- New variants of SARS-CoV-2 are more virulent and transmissible than the original variant of the virus.
- Health experts associate these variants of concern (VOCs) with increased risk of hospitalization, intensive care unit (ICU) admission, and death.
- Vaccination reduces the risks of severe disease and death even with the VOCs.
- However, even with increased vaccination, control measures are needed to reduce the spread of the VOCs.
A Canadian study has found a link between the new variants of SARS-CoV-2, particularly the Delta variant, and an increased risk of severe disease and death.
The retrospective study, by the University of Toronto and appearing in the Canadian Medical Association Journal (CMAJ), looked at 212,326 cases in Ontario from February 7 to June 27, 2021. The study authors compared the risks of hospitalization, ICU admission, and death from the VOCs with those risks from non-VOC SARS-CoV-2 strains.
The researchers screened the cases for Alpha, Beta, Gamma, and Delta VOCs. Non-VOC infections made up 22.4% of the cases. More than three-quarters of the cases were Alpha, Beta, or Gamma, while 2.8% were probably Delta.
Alpha, Beta, and Gamma variants have a mutation that increasesTrusted Source transmission, while Delta has a mutation that increases its ability to replicate.
The authors note that before May 2021, there was no routine screening for the Delta variant, so it is likely that the numbers underestimate the prevalence of this variant.
Increased risk from the Delta variant
The present study found that all VOCs increased people’s risk of hospitalization, ICU admission, and death due to COVID-19.
However, the highest risks were from the Delta variant. In the Delta cases, there was a 108% increase in the risk of hospitalization, a 235% increased risk of ICU admission, and a 133% higher risk of death, compared with the original variant.
These effects were present even when the researchers adjusted the data for factors such as age, sex, vaccination status, and comorbidities.
Prof. William Schaffner, infectious diseases specialist at the Vanderbilt University Medical Center in Nashville, TN, commented:
“This important study from Canada reinforces the serious impact the Delta variant is having. It is well recognized that Delta is more contagious than other virus variants. This new study convincingly reinforces the finding that it also causes more severe disease.”
The Delta variant is now the dominant variant in the European Union, the United Kingdom, and the United States.
The findings of the present study corroborate those of the studies in EnglandTrusted Source, ScotlandTrusted Source, and Singapore that have also shown increased risks from the Delta variant.
Speaking to Medical News Today, Dr. Christopher Coleman, assistant professor of infection immunology at the University of Nottingham in the U.K., highlighted the international relevance of the study.
He said, “Although this [Canadian] study has some limitations, as acknowledged by the authors, this is exactly the kind of study that helps ‘build a picture’ by showing that similar observations can be observed in a lot of different circumstances.”
“It is not something unique about the U.K. that means the Delta variant is associated with more dangerous infections only here,” he added.
News
Does COVID increase the risk of Alzheimer’s disease?
Scientists discover that even mild COVID-19 can alter brain proteins linked to Alzheimer’s disease, potentially increasing dementia risk—raising urgent public health concerns. A recent study published in the journal Nature Medicine investigated whether both mild and [...]
New MRI Study Reveals How Cannabis Alters Brain Activity and Weakens Memory
A massive new study sheds light on how cannabis affects the brain, particularly during cognitive tasks. Researchers analyzed over 1,000 young adults and found that both heavy lifetime use and recent cannabis consumption significantly reduced brain [...]
How to Assess Nanotoxicity: Key Methods and Protocols
With their high surface area and enhanced physicochemical properties, nanomaterials play a critical role in drug delivery, consumer products, and environmental technologies. However, their nanoscale dimensions enable interactions with cellular components in complex and [...]
Nanotech drug delivery shows lasting benefits, reducing need for repeat surgeries
A nanotechnology-based drug delivery system developed at UVA Health to save patients from repeated surgeries has proved to have unexpectedly long-lasting benefits in lab tests – a promising sign for its potential to help human patients. [...]
Scientists Just Found DNA’s Building Blocks in Asteroid Bennu – Could This Explain Life’s Origins?
Japanese scientists detected all five nucleobases — building blocks of DNA and RNA — in samples returned from asteroid Bennu by NASA’s OSIRIS-REx mission. NASA’s OSIRIS-REx mission brought back 121.6 grams of asteroid Bennu, unveiling nitrogen-rich organic matter, including DNA’s essential [...]
AI-Designed Proteins – Unlike Any Found in Nature – Revolutionize Snakebite Treatment
Scientists have pioneered a groundbreaking method to combat snake venom using newly designed proteins, offering hope for more effective, accessible, and affordable antivenom solutions. By utilizing advanced computational techniques and deep learning, this innovative [...]
New nanosystem offers hope for improved diagnosis and treatment of tongue cancer
A pioneering study has unveiled the Au-HN-1 nanosystem, a cutting-edge approach that promises to transform the diagnosis and treatment of tongue squamous cell carcinoma (TSCC). By harnessing gold nanoparticles coupled with the HN-1 peptide, [...]
Global Trust in Science Is Stronger Than Expected – What’s Next?
A landmark global survey conducted across 68 countries has found that public trust in scientists remains robust, with significant support for their active involvement in societal and political matters. The study highlights the public’s [...]
Microplastics in the bloodstream may pose hidden risks to brain health
In a recent study published in the journal Science Advances, researchers investigated the impact of microplastics on blood flow and neurobehavioral functions in mice. Using advanced imaging techniques, they observed that microplastics obstruct cerebral blood [...]
AI Surveillance: New Study Exposes Hidden Risks to Your Privacy
A new mathematical model enhances the evaluation of AI identification risks, offering a scalable solution to balance technological benefits with privacy protection. AI tools are increasingly used to track and monitor people both online [...]
Permafrost Thaw: Unleashing Ancient Pathogens and Greenhouse Gases
Permafrost is a fascinating yet alarming natural phenomenon. It refers to ground that remains frozen for at least two consecutive years. Mostly found in polar regions like Siberia, Alaska, and Canada, permafrost plays a [...]
Frequent social media use tied to higher levels of irritability
A survey led by researchers from the Center for Quantitative Health at Massachusetts General Hospital and Harvard Medical School has analyzed the association between self-reported social media use and irritability among US adults. Frequent [...]
Australian oysters’ blood could hold key to fighting drug-resistant superbugs
Protein found in Sydney rock oysters’ haemolymph can kill bacteria and boost some antibiotics’ effectiveness, scientists discover An antimicrobial protein found in the blood of an Australian oyster could help in the fight against [...]
First U.S. H5N1 Death Sparks Urgency: Scientists Warn Bird Flu Is Mutating Faster Than Expected
A human strain of H5N1 bird flu isolated in Texas shows mutations enabling better replication in human cells and causing more severe disease in mice compared to a bovine strain. While the virus isn’t [...]
AI Breakthrough in Nanotechnology Shatters Limits of Precision
At TU Graz, a pioneering research group is leveraging artificial intelligence to drastically enhance the way nanostructures are constructed. They aim to develop a self-learning AI system that can autonomously position molecules with unprecedented precision, potentially [...]
How Missing Sleep Lets Bad Memories Haunt Your Mind
Research reveals that a lack of sleep can hinder the brain’s ability to suppress unwanted memories and intrusive thoughts, emphasizing the importance of restful sleep for mental health. Sleep deprivation has been found to [...]
