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  1. Article ; Online: Treatment selection in multi-arm multi-stage designs: With application to a postpartum haemorrhage trial.

    Choodari-Oskooei, Babak / Thwin, Soe Soe / Blenkinsop, Alexandra / Widmer, Mariana / Althabe, Fernando / Parmar, Mahesh Kb

    Clinical trials (London, England)

    2023  Volume 20, Issue 1, Page(s) 71–80

    Abstract: Background: Multi-arm multi-stage trials are an efficient, adaptive approach for testing many treatments simultaneously within one protocol. In settings where numbers of patients available to be entered into trials and resources might be limited, such ... ...

    Abstract Background: Multi-arm multi-stage trials are an efficient, adaptive approach for testing many treatments simultaneously within one protocol. In settings where numbers of patients available to be entered into trials and resources might be limited, such as primary postpartum haemorrhage, it may be necessary to select a pre-specified subset of arms at interim stages even if they are all showing some promise against the control arm. This will put a limit on the maximum number of patients required and reduce the associated costs. Motivated by the World Health Organization Refractory HaEmorrhage Devices trial in postpartum haemorrhage, we explored the properties of such a selection design in a randomised phase III setting and compared it with other alternatives. The objectives are: (1) to investigate how the timing of treatment selection affects the operating characteristics; (2) to explore the use of an information-rich (continuous) intermediate outcome to select the best-performing arm, out of four treatment arms, compared with using the primary (binary) outcome for selection at the interim stage; and (3) to identify factors that can affect the efficiency of the design.
    Methods: We conducted simulations based on the refractory haemorrhage devices multi-arm multi-stage selection trial to investigate the impact of the timing of treatment selection and applying an adaptive allocation ratio on the probability of correct selection, overall power and familywise type I error rate. Simulations were also conducted to explore how other design parameters will affect both the maximum sample size and trial timelines.
    Results: The results indicate that the overall power of the trial is bounded by the probability of 'correct' selection at the selection stage. The results showed that good operating characteristics are achieved if the treatment selection is conducted at around 17% of information time. Our results also showed that although randomising more patients to research arms before selection will increase the probability of selecting correctly, this will not increase the overall efficiency of the (selection) design compared with the fixed allocation ratio of 1:1 to all arms throughout.
    Conclusions: Multi-arm multi-stage selection designs are efficient and flexible with desirable operating characteristics. We give guidance on many aspects of these designs including selecting the intermediate outcome measure, the timing of treatment selection, and choosing the operating characteristics.
    MeSH term(s) Female ; Humans ; Research Design ; Postpartum Hemorrhage/therapy ; Sample Size ; Patient Selection ; Outcome Assessment, Health Care
    Language English
    Publishing date 2023-01-17
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2138796-5
    ISSN 1740-7753 ; 1740-7745
    ISSN (online) 1740-7753
    ISSN 1740-7745
    DOI 10.1177/17407745221136527
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: List child dependents on death certificates.

    Flaxman, Seth / Kasonka, Lackson / Cluver, Lucie / Souza, Andrea Santos / Nelson, Charles A / Blenkinsop, Alexandra / Unwin, H Juliette T / Hillis, Susan

    Science (New York, N.Y.)

    2023  Volume 380, Issue 6644, Page(s) 467

    MeSH term(s) Child ; Humans ; Child, Orphaned ; COVID-19/mortality ; Death Certificates ; Models, Statistical ; Cause of Death
    Language English
    Publishing date 2023-05-04
    Publishing country United States
    Document type Letter
    ZDB-ID 128410-1
    ISSN 1095-9203 ; 0036-8075
    ISSN (online) 1095-9203
    ISSN 0036-8075
    DOI 10.1126/science.adh8784
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Assessing the impact of efficacy stopping rules on the error rates under the multi-arm multi-stage framework.

    Blenkinsop, Alexandra / Parmar, Mahesh Kb / Choodari-Oskooei, Babak

    Clinical trials (London, England)

    2019  Volume 16, Issue 2, Page(s) 132–141

    Abstract: Background: The multi-arm multi-stage framework uses intermediate outcomes to assess lack-of-benefit of research arms at interim stages in randomised trials with time-to-event outcomes. However, the design lacks formal methods to evaluate early evidence ...

    Abstract Background: The multi-arm multi-stage framework uses intermediate outcomes to assess lack-of-benefit of research arms at interim stages in randomised trials with time-to-event outcomes. However, the design lacks formal methods to evaluate early evidence of overwhelming efficacy on the definitive outcome measure. We explore the operating characteristics of this extension to the multi-arm multi-stage design and how to control the pairwise and familywise type I error rate. Using real examples and the updated nstage program, we demonstrate how such a design can be developed in practice.
    Methods: We used the Dunnett approach for assessing treatment arms when conducting comprehensive simulation studies to evaluate the familywise error rate, with and without interim efficacy looks on the definitive outcome measure, at the same time as the planned lack-of-benefit interim analyses on the intermediate outcome measure. We studied the effect of the timing of interim analyses, allocation ratio, lack-of-benefit boundaries, efficacy rule, number of stages and research arms on the operating characteristics of the design when efficacy stopping boundaries are incorporated. Methods for controlling the familywise error rate with efficacy looks were also addressed.
    Results: Incorporating Haybittle-Peto stopping boundaries on the definitive outcome at the interim analyses will not inflate the familywise error rate in a multi-arm design with two stages. However, this rule is conservative; in general, more liberal stopping boundaries can be used with minimal impact on the familywise error rate. Efficacy bounds in trials with three or more stages using an intermediate outcome may inflate the familywise error rate, but we show how to maintain strong control.
    Conclusion: The multi-arm multi-stage design allows stopping for both lack-of-benefit on the intermediate outcome and efficacy on the definitive outcome at the interim stages. We provide guidelines on how to control the familywise error rate when efficacy boundaries are implemented in practice.
    MeSH term(s) Bias ; Computer Simulation ; Data Interpretation, Statistical ; Endpoint Determination ; Humans ; Randomized Controlled Trials as Topic/methods ; Randomized Controlled Trials as Topic/standards ; Reproducibility of Results ; Research Design ; Time Factors
    Language English
    Publishing date 2019-01-16
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2138796-5
    ISSN 1740-7753 ; 1740-7745
    ISSN (online) 1740-7753
    ISSN 1740-7745
    DOI 10.1177/1740774518823551
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Assessment of COVID-19 as the Underlying Cause of Death Among Children and Young People Aged 0 to 19 Years in the US.

    Flaxman, Seth / Whittaker, Charles / Semenova, Elizaveta / Rashid, Theo / Parks, Robbie M / Blenkinsop, Alexandra / Unwin, H Juliette T / Mishra, Swapnil / Bhatt, Samir / Gurdasani, Deepti / Ratmann, Oliver

    JAMA network open

    2023  Volume 6, Issue 1, Page(s) e2253590

    Abstract: Importance: COVID-19 was the underlying cause of death for more than 940 000 individuals in the US, including at least 1289 children and young people (CYP) aged 0 to 19 years, with at least 821 CYP deaths occurring in the 1-year period from August 1, ... ...

    Abstract Importance: COVID-19 was the underlying cause of death for more than 940 000 individuals in the US, including at least 1289 children and young people (CYP) aged 0 to 19 years, with at least 821 CYP deaths occurring in the 1-year period from August 1, 2021, to July 31, 2022. Because deaths among US CYP are rare, the mortality burden of COVID-19 in CYP is best understood in the context of all other causes of CYP death.
    Objective: To determine whether COVID-19 is a leading (top 10) cause of death in CYP in the US.
    Design, setting, and participants: This national population-level cross-sectional epidemiological analysis for the years 2019 to 2022 used data from the US Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research (WONDER) database on underlying cause of death in the US to identify the ranking of COVID-19 relative to other causes of death among individuals aged 0 to 19 years. COVID-19 deaths were considered in 12-month periods between April 1, 2020, and August 31, 2022, compared with deaths from leading non-COVID-19 causes in 2019, 2020, and 2021.
    Main outcomes and measures: Cause of death rankings by total number of deaths, crude rates per 100 000 population, and percentage of all causes of death, using the National Center for Health Statistics 113 Selected Causes of Death, for ages 0 to 19 and by age groupings (<1 year, 1-4 years, 5-9 years, 10-14 years, 15-19 years).
    Results: There were 821 COVID-19 deaths among individuals aged 0 to 19 years during the study period, resulting in a crude death rate of 1.0 per 100 000 population overall; 4.3 per 100 000 for those younger than 1 year; 0.6 per 100 000 for those aged 1 to 4 years; 0.4 per 100 000 for those aged 5 to 9 years; 0.5 per 100 000 for those aged 10 to 14 years; and 1.8 per 100 000 for those aged 15 to 19 years. COVID-19 mortality in the time period of August 1, 2021, to July 31, 2022, was among the 10 leading causes of death in CYP aged 0 to 19 years in the US, ranking eighth among all causes of deaths, fifth in disease-related causes of deaths (excluding unintentional injuries, assault, and suicide), and first in deaths caused by infectious or respiratory diseases when compared with 2019. COVID-19 deaths constituted 2% of all causes of death in this age group.
    Conclusions and relevance: The findings of this study suggest that COVID-19 was a leading cause of death in CYP. It caused substantially more deaths in CYP annually than any vaccine-preventable disease historically in the recent period before vaccines became available. Various factors, including underreporting and not accounting for COVID-19's role as a contributing cause of death from other diseases, mean that these estimates may understate the true mortality burden of COVID-19. The findings of this study underscore the public health relevance of COVID-19 to CYP. In the likely future context of sustained SARS-CoV-2 circulation, appropriate pharmaceutical and nonpharmaceutical interventions (eg, vaccines, ventilation, air cleaning) will continue to play an important role in limiting transmission of the virus and mitigating severe disease in CYP.
    MeSH term(s) Child ; Humans ; Adolescent ; Cause of Death ; COVID-19 ; Cross-Sectional Studies ; SARS-CoV-2 ; Communicable Diseases
    Language English
    Publishing date 2023-01-03
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ISSN 2574-3805
    ISSN (online) 2574-3805
    DOI 10.1001/jamanetworkopen.2022.53590
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Book ; Online: Sources of HIV infections among MSM with a migration background

    Blenkinsop, Alexandra / Pantazis, Nikos / Kostaki, Evangelia Georgia / Sofocleous, Lysandros / van Sighem, Ard / Bezemer, Daniela / van de Laar, Thijs / van der Valk, Marc / Reiss, Peter / de Bree, Godelieve / Ratmann, Oliver

    a viral phylogenetic case study in Amsterdam, the Netherlands

    2024  

    Abstract: Background: Men and women with a migration background comprise an increasing proportion of incident HIV cases across Western Europe. Several studies indicate a substantial proportion acquire HIV post-migration. Methods: We used partial HIV consensus ... ...

    Abstract Background: Men and women with a migration background comprise an increasing proportion of incident HIV cases across Western Europe. Several studies indicate a substantial proportion acquire HIV post-migration. Methods: We used partial HIV consensus sequences with linked demographic and clinical data from the opt-out ATHENA cohort of people with HIV in the Netherlands to quantify population-level sources of transmission to Dutch-born and foreign-born Amsterdam men who have sex with men (MSM) between 2010-2021. We identified phylogenetically and epidemiologically possible transmission pairs in local transmission chains and interpreted these in the context of estimated infection dates, quantifying transmission dynamics between sub-populations by world region of birth. Results: We estimate the majority of Amsterdam MSM who acquired their infection locally had a Dutch-born Amsterdam MSM source (56% [53-58%]). Dutch-born MSM were the predominant source population of infections among almost all foreign-born Amsterdam MSM sub-populations. Stratifying by two-year intervals indicated shifts in transmission dynamics, with a majority of infections originating from foreign-born MSM since 2018, although uncertainty ranges remained wide. Conclusions: In the context of declining HIV incidence among Amsterdam MSM, our data suggest whilst native-born MSM have predominantly driven transmissions in 2010-2021, the contribution from foreign-born MSM living in Amsterdam is increasing.
    Keywords Quantitative Biology - Populations and Evolution
    Publishing date 2024-01-16
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article: Age and gender profiles of HIV infection burden and viraemia: novel metrics for HIV epidemic control in African populations with high antiretroviral therapy coverage.

    Brizzi, Andrea / Kagaayi, Joseph / Ssekubugu, Robert / Abeler-Dörner, Lucie / Blenkinsop, Alexandra / Bonsall, David / Chang, Larry W / Fraser, Christophe / Galiwango, Ronald M / Kigozi, Godfrey / Kyle, Imogen / Monod, Mélodie / Nakigozi, Gertrude / Nalugoda, Fred / Rosen, Joseph G / Laeyendecker, Oliver / Quinn, Thomas C / Grabowski, M Kate / Reynolds, Steven J /
    Ratmann, Oliver

    medRxiv : the preprint server for health sciences

    2024  

    Abstract: Introduction: To prioritize and tailor interventions for ending AIDS by 2030 in Africa, it is important to characterize the population groups in which HIV viraemia is concentrating.: Methods: We analysed HIV testing and viral load data collected ... ...

    Abstract Introduction: To prioritize and tailor interventions for ending AIDS by 2030 in Africa, it is important to characterize the population groups in which HIV viraemia is concentrating.
    Methods: We analysed HIV testing and viral load data collected between 2013-2019 from the open, population-based Rakai Community Cohort Study (RCCS) in Uganda, to estimate HIV seroprevalence and population viral suppression over time by gender, one-year age bands and residence in inland and fishing communities. All estimates were standardized to the underlying source population using census data. We then assessed 95-95-95 targets in their ability to identify the populations in which viraemia concentrates.
    Results: Following the implementation of Universal Test and Treat, the proportion of individuals with viraemia decreased from 4.9% (4.6%-5.3%) in 2013 to 1.9% (1.7%-2.2%) in 2019 in inland communities and from 19.1% (18.0%-20.4%) in 2013 to 4.7% (4.0%-5.5%) in 2019 in fishing communities. Viraemia did not concentrate in the age and gender groups furthest from achieving 95-95-95 targets. Instead, in both inland and fishing communities, women aged 25-29 and men aged 30-34 were the 5-year age groups that contributed most to population-level viraemia in 2019, despite these groups being close to or had already achieved 95-95-95 targets.
    Conclusions: The 95-95-95 targets provide a useful benchmark for monitoring progress towards HIV epidemic control, but do not contextualize underlying population structures and so may direct interventions towards groups that represent a marginal fraction of the population with viraemia.
    Language English
    Publishing date 2024-04-22
    Publishing country United States
    Document type Preprint
    DOI 10.1101/2024.04.21.24306145
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Estimating the potential to prevent locally acquired HIV infections in a UNAIDS Fast-Track City, Amsterdam.

    Blenkinsop, Alexandra / Monod, Mélodie / van Sighem, Ard / Pantazis, Nikos / Bezemer, Daniela / Op de Coul, Eline / van de Laar, Thijs / Fraser, Christophe / Prins, Maria / Reiss, Peter / de Bree, Godelieve J / Ratmann, Oliver

    eLife

    2022  Volume 11

    Abstract: Background: More than 300 cities including the city of Amsterdam in the Netherlands have joined the UNAIDS Fast-Track Cities initiative, committing to accelerate their HIV response and end the AIDS epidemic in cities by 2030. To support this commitment, ...

    Abstract Background: More than 300 cities including the city of Amsterdam in the Netherlands have joined the UNAIDS Fast-Track Cities initiative, committing to accelerate their HIV response and end the AIDS epidemic in cities by 2030. To support this commitment, we aimed to estimate the number and proportion of Amsterdam HIV infections that originated within the city, from Amsterdam residents. We also aimed to estimate the proportion of recent HIV infections during the 5-year period 2014-2018 in Amsterdam that remained undiagnosed.
    Methods: We located diagnosed HIV infections in Amsterdam using postcode data (PC4) at time of registration in the ATHENA observational HIV cohort, and used HIV sequence data to reconstruct phylogeographically distinct, partially observed Amsterdam transmission chains. Individual-level infection times were estimated from biomarker data, and used to date the phylogenetically observed transmission chains as well as to estimate undiagnosed proportions among recent infections. A Bayesian Negative Binomial branching process model was used to estimate the number, size, and growth of the unobserved Amsterdam transmission chains from the partially observed phylogenetic data.
    Results: Between 1 January 2014 and 1 May 2019, there were 846 HIV diagnoses in Amsterdam residents, of whom 516 (61%) were estimated to have been infected in 2014-2018. The rate of new Amsterdam diagnoses since 2014 (104 per 100,000) remained higher than the national rates excluding Amsterdam (24 per 100,000), and in this sense Amsterdam remained a HIV hotspot in the Netherlands. An estimated 14% [12-16%] of infections in Amsterdan MSM in 2014-2018 remained undiagnosed by 1 May 2019, and 41% [35-48%] in Amsterdam heterosexuals, with variation by region of birth. An estimated 67% [60-74%] of Amsterdam MSM infections in 2014-2018 had an Amsterdam resident as source, and 56% [41-70%] in Amsterdam heterosexuals, with heterogeneity by region of birth. Of the locally acquired infections, an estimated 43% [37-49%] were in foreign-born MSM, 41% [35-47%] in Dutch-born MSM, 10% [6-18%] in foreign-born heterosexuals, and 5% [2-9%] in Dutch-born heterosexuals. We estimate the majority of Amsterdam MSM infections in 2014-2018 originated in transmission chains that pre-existed by 2014.
    Conclusions: This combined phylogenetic, epidemiologic, and modelling analysis in the UNAIDS Fast-Track City Amsterdam indicates that there remains considerable potential to prevent HIV infections among Amsterdam residents through city-level interventions. The burden of locally acquired infection remains concentrated in MSM, and both Dutch-born and foreign-born MSM would likely benefit most from intensified city-level interventions.
    Funding: This study received funding as part of the H-TEAM initiative from Aidsfonds (project number P29701). The H-TEAM initiative is being supported by Aidsfonds (grant number: 2013169, P29701, P60803), Stichting Amsterdam Dinner Foundation, Bristol-Myers Squibb International Corp. (study number: AI424-541), Gilead Sciences Europe Ltd (grant number: PA-HIV-PREP-16-0024), Gilead Sciences (protocol numbers: CO-NL-276-4222, CO-US-276-1712, CO-NL-985-6195), and M.A.C AIDS Fund.
    MeSH term(s) Acquired Immunodeficiency Syndrome/epidemiology ; Bayes Theorem ; Cities/epidemiology ; HIV Infections/diagnosis ; HIV Infections/epidemiology ; HIV Infections/prevention & control ; Homosexuality, Male ; Humans ; Male ; Phylogeny
    Language English
    Publishing date 2022-08-03
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.76487
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Book ; Online: Bayesian mixture models for phylogenetic source attribution from consensus sequences and time since infection estimates

    Blenkinsop, Alexandra / Sofocleous, Lysandros / di Lauro, Francesco / Kostaki, Evangelia Georgia / van Sighem, Ard / Bezemer, Daniela / van de Laar, Thijs / Reiss, Peter / de Bree, Godelieve / Pantazis, Nikos / Ratmann, Oliver

    2023  

    Abstract: In stopping the spread of infectious diseases, pathogen genomic data can be used to reconstruct transmission events and characterize population-level sources of infection. Most approaches for identifying transmission pairs do not account for the time ... ...

    Abstract In stopping the spread of infectious diseases, pathogen genomic data can be used to reconstruct transmission events and characterize population-level sources of infection. Most approaches for identifying transmission pairs do not account for the time that passed since divergence of pathogen variants in individuals, which is problematic in viruses with high within-host evolutionary rates. This is prompting us to consider possible transmission pairs in terms of phylogenetic data and additional estimates of time since infection derived from clinical biomarkers. We develop Bayesian mixture models with an evolutionary clock as signal component and additional mixed effects or covariate random functions describing the mixing weights to classify potential pairs into likely and unlikely transmission pairs. We demonstrate that although sources cannot be identified at the individual level with certainty, even with the additional data on time elapsed, inferences into the population-level sources of transmission are possible, and more accurate than using only phylogenetic data without time since infection estimates. We apply the approach to estimate age-specific sources of HIV infection in Amsterdam MSM transmission networks between 2010-2021. This study demonstrates that infection time estimates provide informative data to characterize transmission sources, and shows how phylogenetic source attribution can then be done with multi-dimensional mixture models.
    Keywords Quantitative Biology - Populations and Evolution ; Statistics - Methodology
    Subject code 310
    Publishing date 2023-04-13
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Global, regional, and national minimum estimates of children affected by COVID-19-associated orphanhood and caregiver death, by age and family circumstance up to Oct 31, 2021: an updated modelling study.

    Unwin, H Juliette T / Hillis, Susan / Cluver, Lucie / Flaxman, Seth / Goldman, Philip S / Butchart, Alexander / Bachman, Gretchen / Rawlings, Laura / Donnelly, Christl A / Ratmann, Oliver / Green, Phil / Nelson, Charles A / Blenkinsop, Alexandra / Bhatt, Samir / Desmond, Chris / Villaveces, Andrés / Sherr, Lorraine

    The Lancet. Child & adolescent health

    2022  Volume 6, Issue 4, Page(s) 249–259

    Abstract: Background: In the 6 months following our estimates from March 1, 2020, to April 30, 2021, the proliferation of new coronavirus variants, updated mortality data, and disparities in vaccine access increased the amount of children experiencing COVID-19- ... ...

    Abstract Background: In the 6 months following our estimates from March 1, 2020, to April 30, 2021, the proliferation of new coronavirus variants, updated mortality data, and disparities in vaccine access increased the amount of children experiencing COVID-19-associated orphanhood. To inform responses, we aimed to model the increases in numbers of children affected by COVID-19-associated orphanhood and caregiver death, as well as the cumulative orphanhood age-group distribution and circumstance (maternal or paternal orphanhood).
    Methods: We used updated excess mortality and fertility data to model increases in minimum estimates of COVID-19-associated orphanhood and caregiver deaths from our original study period of March 1, 2020-April 30, 2021, to include the new period of May 1-Oct 31, 2021, for 21 countries. Orphanhood was defined as the death of one or both parents; primary caregiver loss included parental death or the death of one or both custodial grandparents; and secondary caregiver loss included co-residing grandparents or kin. We used logistic regression and further incorporated a fixed effect for western European countries into our previous model to avoid over-predicting caregiver loss in that region. For the entire 20-month period, we grouped children by age (0-4 years, 5-9 years, and 10-17 years) and maternal or paternal orphanhood, using fertility contributions, and we modelled global and regional extrapolations of numbers of orphans. 95% credible intervals (CrIs) are given for all estimates.
    Findings: The number of children affected by COVID-19-associated orphanhood and caregiver death is estimated to have increased by 90·0% (95% CrI 89·7-90·4) from April 30 to Oct 31, 2021, from 2 737 300 (95% CrI 1 976 100-2 987 000) to 5 200 300 (3 619 400-5 731 400). Between March 1, 2020, and Oct 31, 2021, 491 300 (95% CrI 485 100-497 900) children aged 0-4 years, 736 800 (726 900-746 500) children aged 5-9 years, and 2 146 700 (2 120 900-2 174 200) children aged 10-17 years are estimated to have experienced COVID-19-associated orphanhood. Globally, 76·5% (95% CrI 76·3-76·7) of children were paternal orphans, whereas 23·5% (23·3-23·7) were maternal orphans. In each age group and region, the prevalence of paternal orphanhood exceeded that of maternal orphanhood.
    Interpretation: Our findings show that numbers of children affected by COVID-19-associated orphanhood and caregiver death almost doubled in 6 months compared with the amount after the first 14 months of the pandemic. Over the entire 20-month period, 5·0 million COVID-19 deaths meant that 5·2 million children lost a parent or caregiver. Our data on children's ages and circumstances should support pandemic response planning for children globally.
    Funding: UK Research and Innovation (Global Challenges Research Fund, Engineering and Physical Sciences Research Council, and Medical Research Council), Oak Foundation, UK National Institute for Health Research, US National Institutes of Health, and Imperial College London.
    MeSH term(s) Adolescent ; Adult ; COVID-19/mortality ; Caregivers/supply & distribution ; Child ; Child, Orphaned/statistics & numerical data ; Female ; Humans ; Male ; Models, Statistical
    Language English
    Publishing date 2022-02-25
    Publishing country England
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ISSN 2352-4650
    ISSN (online) 2352-4650
    DOI 10.1016/S2352-4642(22)00005-0
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Many but small HIV-1 non-B transmission chains in the Netherlands.

    Bezemer, Daniela / Blenkinsop, Alexandra / Hall, Matthew / van Sighem, Ard / Cornelissen, Marion / Wessels, Els / van Kampen, Jeroen / van de Laar, Thijs / Reiss, Peter / Fraser, Christophe / Ratmann, Oliver

    AIDS (London, England)

    2021  Volume 36, Issue 1, Page(s) 83–94

    Abstract: Objective: The aim of this study was to investigate introductions and spread of different HIV-1 subtypes in the Netherlands.: Design: We identified distinct HIV-1 transmission chains in the Netherlands within the global epidemic context through viral ...

    Abstract Objective: The aim of this study was to investigate introductions and spread of different HIV-1 subtypes in the Netherlands.
    Design: We identified distinct HIV-1 transmission chains in the Netherlands within the global epidemic context through viral phylogenetic analysis of partial HIV-1 polymerase sequences from individuals enrolled in the ATHENA national HIV cohort of all persons in care since 1996, and publicly available international background sequences.
    Methods: Viral lineages circulating in the Netherlands were identified through maximum parsimony phylogeographic analysis. The proportion of HIV-1 infections acquired in-country among heterosexuals and MSM was estimated from phylogenetically observed, national transmission chains using a branching process model that accounts for incomplete sampling.
    Results: As of 1 January 2019, 2589 (24%) of 10 971 (41%) HIV-1 sequenced individuals in ATHENA had non-B subtypes (A1, C, D, F, G) or circulating recombinant forms (CRF01AE, CRF02AG, CRF06-cpx). The 1588 heterosexuals were in 1224, and 536 MSM in 270 phylogenetically observed transmission chains. After adjustments for incomplete sampling, most heterosexual (75%) and MSM (76%) transmission chains were estimated to include only the individual introducing the virus (size = 1). Onward transmission occurred mostly in chains size 2-5 amongst heterosexuals (62%) and in chains size at least 10 amongst MSM (64%). Considering some chains originated in-country from other risk-groups, 40% (95% confidence interval: 36-44) of non-B-infected heterosexuals and 62% (95% confidence interval: 49-73) of MSM-acquired infection in-country.
    Conclusion: Although most HIV-1 non-B introductions showed no or very little onward transmission, a considerable proportion of non-B infections amongst both heterosexuals and MSM in the Netherlands have been acquired in-country.
    MeSH term(s) HIV Infections ; HIV-1/genetics ; Heterosexuality ; Homosexuality, Male ; Humans ; Male ; Netherlands/epidemiology ; Phylogeny
    Language English
    Publishing date 2021-09-29
    Publishing country England
    Document type Journal Article
    ZDB-ID 639076-6
    ISSN 1473-5571 ; 0269-9370 ; 1350-2840
    ISSN (online) 1473-5571
    ISSN 0269-9370 ; 1350-2840
    DOI 10.1097/QAD.0000000000003074
    Database MEDical Literature Analysis and Retrieval System OnLINE

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