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Journal articleAliaga-Samanez A, Romero D, Murray K, et al., 2024,
Climate change is aggravating dengue and yellow fever transmission risk
, Ecography, Vol: 2024, ISSN: 0906-7590Dengue and yellow fever have complex cycles, involving urban and sylvatic mosquitoes, and non-human primate hosts. To date, efforts to assess the effect of climate change on these diseases have neglected the combination of such crucial factors. Recent studies only considered urban vectors. This is the first study to include them together with sylvatic vectors and the distribution of primates to analyse the effect of climate change on these diseases. We used previously published models, based on machine learning algorithms and fuzzy logic, to identify areas where climatic favourability for the relevant transmission agents could change: 1) favourable areas for the circulation of the viruses due to the environment and to non-human primate distributions; 2) the favourability for urban and sylvatic vectors. We obtained projections of future transmission risk for two future periods and for each disease, and implemented uncertainty analyses to test for predictions reliability. Areas currently favourable for both diseases could keep being climatically favourable, while global favourability could increase a 7% for yellow fever and a 10% increase for dengue. Areas likely to be more affected in the future for dengue include West Africa, South Asia, the Gulf of Mexico, Central America and the Amazon basin. A possible spread of dengue could take place into Europe, the Mediterranean basin, the UK and Portugal; and, in Asia, into northern China. For yellow fever, climate could become more favourable in Central and Southeast Africa; India; and in north and southeast South America, including Brazil, Paraguay, Bolivia, Peru, Colombia and Venezuela. In Brazil, favourability for yellow fever will probably increase in the south, the west and the east. Areas where the transmission risk spread is consistent to the dispersal of vectors are highlighted in respect of areas where the expected spread is directly attributable to environmental changes. Both scenarios could involve different prev
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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 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 articleWoodroffe R, Astley K, Barnecut R, et al., 2024,
Farmer-led badger vaccination in Cornwall: Epidemiological patterns and social perspectives
, PEOPLE AND NATURE, Vol: 6, Pages: 1960-1973 -
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 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 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 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 articleDerelle R, von Wachsmann J, Maklin T, et al., 2024,
Seamless, rapid, and accurate analyses of outbreak genomic data using split <i>k</i>-mer analysis
, GENOME RESEARCH, Vol: 34, Pages: 1661-1673, ISSN: 1088-9051 -
Journal articleMajeed A, Quint JK, Bhatt S, et al., 2024,
Non-pharmaceutical interventions: evaluating challenges and priorities for future health shocks
, BMJ, Vol: 387, ISSN: 0959-8138
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