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Journal articleSilhol R, Maheu-Giroux M, Soni N, et al., 2024,
The impact of past HIV interventions and diagnosis gaps on new HIV acquisitions, transmissions, and HIV-related deaths in Côte d’Ivoire, Mali, and Senegal
, AIDS, Vol: 38, Pages: 1783-1793, ISSN: 0269-9370Objectives: To estimate the epidemiological impact of past HIV interventions and the magnitude and contribution of undiagnosed HIV among different risk groups on new HIV acquisitions in Côte d’Ivoire, Mali and Senegal.Design: HIV transmission dynamic models among the overall population and key populations [female sex workers (FSW), their clients, and MSM].Methods: Models were independently parameterized and calibrated for each set of country-specific demographic, behavioural, and epidemiological data. We estimated the fraction of new HIV infections over 2012–2021 averted by condom use and antiretroviral therapy (ART) uptake among key population and nonkey population, the direct and indirect contribution of specific groups to new infections [transmission population-attributable fraction (tPAF)] over 2012–2021 due to prevention gaps, and the distribution of undiagnosed PWH by risk group in January 2022 and their tPAF over 2022–2031.Results: Condom use and ART may have averted 81–88% of new HIV infections over 2012–2021 across countries, mostly because of condom use by key population. The tPAF of all key populations combined over 2012–2021 varied between 27% (Côte d’Ivoire) and 79% (Senegal). Male key population (clients of FSW and MSM) contributed most to new infections (>60% in Mali and Senegal) owing to their higher HIV prevalence and larger prevention gaps. In 2022, men represented 56% of all PWH with an undiagnosed infection in Côte d’Ivoire (male key population = 15%), 46% in Mali (male key population = 23%), and 69% in Senegal (male key population = 55%). If HIV testing and ART initiation rates remain at current levels, 20% of new HIV infections could be due to undiagnosed key population PWH in Côte d’Ivoire over 2022–2031, 53% in Mali, and 65% in Senegal.Conclusion: Substantial HIV diagnosis gaps remain in Western Africa, especially among male key population. Addressing
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Journal articleMilne GC, Oettle RC, Whittaker C, et al., 2024,
Revisiting immunity vs. exposure in schistosomiasis: a mathematical modeling study of delayed concomitant immunity
, PNAS Nexus, Vol: 3, ISSN: 2752-6542The relative contributions of exposure vs. acquired immunity to the epidemiology of human schistosomiasis has been long debated. While there is considerable evidence that humans acquire partial immunity to infection, age- and sex-related contact patterns with water bodies contaminated with infectious cercarial schistosome larvae also contribute to typical epidemiological profiles of infection. Here, we develop a novel schistosome transmission model that incorporates both partially protective “delayed concomitant” acquired immunity—stimulated by dying worms—and host age- and sex-dependent patterns of exposure. We use a contemporary Bayesian approach to fit the model to historical individual data on exposure to infectious cercaria, eggs per gram of feces, and immunoglobulin E antibodies specific to Schistosoma mansoni Tegumental-Allergen-Like protein 1 collected from a highly endemic community in Uganda, estimating the relative contributions of exposure and acquired immunity. We find that model variants incorporating or omitting delayed concomitant immunity describe equally well the age- and sex-specific immunoepidemiological patterns observed before intervention and 18 months after treatment. Over longer time horizons, we find that acquired immunity creates subtle differences in immunoepidemiological profiles during routine mass drug administration that may confer resilience against elimination. We discuss our findings in the broader context of the immunoepidemiology of schistosomiasis.
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Journal articleMeyer-Rath G, Imai-Eaton JW, 2024,
Optimising HIV spending in eastern Europe and central Asia.
, Lancet HIV, Vol: 11, Pages: e654-e655 -
Journal articleBelcher RN, Murray KA, Reeves JP, et al., 2024,
Socioeconomic deprivation modifies green space and mental health associations: a within-person study
, Environment International, Vol: 192, ISSN: 0160-4120Living in an area with good availability and accessibility of residential green spaces such as parks, woodlands, and residential gardens can improve mental health and reduce the global disease burden. Unlike for physical health, it is not well understood if mental health and green space associations might be modified by local area deprivation. Existing evidence for this association comes from cross-sectional studies, widely considered vulnerable to confounding and bias. Individual time-invariant mental health status, personality, and other factors may result in positive effect modification on green space and mental health associations in more deprived areas. We use fixed-effects models that remove time-invariant confounding by calculating differences within-persons to eliminate this bias and add to the existing evidence. We modelled changes in mental health status, green space, and deprivation (relative to the within-person mean) within 54,666 individuals with a combined total of 300,710 mental health scores from one of the world’s largest panel surveys: “Understanding Society” in the UK. We found a positive effect of increasing residential green space on mental health and this was positively modified and intensified by area deprivation before and after adjusting for confounding. Our results support providing green space to protect against the negative impact of socioeconomic deprivation on health, particularly for those moving from a less deprived to a more deprived area.
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Journal articleMangal TD, Mohan S, Colbourn T, et al., 2024,
Assessing the effect of health system resources on HIV and tuberculosis programmes in Malawi: a modelling study
, The Lancet Global Health, Vol: 12, Pages: e1638-e1648, ISSN: 2214-109XBACKGROUND: Malawi is progressing towards UNAIDS and WHO End TB Strategy targets to eliminate HIV/AIDS and tuberculosis. We aimed to assess the prospective effect of achieving these goals on the health and health system of the country and the influence of consumable constraints. METHODS: In this modelling study, we used the Thanzi la Onse (Health for All) model, which is an individual-based multi-disease simulation model that simulates HIV and tuberculosis transmission, alongside other diseases (eg, malaria, non-communicable diseases, and maternal diseases), and gates access to essential medicines according to empirical estimates of availability. The model integrates dynamic disease modelling with health system engagement behaviour, health system use, and capabilities (ie, personnel and consumables). We used 2018 data on the availability of HIV and tuberculosis consumables (for testing, treatment, and prevention) across all facility levels of the country to model three scenarios of HIV and tuberculosis programme scale-up from Jan 1, 2023, to Dec 31, 2033: a baseline scenario, when coverage remains static using existing consumable constraints; a constrained scenario, in which prioritised interventions are scaled up with fixed consumable constraints; and an unconstrained scenario, in which prioritised interventions are scaled up with maximum availability of all consumables related to HIV and tuberculosis care. FINDINGS: With uninterrupted medical supplies, in Malawi, we projected HIV and tuberculosis incidence to decrease to 26 (95% uncertainty interval [UI] 19-35) cases and 55 (23-74) cases per 100 000 person-years by 2033 (from 152 [98-195] cases and 123 [99-160] cases per 100 000 person-years in 2023), respectively, with programme scale-up, averting a total of 12·21 million (95% UI 11·39-14·16) disability-adjusted life-years. However, the effect was compromised by restricted access to key medicines, resulting in approximately 58 700 additional
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Journal articleHuybrechts I, Chimera B, Hanley-Cook GT, et al., 2024,
Food biodiversity and gastrointestinal cancer risk in nine European countries: analysis within a prospective cohort study
, European Journal of Cancer, Vol: 210, ISSN: 0959-8049BackgroundFood biodiversity in human diets has potential co-benefits for both public health and sustainable food systems. However, current evidence on the potential relationship between food biodiversity and cancer risk, and particularly gastrointestinal cancers typically related to diet, remains limited. This study evaluated how dietary species richness (DSR) was associated with gastrointestinal cancer risk in a pan-European population.MethodsAssociations between DSR and subsequent gastrointestinal cancer risk were examined among 450,111 adults enrolled in the European Prospective Investigation into Cancer and Nutrition cohort (EPIC, initiated in 1992), free of cancer at baseline. Usual dietary intakes were assessed at recruitment with country-specific dietary questionnaires. DSR of an individual’s yearly diet was calculated based on the absolute number of unique biological species in each food and drink item. Associations between DSR and cancer risk were assessed by multivariable Cox proportional hazards regression models.FindingsDuring a median follow-up time of 14.1 years (SD=3.9), 10,705 participants were diagnosed with gastrointestinal cancer. Hazard ratios (HRs) and 95 % confidence intervals (CIs) comparing overall gastrointestinal cancer risk in the highest versus lowest quintiles of DSR indicated inverse associations in multivariable-adjusted models [HR (95 % CI): 0.77 (0.69–0.87); P-value < 0·0001] (Table 2). Specifically, inverse associations were observed between DSR and oesophageal squamous cell carcinoma, proximal colon, colorectal, and liver cancer risk (p-trend<0.05 for all cancer types).InterpretationGreater food biodiversity in the diet may lower the risk of certain gastrointestinal cancers. Further research is needed to replicate these novel findings and to understand potential mechanisms.
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Journal articleBonell A, Vicedo-Cabrera AM, Moirano G, et al., 2024,
Effect of heat stress in the first 1000 days of life on fetal and infant growth: a secondary analysis of the ENID randomised controlled trial.
, Lancet Planet Health, Vol: 8, Pages: e734-e743BACKGROUND: The intersecting crises of climate change, food insecurity, and undernutrition disproportionately affect children. Understanding the effect of heat on growth from conception to 2 years of age is important because of mortality and morbidity implications in the near term and over the life course. METHODS: In this secondary analysis, we used longitudinal pregnancy cohort data from the Early Nutrition and Immunity Development (ENID) randomised controlled trial in West Kiang, The Gambia, which occurred between Jan 20, 2010, and Feb 10, 2015. The ENID trial assessed micronutrient supplementation in the first 1000 days of life starting from 20 weeks' gestation, during which anthropometric measurements were collected prospectively. We used multivariable linear regression to assess the effect of heat stress (defined by Universal Thermal Climate Index [UTCI]) on intrauterine growth restriction based on length-for-gestational age Z score (LGAZ), weight-for-gestational age Z score (WGAZ), and head circumference-for-gestational age Z score (HCGAZ) at birth, and assessed for effect modification of supplement intervention on the relationship between heat stress and infant anthropometry. We used multivariable, multilevel linear regression to evaluate the effect of heat stress on infant growth postnatally based on weight-for-height Z score (WHZ), weight-for-age Z score (WAZ), and height-for-age Z score (HAZ) from 0 to 2 years of age. FINDINGS: Complete data were available for 668 livebirth outcomes (329 [49%] female infants and 339 [51%] male infants). With each 1°C increase in mean daily maximum UTCI exposure, in the first trimester, we observed a reduction in WGAZ (-0·04 [95% CI -0·09 to 0·00]), whereas in the third trimester, we observed an increase in HCGAZ (0·06 [95% CI 0·00 to 0·12]), although 95% CIs included 0. Maternal protein-energy supplementation in the third trimester was associated with reduced WGAZ (-0·1
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Journal articleSchnizer M, Schellong P, Rose N, et al., 2024,
Long versus short course anti-microbial therapy of uncomplicated Staphylococcus aureus bacteraemia: a systematic review.
, Clin Microbiol Infect, Vol: 30, Pages: 1254-1260BACKGROUND: Current guidelines recommend at least 2 weeks duration of antibiotic therapy (DOT) for patients with uncomplicated Staphylococcus aureus bacteraemia (SAB) but the evidence for this recommendation is unclear. OBJECTIVES: To perform a systematic literature review assessing current evidence for recommended DOT for patients with SAB. METHODS: The following are the methods used for this study. DATA SOURCES: We searched MEDLINE, ISI Web of Science, the Cochrane Database and clinicaltrials.gov from inception to March 30, 2024. References of eligible studies were screened and experts in the field contacted for additional articles. STUDY ELIGIBILITY CRITERIA: All clinical studies, regardless of design, publication status and language. PARTICIPANTS: Adult patients with uncomplicated SAB. INTERVENTIONS: Long (>14 days; >18 days; 11-16 days) vs. short (≤14 days; 10-18 days; 6-10 days, respectively) DOT with the DOT being defined as the first until the last day of antibiotic therapy. ASSESSMENT OF RISK OF BIAS: Risk of bias was assessed using the ROBINS-I-tool. METHODS OF DATA SYNTHESIS: The primary outcome was 90-day all-cause mortality. Only studies presenting results of adjusted analyses for mortality were included. Data synthesis could not be performed. RESULTS: Eleven nonrandomized studies were identified that fulfilled the pre-defined inclusion criteria, of which three studies reported adjusted effect ratios. Only these were included in the final analysis. We did not find any RCT. Two studies with 1230 patients reported the primary endpoint 90-day all-cause mortality. Neither found a statistically significant superiority for longer (>14 days; 11-16 days) or shorter DOT (≤14 days; 6-10 days, respectively) for patients with uncomplicated SAB. Two studies investigated the secondary endpoint 30-day all-cause mortality (>18 days; 11-16 days vs. 10-18 days; 6-10 days, respect
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Journal articlePerez Guzman PN, Longa Chanda S, Schaap A, et al., 2024,
Pandemic burden in low-income settings and impact of limited and delayed interventions: a granular modelling analysis of COVID-19 in Kabwe, Zambia
, International Journal of Infectious Diseases, Vol: 147, ISSN: 1201-9712ObjectivesPandemic response in low-income countries (LICs) or settings often suffers from scarce epidemic surveillance and constrained mitigation capacity. The drivers of pandemic burden in such settings, and the impact of limited and delayed interventions remain poorly understood.MethodsWe analysed COVID-19 seroprevalence and all-cause excess deaths data from the peri-urban district of Kabwe, Zambia between March 2020 and September 2021 with a novel mathematical model. Data encompassed three consecutive waves caused by the wild-type, Beta and Delta variants.ResultsAcross all three waves, we estimated a high cumulative attack rate, with 78% (95% credible interval [CrI] 71-85) of the population infected, and a high all-cause excess mortality, at 402 (95% CrI 277-473) deaths per 100,000 people. Ambitiously improving health care to a capacity similar to that in high-income settings could have averted up to 46% (95% CrI 41-53) of accrued excess deaths, if implemented from June 2020 onward. An early and accelerated vaccination rollout could have achieved the highest reductions in deaths. Had vaccination started as in some high-income settings in December 2020 and with the same daily capacity (doses per 100 population), up to 68% (95% CrI 64-71) of accrued excess deaths could have been averted. Slower rollouts would have still averted 62% (95% CrI 58-68), 54% (95% CrI 49-61) or 26% (95% CrI 20-38) of excess deaths if matching the average vaccination capacity of upper-middle-, lower-middle- or LICs, respectively.ConclusionsRobust quantitative analyses of pandemic data are of pressing need to inform future global pandemic preparedness commitments.
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Journal articleMills C, Chadeau-Hyam M, Elliott P, et al., 2024,
The utility of wastewater surveillance for monitoring SARS-CoV-2 prevalence
, PNAS Nexus, Vol: 3, ISSN: 2752-6542Public health authorities have increasingly used wastewater-based epidemiology (WBE) to monitor community transmission of SARS-CoV-2 and other agents. Here, we evaluate the utility of WBE during the COVID-19 pandemic in England for estimating SARS-CoV-2 prevalence. We use wastewater data from the Environmental Monitoring for Health Protection (EMHP) programme and prevalence data from the REal-time Assessment of Community Transmission-1 (REACT-1) study. Across the pandemic, we describe how wastewater-based modelling can achieve representative SARS-CoV-2 prevalence estimates in fine and coarse spatial resolutions for relatively short time horizons (of up to one month), and thus assist in filling temporal gaps in surveillance. We infer a temporally evolving relationship between wastewater and prevalence which may limit the utility of WBE for estimating SARS-CoV-2 prevalence over longer time horizons without a concurrent prevalence survey. Exploring further our finding of time-varying, population-level faecal shedding, we characterise WBE for SARS-CoV-2 prevalence as i) vaccination-coverage-dependent and ii) variant-specific. Our research suggests that these factors are important considerations in future uses of WBE by public health authorities in infectious disease outbreaks. We further demonstrate that WBE can improve both the cost efficiency and accuracy of community prevalence surveys which on their own may have incomplete geographic coverage and/or small sample sizes. Therefore, in England, for the objective of high spatial resolution prevalence monitoring, strategic use of SARS-CoV-2 wastewater concentration data nationally could have enhanced, but not replaced, community prevalence survey programmes.
This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.
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