Studies suggest Omicron has higher 'asymptomatic carriage'
Preliminary findings from two South African clinical trials suggest the Omicron coronavirus variant has a much higher rate of "asymptomatic carriage" than earlier variants, which could explain why it has spread so rapidly across the globe.
The studies - one of which was carried out when Omicron infections were surging in South Africa last month and another which resampled participants around the same time - found a far greater number of people tested positive for the coronavirus but were not showing symptoms compared to previous trials.
In the Ubuntu study evaluating the efficacy of Moderna's Covid-19 vaccine in people living with HIV, 31% of 230 participants undergoing screening tested positive, with all 56 samples available for sequencing analysis verified to be Omicron.
"This is in stark contrast to the positivity rate pre-Omicron, which ranged from less than 1% to 2.4%," the researchers said in a statement.
In a subgroup of the Sisonke trial evaluating the efficacy of Johnson & Johnson's Covid-19 vaccine, the mean asymptomatic carriage rate rose to 16% during the Omicron period from 2.6% during the Beta and Delta outbreaks.
"The Sisonke study included 577 subjects previously vaccinated, ... with results suggesting a high carriage rate even in those known to be vaccinated," the researchers said.
They added that the "higher asymptomatic carriage rate is likely a major factor in the rapid and widespread dissemination of the variant, even among populations with high prior rates of coronavirus infection".
South Africa experienced a surge in Covid-19 infections from late November, around the time its scientists alerted the world to Omicron. But new cases have since fallen back and early indications are that the wave has been marked by less serious disease than earlier ones.
Comments
Research Reports
Projects
Latest Multimedia
Latest News
Showroom
Education: Consulting with member companies to obtain the optimal benefits from their B-BBEE spending, skills resources as well as B-BBEE points
VISIT SHOWROOM
Weir Minerals Europe, Middle East and Africa is a global supplier of excellent minerals solutions, including pumps, valves, hydrocyclones,...
VISIT SHOWROOM
Press Office
Announcements
What's On
Subscribe to improve your user experience...
Option 1 (equivalent of R125 a month):
Receive a weekly copy of Creamer Media's Engineering News & Mining Weekly magazine
(print copy for those in South Africa and e-magazine for those outside of South Africa)
Receive daily email newsletters
Access to full search results
Access archive of magazine back copies
Access to Projects in Progress
Access to ONE Research Report of your choice in PDF format
Option 2 (equivalent of R375 a month):
All benefits from Option 1
PLUS
Access to Creamer Media's Research Channel Africa for ALL Research Reports, in PDF format, on various industrial and mining sectors
including Electricity; Water; Energy Transition; Hydrogen; Roads, Rail and Ports; Coal; Gold; Platinum; Battery Metals; etc.
Already a subscriber?
Forgotten your password?
Receive weekly copy of Creamer Media's Engineering News & Mining Weekly magazine (print copy for those in South Africa and e-magazine for those outside of South Africa)
➕
Recieve daily email newsletters
➕
Access to full search results
➕
Access archive of magazine back copies
➕
Access to Projects in Progress
➕
Access to ONE Research Report of your choice in PDF format
RESEARCH CHANNEL AFRICA
R4500 (equivalent of R375 a month)
SUBSCRIBEAll benefits from Option 1
➕
Access to Creamer Media's Research Channel Africa for ALL Research Reports on various industrial and mining sectors, in PDF format, including on:
Electricity
➕
Water
➕
Energy Transition
➕
Hydrogen
➕
Roads, Rail and Ports
➕
Coal
➕
Gold
➕
Platinum
➕
Battery Metals
➕
etc.
Receive all benefits from Option 1 or Option 2 delivered to numerous people at your company
➕
Multiple User names and Passwords for simultaneous log-ins
➕
Intranet integration access to all in your organisation
