Emerging Infectious Diseases (May 2021)

Herd Immunity against Severe Acute Respiratory Syndrome Coronavirus 2 Infection in 10 Communities, Qatar

  • Andrew Jeremijenko,
  • Hiam Chemaitelly,
  • Houssein H. Ayoub,
  • Moza Alishaq,
  • Abdul-Badi Abou-Samra,
  • Jameela Ali A.A. Al Ajmi,
  • Nasser Ali Asad Al Ansari,
  • Zaina Al Kanaani,
  • Abdullatif Al Khal,
  • Einas Al Kuwari,
  • Ahmed Al-Mohammed,
  • Naema Hassan Abdulla Al Molawi,
  • Huda Mohamad Al Naomi,
  • Adeel A. Butt,
  • Peter Coyle,
  • Reham Awni El Kahlout,
  • Imtiaz Gillani,
  • Anvar Hassan Kaleeckal,
  • Naseer Ahmad Masoodi,
  • Anil George Thomas,
  • Hanaa Nafady-Hego,
  • Ali Nizar Latif,
  • Riyazuddin Mohammad Shaik,
  • Nourah B.M. Younes,
  • Hanan F. Abdul Rahim,
  • Hadi M. Yassine,
  • Mohamed G. Al Kuwari,
  • Hamad Eid Al Romaihi,
  • Mohamed H. Al-Thani,
  • Roberto Bertollini,
  • Laith J. Abu-Raddad

DOI
https://doi.org/10.3201/eid2705.204365
Journal volume & issue
Vol. 27, no. 5
pp. 1343 – 1352

Abstract

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We investigated what proportion of the population acquired severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and whether the herd immunity threshold has been reached in 10 communities in Qatar. The study included 4,970 participants during June 21–September 9, 2020. Antibodies against SARS-CoV-2 were detected by using an electrochemiluminescence immunoassay. Seropositivity ranged from 54.9% (95% CI 50.2%–59.4%) to 83.8% (95% CI 79.1%–87.7%) across communities and showed a pooled mean of 66.1% (95% CI 61.5%–70.6%). A range of other epidemiologic measures indicated that active infection is rare, with limited if any sustainable infection transmission for clusters to occur. Only 5 infections were ever severe and 1 was critical in these young communities; infection severity rate of 0.2% (95% CI 0.1%–0.4%). Specific communities in Qatar have or nearly reached herd immunity for SARS-CoV-2 infection: 65%–70% of the population has been infected.

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