Abstract
WHO convened an Advisory Group (AG) to consider the feasibility, potential value, and limitations of establishing a closely-monitored challenge model of experimental severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and coronavirus disease 2019 (COVID-19) in healthy adult volunteers. The AG included experts in design, establishment, and performance of challenges. This report summarizes issues that render a COVID-19 model daunting to establish (the potential of SARS-CoV-2 to cause severe/fatal illness, its high transmissibility, and lack of a "rescue treatment"to prevent progression from mild/moderate to severe clinical illness) and it proffers prudent strategies for stepwise model development, challenge virus selection, guidelines for manufacturing challenge doses, and ways to contain SARS-CoV-2 and prevent transmission to household/community contacts. A COVID-19 model could demonstrate protection against virus shedding and/or illness induced by prior SARS-CoV-2 challenge or vaccination. A limitation of the model is that vaccine efficacy in experimentally challenged healthy young adults cannot per se be extrapolated to predict efficacy in elderly/high-risk adults.
Original language | English (US) |
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Pages (from-to) | 2035-2041 |
Number of pages | 7 |
Journal | Clinical Infectious Diseases |
Volume | 72 |
Issue number | 11 |
DOIs | |
State | Published - Jun 1 2021 |
Keywords
- COVID-19
- SARS-CoV-2
- adult volunteers
- challenge model
- experimental challenge
ASJC Scopus subject areas
- Microbiology (medical)
- Infectious Diseases