
At least 1 in 3 people infected with COVID-19 never develop symptoms, according to new analysis Findings suggest COVID-19 testing should be expanded to those without symptoms who may be unknowingly spreading the virus.
January 22, 2021
LA JOLLA, CA A new data analysis including more than 1.8 million people confirms that asymptomatic infections of the SARS-CoV-2 virus are a major portion of COVID-19's global footprint, representing at least a third of cases.
The findings, published today in Annals of Internal Medicine, build on the authors' prior review of more limited data sets in June 2020, which also found that a significant proportion of SARS-CoV-2 infections did not produce symptoms.
In the new report, Scripps Research's Eric Topol, MD, and Daniel Oran once again dig into the data, this time reviewing a much larger set of 61 studies and reports from around the world including two massive serosurveys in England and Spain that tested the presence of SARS-CoV-2 antibodies in hundreds of thousands of people. In both of those studies, about one-third of the individuals were shown to have had the virus but never experienced symptoms.
The biggest implication of this is that we need to test far more widely and frequently, and not confined to people with symptoms, says Topol, founder and director of the Scripps Research Translational Institute and professor of Molecular Medicine at Scripps Research. We need to urgently get rapid home antigen tests to every household for daily use.
Inexpensive, at-home testing would also help identify those who are presymptomatic, which means they have not yet developed symptoms. About half of all new infections are believed to be caused by people who are either presymptomatic or asymptomatic.
Another implication of our review is that we need to figure out how effective vaccines are in preventing asymptomatic infection, says Oran, a member of the digital medicine group at Scripps Research Translational Institute. Early data are encouraging, but we still have a lot more to learn.
The authors note that it was just about one year ago on January 24, 2020 that the first asymptomatic case of COVID-19 was documented, but largely ignored.
Now we know with certainty that asymptomatic infection is a notable feature of SARS-CoV-2 , Topol says. It's time that we translate this knowledge into smarter testing practices that will help to bring COVID-19 under control.
Video: Eric Topol and Danny Oran discuss asymptomatic COVID-19
COVID-19 Translational Medicine Topol, Eric
Most recent headlines
09/11/2025
Dalet today announced a transformative leap forward for media operations: Agentic Artificial Intelligence (AI) that unifies the Dalet ecosystem under one natura...
05/11/2025
College Hoops Preview 2025: ESPN Remote-Ops Team Preps for Massive Slate of Men&...
05/11/2025
University of Iowa Centralizes Video Production With Dual Control Rooms at Carve...
05/11/2025
On Monday night, Ed Sheeran and Spotify lit up The Royal Dublin Society in Dublin for a one-night-only performance. The occasion? The third installment of Billi...
05/11/2025
Cumbia has long been woven into daily life in Argentina, and its popularity on S...
05/11/2025
La cumbia forma parte del d a a d a de los argentinos desde siempre, y su popula...
05/11/2025
Earlier this year, our in-house publishing imprint, Spotify Audiobooks, put out ...
05/11/2025
SBS showcases next generation of pro cyclists in extended broadcast deal with Pr...
05/11/2025
Photo credit: CIVMEC...
05/11/2025
A Nielsen survey of 500 directors and millions of monday.com workflows reveals t...
05/11/2025
Prime Video's VoD offerings included for the first time in standardized AGF Measurement
Frankfurt, October 28, 2025. AGF Videoforschung, together with Ama...
05/11/2025
A 13-year old company that serves as a master control/disaster recovery hub for PBS stations says it has seen little financial impact from cuts to public broadc...
05/11/2025
To no one's surprise, the NFL's most dominant franchise in recent years attracts the most TV viewers, according to new research by S&P Global Markete In...
05/11/2025
MELBOURNE, Australia Atomos today introduced Ninja TX GO, a new HDMI monitor-recorder that combines a brighter screen, advanced monitoring tools, professional c...
05/11/2025
WASHINGTON Despite the ongoing government shutdown, Federal Communications Commission Chairman Brendan Carr has announced a tentative agenda for the agency'...
05/11/2025
The College Football Playoff (CFP), ESPN and TNT Sports have announced kick times and broadcast information for the 2025 CFP First Round, which will launch the ...
05/11/2025
NEW YORK IAB Tech Lab, the global digital advertising technical standards-setting body, has announced the release of device attestation support in the industry ...
05/11/2025
SINGAPORE Appear, an Oslo-based provider of live production technology, is opening a new facility in Singapore as part of the company's expansion into the A...
05/11/2025
DALLAS Parks Associates has released new data showing just how far the dramatic shift to streaming services has gone in recent years. Currently, more than nine ...
05/11/2025
Supports existing services while powering 16 new products for government and ent...
05/11/2025
Wednesday 5 November 2025
To view this content, please enable our use of cookie...
05/11/2025
Wednesday 5 November 2025
To view this content, please enable our use of cookie...
05/11/2025
Rohde & Schwarz Mobile Test Summit 2025 on the future of wireless communications...
05/11/2025
Wuppertal November 5, 2025
Riedel RefCam and Easy5G to Make Handball Debut at the Men's EHF EURO 2026The European Handball Federation (EHF) will introduce...
05/11/2025
Back to All News
Netflix's Third Season of Ads and a Look Ahead at Whats Next
Amy Reinhard
President, Advertising
Business
05 November 2025
United Sta...
05/11/2025
Comscore and Polaris I/O Partner to Automate Audience Insights in MarketView for...
05/11/2025
New schedule will be live on-air Monday 10 November
Brand-new Today with David McCullagh from 9am
Oliver Callan in all-new extended show from 11am to 1pm
Kie...
05/11/2025
Explore the future with Science Week on RT
Dive into a week of innovative, themed programming and content across RT television, radio and online
Includes a ...
05/11/2025
Get ready for six weeks of United FC, a brand-new, feel-good teen docuseries kic...
04/11/2025
SVG Sit-Down: Why Professional Fight League CEO John Martin Believes Growth Is I...
04/11/2025
SVG All-Stars: David Koppett, Executive Producer, Live Sports and Studio, NESN a...
04/11/2025
From concept to kick-off: How TAMS could transform sports workflows By Paul Markham
Tuesday, October 28, 2025 - 09:43
Print This Story
Techex tx darwin pr...
04/11/2025
College Hoops Preview 2025: The CW Tips Off Third Season of ACC Men's/Women&...
04/11/2025
College Hoops Preview 2025: Big Ten Network Heats Up for Busy Season With 500 Me...
04/11/2025
College Hoops Preview 2025: CBS Sports Readies 300+ Game Broadcasts Across Its P...
04/11/2025
College Hoops Preview 2025: NBC Sports Slate Features 200+ Big Ten, BIG EAST, an...
04/11/2025
College Hoops Preview 2025: ESPN Remote-Ops Team Preps for Massive Slate of 7,40...
04/11/2025
Never-before-seen footage of Selena Quintanilla and her family's band offers...
04/11/2025
Joel Edgerton at Train Dreams Park City premiere (photo by Soul Brother / Shutterstock for Sundance Film Festival)...
04/11/2025
Today, we announced our third quarter 2025 earnings, marking strong momentum as we surpassed 700 million Monthly Active Users and achieved double-digit subscrib...
04/11/2025
Idag rapporterar vi v rt resultat f r det tredje kvartalet 2025, vilket markerar en stark och fortsatt tillv xt d vi passerade 700 miljoner m natliga aktiva an...
04/11/2025
SBS calls for bold, thought-provoking factual ideas: up to $50,000 in developmen...
04/11/2025
Tomorrow's fight will demand networks that deliver both capacity and survivability, the speed to move mission applications at scale, and the resilience to e...
04/11/2025
New York, NY - November 3, 2025 - Neptune BidCo US Inc. (the Issuer or the Co...
04/11/2025
WASHINGTON The National Association of Broadcasters took aim at YouTube TV and its owner Google in a blog post for its heavy hand in deciding what viewers can ...
04/11/2025
HACKENSACK, N.J. The European Broadcasting Union (EBU) has awarded LiveU a five-year contract to deliver 24/7 live news content through its Eurovision News Exch...
04/11/2025
Bob Dylan Awarded Honorary Doctorate from Berklee College of Music The songwriter, performer, and cultural icon is recognized for a six-decade career that redef...
04/11/2025
SAN JOSE, Calif. Roku has launched Roku Ads API, a fully open, self-serve developer platform for connected TV (CTV) advertising. The Roku Ads API gives develope...
04/11/2025
Harmonic (NASDAQ: HLIT) today announced an expanded partnership with Spectrum to extend the company's industry-leading cOS vCMTS and advanced network and o...
04/11/2025
The inauguration of Empresa de Meios Audiovisuais' (EMAV's) first virtual studio in Lisbon marks a major technological milestone for the Portuguese audi...