Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Copy numbers of viral RNA in swab‐soaked samples for four types of SARS‐CoV‐2 variant cases, estimated by reverse transcription‐quantitative PCR. Cases are marked according to the severity (upper panel) and the generation (lower panel). PCR, polymerase chain reaction; SARS‐CoV‐2, severe acute respiratory syndrome coronavirus 2
