Browsing by Author "Chemaitelly, Hiam"

Now showing items 21-40 of 57

    • Effectiveness of the BNT162b2 Covid-19 Vaccine against the B.1.1.7 and B.1.351 Variants. 

      Abu-Raddad, Laith J; Chemaitelly, Hiam; Butt, Adeel A ( Massachusetts Medical Society , 2021 , Other)
      The messenger RNA vaccine BNT162b2 (Pfizer–BioNTech) has 95% efficacy against coronavirus disease 2019 (Covid-19). Qatar launched a mass immunization campaign with this vaccine on December 21, 2020. As of March 31, 2021, ...

    • Effectiveness of the neutralizing antibody sotrovimab among high-risk patients with mild-to-moderate SARS-CoV-2 in Qatar 

      Ahmed, Zaqout; Almaslamani, Muna A.; Chemaitelly, Hiam; Hashim, Samar A.; Ittaman, Ajithkumar; ... more authors ( Elsevier , 2022 , Article)
      ObjectivesTo estimate the real-world effectiveness of sotrovimab against severe, critical, or fatal COVID-19 in Qatar at a time in which most SARS-CoV-2 incidences occurred due to the BA.2 Omicron subvariant. MethodsWe ...

    • Effects of BA.1/BA.2 subvariant, vaccination, and prior infection on infectiousness of SARS-CoV-2 omicron infections. 

      Qassim, Suelen H; Chemaitelly, Hiam; Ayoub, Houssein H; AlMukdad, Sawsan; Tang, Patrick; ... more authors ( Oxford University Press , 2022 , Article)
      Compared to BA.1, BA.2 was associated with lower RT-qPCR cycle threshold (Ct) value-3.53 fewer cycles (95% CI: 3.46-3.60), signifying higher infectiousness. This may reflect higher viral load and/or longer duration of ...

    • Effects of Previous Infection and Vaccination on Symptomatic Omicron Infections. 

      Altarawneh, Heba N; Chemaitelly, Hiam; Ayoub, Houssein H; Tang, Patrick; Hasan, Mohammad R; ... more authors ( Massachusetts Medical Society , 2022 , Article)
      The protection conferred by natural immunity, vaccination, and both against symptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with the BA.1 or BA.2 sublineages of the omicron (B.1.1.529) ...

    • Effects of previous infection, vaccination, and hybrid immunity against symptomatic Alpha, Beta, and Delta SARS-CoV-2 infections: an observational study 

      Heba N., Altarawneh; Chemaitelly, Hiam; Ayoub, Houssein H.; Tang, Patrick; Hasan, Mohammad R.; ... more authors ( Elsevier , 2023 , Article)
      BackgroundProtection against SARS-CoV-2 symptomatic infection and severe COVID-19 of previous infection, mRNA two-dose vaccination, mRNA three-dose vaccination, and hybrid immunity of previous infection and vaccination ...

    • Effects of SARS-CoV-2 Alpha, Beta, and Delta variants, age, vaccination, and prior infection on infectiousness of SARS-CoV-2 infections 

      Qassim, Suelen H.; Hasan, Mohammad R.; Tang, Patrick; Chemaitelly, Hiam; Ayoub, Houssein H.; ... more authors ( Frontiers Media , 2022 , Article)
      In 2021, Qatar experienced considerable incidence of SARS-CoV-2 infection that was dominated sequentially by the Alpha, Beta, and Delta variants. Using the cycle threshold (Ct) value of an RT-qPCR-positive test to proxy ...

    • Epidemiological impact of prioritising SARS-CoV-2 vaccination by antibody status: Mathematical modelling analyses 

      Ayoub, H.H.; Ayoub, Houssein H.; Chemaitelly, Hiam; Makhoul, Monia; Al Kanaani, Zaina; ... more authors ( BMJ Publishing Group , 2021 , Article)
      Background Vaccines against SARS-CoV-2 have been developed, but their availability falls far short of global needs. This study aimed to investigate the impact of prioritising available doses on the basis of recipient ...

    • Estimates of global SARS-CoV-2 infection exposure, infection morbidity, and infection mortality rates in 2020 

      Houssein H., Ayoub; Mumtaz, Ghina R.; Seedat, Shaheen; Makhoul, Monia; Chemaitelly, Hiam; ... more authors ( Elsevier , 2021 , Article)
      We aimed to estimate, albeit crudely and provisionally, national, regional, and global proportions of respective populations that have been infected with SARS-CoV-2 in the first year after the introduction of this virus ...

    • Estimating protection afforded by prior infection in preventing reinfection: Applying the test-negative study design. 

      Ayoub, Houssein H; Tomy, Milan; Chemaitelly, Hiam; Altarawneh, Heba N; Coyle, Peter; ... more authors ( Oxford University Press , 2023 , Article)
      The COVID-19 pandemic has highlighted the need to use infection testing databases to rapidly estimate effectiveness of prior infection in preventing reinfection ($P{E}_S$) by novel SARS-CoV-2 variants. Mathematical modeling ...

    • First characterisation of antimicrobial susceptibility and resistance of Neisseria gonorrhoeae isolates in Qatar, 2017-2020 

      Al-Maslamani, Muna; Elmagboul, Emad Bashier Ibrahim; Puthiyottil, Aslam; Chemaitelly, Hiam; Varghese, Manoj Kizhakkepeedikayil; ... more authors ( Public Library of Science , 2022 , Article)
      Limited data are available regarding antimicrobial resistance in Neisseria gonorrhoeae strains circulating in WHO Eastern Mediterranean Region (EMR). We investigated the antimicrobial susceptibility/resistance of N. ...

    • Global epidemiology of Neisseria gonorrhoeae in infertile populations: Systematic review, meta-analysis and metaregression 

      Chemaitelly, Hiam; Majed, Alzahraa; Abu-Hijleh, Farah; Blondeel, Karel; Matsaseng, Thabo Christopher; ... more authors ( BMJ Journals , 2021 , Article)
      Objective To provide an in-depth systematic assessment of the global epidemiology of gonorrhoea infection in infertile populations. Methods A systematic literature review was conducted up to 29 April 2019 on international ...

    • History of primary-series and booster vaccination and protection against Omicron reinfection 

      Chemaitelly, Hiam; Ayoub, Houssein H.; Tang, Patrick; Coyle, Peter V.; Yassine, Hadi M.; ... more authors ( American Association for the Advancement of Science , 2023 , Article)
      Laboratory evidence suggests a possibility of immune imprinting for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We investigated the differences in the incidence of SARS-CoV-2 reinfection in a ...

    • HIV incidence and impact of interventions among female sex workers and their clients in the Middle East and north Africa: a modelling study 

      Chemaitelly, Hiam; Ayoub, Houssein H.; Omori, Ryosuke; El Feki, Shereen; Hermez, Joumana G.; ... more authors ( Elsevier , 2022 , Article)
      Background: The incidence of HIV infection among female sex workers and their clients in the Middle East and north Africa is not well known. We aimed to assess HIV incidence, the contribution of heterosexual sex work ...

    • Immune Imprinting and Protection against Repeat Reinfection with SARS-CoV-2 

      Chemaitelly, Hiam; Ayoub, Houssein H.; Tang, Patrick; Hasan, Mohammad R.; Coyle, Peter; ... more authors ( Massachusetts Medical Society , 2022 , Other)
      More than 2 years into the coronavirus disease 2019 (Covid-19) pandemic, the global population carries heterogeneous immune histories derived from various exposures to infection, viral variants, and vaccination.1 Evidence ...

    • Introduction and expansion of the SARS-CoV-2 B.1.1.7 variant and reinfections in Qatar: A nationally representative cohort study 

      J. Abu-Raddad, Laith; Chemaitelly, Hiam; H. Ayoub, Houssein; Coyle, Peter; A. Malek, Joel; ... more authors ( Public Library of Science , 2021 , Article)
      Background The epidemiology of the SARS-CoV-2 B.1.1.7 (or Alpha) variant is insufficiently understood. This study’s objective was to describe the introduction and expansion of this variant in Qatar and to estimate the ...

    • Mathematical modeling of the SARSCoV-2 epidemic in Qatar and its impact on the national response to COVID-19 

      Ayoub, Houssein H.; Chemaitelly, Hiam; Seedat, Shaheen; Makhoul, Monia; Kanaani, Zaina Al; ... more authors ( University of Edinburgh , 2021 , Article)
      Background Mathematical modeling constitutes an important tool for planning robust responses to epidemics. This study was conducted to guide the Qatari national response to the severe acute respiratory syndrome coronavirus ...

    • Modeling the population-level impact of treatment on COVID-19 disease and SARS-CoV-2 transmission 

      Monia, Makhoul; Abu-Hijleh, Farah; Ayoub, Houssein H.; Seedat, Shaheen; Chemaitelly, Hiam; ... more authors ( Elsevier , 2022 , Article)
      Different COVID-19 treatment candidates are under development, and some are becoming available including two promising drugs from Merck and Pfizer. This study provides conceptual frameworks for the effects of three types ...

    • mRNA-1273 COVID-19 vaccine effectiveness against the B.1.1.7 and B.1.351 variants and severe COVID-19 disease in Qatar 

      Chemaitelly, Hiam; Yassine, Hadi M.; Benslimane, Fatiha M.; Al Khatib, Hebah A.; Tang, Patrick; ... more authors (2021 , Article)
      The SARS-CoV-2 pandemic continues to be a global health concern. The mRNA-1273 (Moderna) vaccine was reported to have an efficacy of 94.1% at preventing symptomatic COVID-19 due to infection with ‘wild-type’ variants in a ...

    • Pfizer-BioNTech mRNA BNT162b2 Covid-19 vaccine protection against variants of concern after one versus two doses. 

      Abu-Raddad, Laith J; Chemaitelly, Hiam; Yassine, Hadi M; Benslimane, Fatiha M; Al Khatib, Hebah A; ... more authors ( Oxford University Press , 2021 , Article)
      Strategies for rolling out vaccination against Coronavirus Disease 2019 (Covid-19) varied across countries. A key question is whether delaying administration of the second vaccine dose to vaccinate the largest number of ...

    • Population immunity of natural infection, primary-series vaccination, and booster vaccination in Qatar during the COVID-19 pandemic: an observational study 

      Suelen H., Qassim; Chemaitelly, Hiam; Ayoub, Houssein H.; Coyle, Peter; Tang, Patrick; ... more authors ( Elsevier , 2023 , Article)
      BackgroundWaning of natural infection protection and vaccine protection highlight the need to evaluate changes in population immunity over time. Population immunity of previous SARS-CoV-2 infection or of COVID-19 vaccination ...