha , Chemokine CXCL10 , Mycobacterium tuberculosis/metabolism , Interleukin-6 , Uganda , Tuberculosis/metabolism , Latent Tuberculosis/diagnosis , Tuberculosis, Pulmonary/diagnosis , Biomarkers , Interleukin-12ABSTRACT
OBJECTIVES: To explore whether community health worker household-based maternal health visits improve antenatal care and skilled birth attendance among hard-to-reach fishing villages on Lake Victoria, Uganda. METHODS: This quasi-experimental 18-month prospective study involved 486 consenting women aged 15-49 years, who were pregnant or had a pregnancy outcome in the past 6 months, from 6 island fishing communities. The community health worker household-based intervention (community health workers' household visits to provide counseling, blood pressure measurement, anemia, and HIV testing) involved 243 women from three fishing communities. Random effects logistic regression was used to determine the association between the community health worker intervention and antenatal care and skilled birth attendance among women who had at least 5 months of pregnancy or childbirth at follow-up. RESULTS: Almost all women accepted the community health worker intervention (90.9% (221/243)). Hypertension was at 12.5% (27/216) among those who accepted blood pressure measurements, a third (33.3% (9/27)) were pregnant. HIV prevalence was 23.5% (52/221). Over a third (34.2% (69/202)) of women tested had anemia (hemoglobin levels less than 11 g/dL). The community health worker intervention was associated with attendance of first antenatal care visit within 20 weeks of pregnancy (adjusted odd ratio = 2.1 (95% confidence interval 0.6-7.6)), attendance of at least four antenatal care visits (adjusted odd ratio = 0.9 (95% confidence interval 0.4-2.0)), and skilled birth attendance (adjusted odd ratio = 0.5 (95% confidence interval 0.1-1.5)), though not statistically significant. CONCLUSION: Community health workers have a crucial role in improving early antenatal care attendance, early community-based diagnosis of anemia, hypertensive disorders, and HIV among women in these hard-to-reach fishing communities.
Subject(s)
HIV Infections , Hypertension , Maternal Health Services , Community Health Workers , Female , HIV Infections/diagnosis , HIV Infections/epidemiology , Humans , Hunting , Pregnancy , Prenatal Care , Prospective Studies , Uganda/epidemiologyABSTRACT
Objective: The observation that HIV-1 subtype D progresses faster to disease than subtype A prompted us to examine cytokine levels early after infection within the predominant viral subtypes that circulate in Uganda and address the following research questions: (1) Do cytokine levels vary between subtypes A1 and D? (2) Do cytokine profiles correlate with disease outcomes? Methods: To address these questions, HIV-1 subtypes were determined by population sequencing of the HIV-1 pol gene and 37 plasma cytokine concentrations were evaluated using V-Plex kits on Meso Scale Discovery platform in 65 recent sero-converters. Results: HIV-1 subtype D (pol) infections exhibited significantly higher median plasma concentrations of IL-5, IL-16, IL-1α, IL-7, IL-17A, CCL11 (Eotaxin-1), CXCL10 (IP-10), CCL13 (MCP-4) and VEGF-D compared to subtype A1 (pol) infections. We also found that IL-12/23p40 and IL-1α were associated with faster CD4+T cell count decline, while bFGF was associated with maintenance of CD4+ counts above 350 cells/microliter. Conclusion: Our results suggest that increased production of cytokines in early HIV infection may trigger a disruption of the immune environment and contribute to pathogenic mechanisms underlying the accelerated disease progression seen in individuals infected with HIV-1 subtype D in Uganda.
ABSTRACT
INTRODUCTION: Family planning knowledge is poor and use is low in Ugandan fishing communities. We compared the effectiveness of enhanced family planning (FP) education with routine counselling on FP knowledge and use. METHODS: Individuals aged 15-49 years were randomly assigned to intervention or control arm. The intervention constituted enhanced FP education based on a simplified handout extracted from the WHO FP guidance tool called, "Family planning: A global handbook for FP providers" which participants took home for additional reading. The control arm constituted FP counselling following Uganda Ministry of Health guidelines. FP knowledge score and contraceptive prevalence rate (CPR) were compared between trial arms at baseline and at 12 months. Negative binomial regression models were used to estimate the effect of the intervention on FP knowledge and use. RESULTS: Overall, 1410 participants were screened to enrol 1004 (502 per study arm, 48.5% women). Subsequently, 384 (76.5%) and 383 (76.3%) completed the 12 months' follow-up in the intervention and control arms respectively. At baseline, a median FP knowledge score of 8 and a < 70% FP knowledge score was observed for all participants with a CPR of 36.8%. At month-12, the median FP knowledge score improved in both arms, higher in the intervention arm than the control arm (46 vs 30; p < 0.001). In the intervention arm, 304 (79.2%) had a score of ≥70 compared with 21 (5.5%) in the control arm (p < 0.001). In the negative binomial regression model, the change in FP knowledge score was 47% higher in the intervention arm than in the control arm (score ratio: 1.47, 95%CI: 1. 43-1.51, p < 0.001). The change in CPR was 16% higher in the intervention arm than in the control arm (Prevalence ratio: 1.16, 95%CI: 1.01-1.34, p < 0.040). INTERPRETATION: Enhanced FP education using a simplified FP education handout was more effective in increasing FP knowledge and use compared to routine FP counselling for people living in fishing communities. Innovative FP education interventions are recommended for improving FP knowledge and optimizing uptake in remote-rural settings where literacy levels are low. TRIAL REGISTRATION: The study was registered by the Pan African Clinical Trial Registry on 03 July 2021 with a Trial Registration Number PACTR202107891858045 . "Retrospectively registered".