Browsing Mathematics, Statistics & Physics by Subject "COVID-19"

Now showing items 1-20 of 21

    • Association of Serum Vitamin D level and COVID-19 infection: A Case-control Study 

      AlYafei, Najat Abdrabbo; Jaleel, Bushra Naaz Fathima; Abdel-Salam, Abdel-Salam G.; Al-Saadi, Hamda Ali; Al Abdulla, Samya Ahmad ( HBKU Press , 2022 , Article)
      Background: Vitamin D is considered a potent modulator of the immune system, albeit its role in COVID-19 infection is a matter of debate. The present study aimed to estimate the association between serum vitamin D levels ...

    • BNT162b2 and mRNA-1273 COVID-19 vaccine effectiveness against the SARS-CoV-2 Delta variant in Qatar. 

      Tang, Patrick; Hasan, Mohammad R; Chemaitelly, Hiam; Yassine, Hadi M; Benslimane, Fatiha M; ... more authors ( Nature Researc , 2021 , Article)
      With the global expansion of the highly transmissible SARS-CoV-2 Delta (B.1.617.2) variant, we conducted a matched test-negative case-control study to assess the real-world effectiveness of COVID-19 messenger RNA vaccines ...

    • BNT162b2 antigen dose and SARS-CoV-2 omicron infection in adolescents 

      Chemaitelly, Hiam; Ayoub, Houssein H.; Coyle, Peter; Tang, Patrick; Yassine, Hadi M.; ... more authors ( Elsevier , 2023 , Other)
      COVID-19 vaccine antigen dose might affect protection against SARS-CoV-2 infection,1, 2 but direct evidence to quantify this effect is absent. We conducted a matched, retrospective, cohort study using a regression ...

    • Characterizing the effective reproduction number during the COVID-19 pandemic: Insights from Qatar’s experience 

      Bsat, Raghid; Chemaitelly, Hiam; Coyle, Peter; Tang, Patrick; Hasan, Mohammad R; ... more authors ( International Society of Global Health , 2022 , Article)
      Background: The effective reproduction number, Rt, is a tool to track and understand epidemic dynamics. This investigation of Rt estimations was conducted to guide the national COVID-19 response in Qatar, from the onset ...

    • Duration of immune protection of SARS-CoV-2 natural infection against reinfection. 

      Chemaitelly, Hiam; Nagelkerke, Nico; Ayoub, Houssein H; Coyle, Peter; Tang, Patrick; ... more authors ( Oxford University Press , 2022 , Article)
      The future of the SARS-CoV-2 pandemic hinges on virus evolution and duration of immune protection of natural infection against reinfection. We investigated duration of protection afforded by natural infection, the effect ...

    • 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 ...

    • 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 ...

    • Evaluating the Online Learning Experience at Higher Education Institutions 

      Abdel-Salam, Abdel Salam G.; Hazaa, Khalifa; Abu-Shanab, Emad Ahmed ( IGI Global , 2022 , Article)
      In light of recent COVID-19 pandemic, universities had to cope by resorting to online learning without previous preparation. This paper tries to investigate student satisfaction with online learning. The literature review ...

    • Herd immunity against severe acute respiratory syndrome coronavirus 2 infection in 10 communities, qatar 

      Jeremijenko, A.; Chemaitelly, H.; Ayoub, H.H.; Alishaq, M.; Abou-Samra, A.-B.; ... more authors ( Centers for Disease Control and Prevention (CDC) , 2021 , Article)
      We investigated what proportion of the population acquired severe acute respiratory syndrome coronavirus 2 (SARSCoV- 2) infection and whether the herd immunity threshold has been reached in 10 communities in Qatar. The ...

    • Impact of COVID-19 Pandemic News on the Cryptocurrency Market and Gold Returns: A Quantile-on-Quantile Regression Analysis 

      Mahdi, Esam; Al-Abdulla, Ameena ( MDPI , 2022 , Article)
      In this paper, we investigate the relationship between the RavenPack news-based index associated with coronavirus outbreak (Panic, Sentiment, Infodemic, and Media Coverage) and returns of two commodities—Bitcoin and gold. ...

    • Long-term COVID-19 booster effectiveness by infection history and clinical vulnerability and immune imprinting: a retrospective population-based cohort study 

      Hiam, Chemaitelly; Ayoub, Houssein H; Tang, Patrick; Coyle, Peter; Yassine, Hadi M; ... more authors ( Elsevier , 2023 , Article)
      BackgroundLong-term effectiveness of COVID-19 mRNA boosters in populations with different previous infection histories and clinical vulnerability profiles is inadequately understood. We aimed to investigate the effectiveness ...

    • 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 ...

    • Monitoring SEIRD model parameters using MEWMA for the COVID-19 pandemic with application to the state of Qatar 

      Boone, Edward L.; Abdel-Salam, Abdel Salam G.; Sahoo, Indranil; Ghanam, Ryad; Chen, Xi; ... more authors ( Taylor and Francis Group , 2021 , Article)
      During the current COVID-19 pandemic, decision-makers are tasked with implementing and evaluating strategies for both treatment and disease prevention. In order to make effective decisions, they need to simultaneously ...

    • 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 ...

    • Protection from previous natural infection compared with mRNA vaccination against SARS-CoV-2 infection and severe COVID-19 in Qatar: a retrospective cohort study 

      Hiam, Chemaitelly; Ayoub, Houssein H; AlMukdad, Sawsan; Coyle, Peter; Tang, Patrick; ... more authors ( Elsevier , 2022 , Article)
      BackgroundUnderstanding protection conferred by natural SARS-CoV-2 infection versus COVID-19 vaccination is important for informing vaccine mandate decisions. We compared protection conferred by natural infection versus ...

    • Relative infectiousness of SARS-CoV-2 vaccine breakthrough infections, reinfections, and primary infections. 

      Abu-Raddad, Laith J; Chemaitelly, Hiam; Ayoub, Houssein H; Tang, Patrick; Coyle, Peter; ... more authors ( Springer , 2022 , Article)
      SARS-CoV-2 breakthrough infections in vaccinated individuals and in those who had a prior infection have been observed globally, but the transmission potential of these infections is unknown. The RT-qPCR cycle threshold ...