Assessment of the Risk of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Reinfection in an Intense Reexposure Setting

  1. Laith J Abu-Raddad
  2. Hiam Chemaitelly
  3. Joel A Malek
  4. Ayeda A Ahmed
  5. Yasmin A Mohamoud
  6. Shameem Younuskunju
  7. Houssein H Ayoub
  8. Zaina Al Kanaani
  9. Abdullatif Al Khal
  10. Einas Al Kuwari
  11. Adeel A Butt
  12. Peter Coyle
  13. Andrew Jeremijenko
  14. Anvar Hassan Kaleeckal
  15. Ali Nizar Latif
  16. Riyazuddin Mohammad Shaik
  17. Hanan F Abdul Rahim
  18. Hadi M Yassine
  19. Mohamed G Al Kuwari
  20. Hamad Eid Al Romaihi
  21. Mohamed H Al-Thani
  22. Roberto Bertollini

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Abstract

Background

Risk of reinfection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is unknown. We assessed the risk and incidence rate of documented SARS-CoV-2 reinfection in a cohort of laboratory-confirmed cases in Qatar.

Methods

All SARS-CoV-2 laboratory-confirmed cases with at least 1 polymerase chain reaction–positive swab that was ≥45 days after a first positive swab were individually investigated for evidence of reinfection. Viral genome sequencing of the paired first positive and reinfection viral specimens was conducted to confirm reinfection.

Results

Out of 133 266 laboratory-confirmed SARS-CoV-2 cases, 243 persons (0.18%) had at least 1 subsequent positive swab ≥45 days after the first positive swab. Of these, 54 cases (22.2%) had strong or good evidence for reinfection. Median time between the first swab and reinfection swab was 64.5 days (range, 45–129). Twenty-three of the 54 cases (42.6%) were diagnosed at a health facility, suggesting presence of symptoms, while 31 (57.4%) were identified incidentally through random testing campaigns/surveys or contact tracing. Only 1 person was hospitalized at the time of reinfection but was discharged the next day. No deaths were recorded. Viral genome sequencing confirmed 4 reinfections of 12 cases with available genetic evidence. Reinfection risk was estimated at 0.02% (95% confidence interval [CI], .01%–.02%), and reinfection incidence rate was 0.36 (95% CI, .28–.47) per 10 000 person-weeks.

Conclusions

SARS-CoV-2 reinfection can occur but is a rare phenomenon suggestive of protective immunity against reinfection that lasts for at least a few months post primary infection.

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  1. ScreenIT

    SciScore for 10.1101/2020.08.24.20179457: (What is this?)

    Please note, not all rigor criteria are appropriate for all manuscripts.

    Table 1: Rigor

    Institutional Review Board StatementIRB: Ethical approval: The study was approved by HMC and Weill Cornell Medicine-Qatar Institutional Review Boards.
    Randomizationnot detected.
    Blindingnot detected.
    Power Analysisnot detected.
    Sex as a biological variablenot detected.

    Table 2: Resources

    Antibodies
    SentencesResources
    , an electrochemiluminescence immunoassay that uses a recombinant protein representing the nucleocapsid (N) antigen for the determination of antibodies against SARS-CoV-2.
    SARS-CoV-2
    suggested: None
    Software and Algorithms
    SentencesResources
    Raw sequences were processed with CUTADAPT (v2.10) [17] to exclude the contaminating adapter sequences.
    CUTADAPT
    suggested: (cutadapt, RRID:SCR_011841)
    The latter filtered reads were aligned to SARS-CoV-2 reference genome (NC_045512) using BWA-MEM [18].
    BWA-MEM
    suggested: (Sniffles, RRID:SCR_017619)
    Variant calling and genotyping were performed with VarScan multi-sample mpileup [19] with the pileup file generated using SAMTOOLS mpileup (v1.10) [20] with --min-BQ 20 and --min-MQ 20 parameters.
    VarScan
    suggested: (VARSCAN, RRID:SCR_006849)
    SAMTOOLS
    suggested: (SAMTOOLS, RRID:SCR_002105)

    Results from OddPub: We did not detect open data. We also did not detect open code. Researchers are encouraged to share open data when possible (see Nature blog).

    Results from LimitationRecognizer: We detected the following sentences addressing limitations in the study:
    This assessment has limitations. We assessed risk of only documented reinfections, but other reinfections could have occurred but went undocumented, perhaps because of minimal or no symptoms. It is possible that with the primed immune system following the primary infection, reinfections are milder and shorter and thus less likely to be documented [10], though still can be infectious as the Ct value was quite low, indicating high viral load, in some of the reinfections. Viral genome sequencing analysis was possible for only a subset of reinfections. Antibody testing outcomes were available for only a number of cases, limiting use and inferences of the link between antibody status and risk of reinfection. Of note that for one of the genetically-confirmed reinfections the antibody test result was available but was sero-negative, just as the Hong Kong reinfected patient [23]. In conclusion, SARS-CoV-2 reinfection appears to be a rare phenomenon. This suggests that immunity develops after the primary infection and lasts for at least a few months, and that immunity protects against reinfection.

    Results from TrialIdentifier: No clinical trial numbers were referenced.

    Results from Barzooka: We did not find any issues relating to the usage of bar graphs.

    Results from JetFighter: We did not find any issues relating to colormaps.

    Results from rtransparent:
    • Thank you for including a conflict of interest statement. Authors are encouraged to include this statement when submitting to a journal.
    • Thank you for including a funding statement. Authors are encouraged to include this statement when submitting to a journal.
    • No protocol registration statement was detected.

    About SciScore

    SciScore is an automated tool that is designed to assist expert reviewers by finding and presenting formulaic information scattered throughout a paper in a standard, easy to digest format. SciScore checks for the presence and correctness of RRIDs (research resource identifiers), and for rigor criteria such as sex and investigator blinding. For details on the theoretical underpinning of rigor criteria and the tools shown here, including references cited, please follow this link.

  2. Version published to 10.1093/cid/ciaa1846
  3. Version published to 10.1101/2020.08.24.20179457v2 on medRxiv
  4. Version published to 10.1101/2020.08.24.20179457v1 on medRxiv