• Duration of mRNA vaccine protection against SARS-CoV-2 Omicron BA.1 and BA.2 subvariants in Qatar. 

      Chemaitelly, Hiam; Ayoub, Houssein H; AlMukdad, Sawsan; Coyle, Peter; Tang, Patrick; ... more authors ( Nature Research , 2022 , Article)
      SARS-CoV-2 Omicron BA.1 and BA.2 subvariants are genetically divergent. We conducted a matched, test-negative, case-control study to estimate duration of protection of the second and third/booster doses of mRNA COVID-19 ...
    • 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 ...
    • Hepatitis C virus infection spontaneous clearance: Has it been underestimated? 

      Ayoub H.H.; Chemaitelly H.; Omori R.; Abu-Raddad L.J. ( Elsevier B.V. , 2018 , Article)
      Objectives: Hepatitis C virus (HCV) clearance rate (fclearance) is defined as the proportion of infected persons who will spontaneously clear their infection after acute infection. We aimed to estimate fclearance using a ...
    • Is hypertension a predictor for heart failure? A cross cultural comparison over a 10-year period 

      Bener, A.; Al Suwaidi, J.; Ghaffar, A. ( Elsevier B.V. , 2005 , Article)
      This was a retrospective cohort study to assess the effect of hypertension (HTN) among Qatari and Asian patients admitted to the Hamad General Hospital in Qatar with heart failure (HF) and to identify risk factors that ...
    • 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 ...
    • 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 ...
    • 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 of Omicron sub-lineage infection against reinfection with another Omicron sub-lineage 

      Chemaitelly, Hiam; Ayoub, Houssein H.; Coyle, Peter; Tang, Patrick; Yassine, Hadi M.; ... more authors ( Nature Research , 2022 , Article)
      There is significant genetic distance between SARS-CoV-2 Omicron (B.1.1.529) variant BA.1 and BA.2 sub-lineages. This study investigates immune protection of infection with one sub-lineage against reinfection with the other ...
    • SARS-CoV-2 antibody-positivity protects against reinfection for at least seven months with 95% efficacy 

      Laith J., Abu-Raddad; Chemaitelly, Hiam; Coyle, Peter; Malek, Joel A.; Ahmed, Ayeda A.; ... more authors ( Elsevier , 2021 , Article)
      Background Reinfection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been documented, raising public health concerns. SARS-CoV-2 reinfections were assessed in a cohort of antibody-positive persons ...