- 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.
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.
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.”
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.
When liquid meets gas, a unique zone forms. Variable by nature, molecules can cross from one state to another, combining in unique ways to either desirable or unwanted ends. From heat escaping a mug [...]
A newly detected coronavirus variant is on the rise in England, with the virus believed to be an offshoot of Delta. According to a briefing from the UK Health Security Agency, released on Friday, [...]
A team of researchers has developed a new nanomechanical technique for fast, one-step, immune-affinity tests, which can quantify the immune response induced by different COVID-19 variants in serum. Their technique provides a new tool [...]
Lawrence Livermore National Laboratory (LLNL) scientists have developed a new method for 3D printing living microbes in controlled patterns, expanding the potential for using engineered bacteria to recover rare-earth metals, clean wastewater, detect uranium, [...]
Nanomedicines may offer clinicians a way to deliver precise, targeted therapy directly to tumors without damaging surrounding tissue. Yet, progress in the development of new drugs that treat cancer at the nanoparticle level has [...]
Cambridge researchers have discovered how T cells—an important component of our immune system—are able keep on killing as they hunt down and kill cancer cells, repeatedly reloading their toxic weapons. Cytotoxic T [...]
Sunday, October 3, set records for the most COVID-19 deaths in Russia on a single day. Only 29% of people in Russia are vaccinated, despite the country being the first to approve a vaccine. [...]
New research from the University of Technology Sydney (UTS) has found that pathogens that form biofilms can evolve to survive nanosilver treatment. The study is the first to demonstrate that long-term nanosilver treatment can [...]
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, [...]
Freeze-dried genetic circuits could reveal the presence of SARS-CoV-2, Ebola, MRSA, and more. Masks and testing have been key to the COVID-19 pandemic response—and now devices that combine the two may be on the [...]
Hundreds of neuroscientists built a ‘parts list’ of the motor cortex, laying groundwork to map the whole brain and better understand brain diseases. Before you read any further, bring your hand to your forehead. [...]
An international team, led by Swinburne University of Technology and Australian National University (ANU), have made a breakthrough discovery that could potentially lead to faster, more accurate molecular or virus tests, including for COVID-19. [...]
New mutations of COVID-19, such as the Delta strain, are "getting better" at transmitting through the air, a study has found. People infected with a later variant of COVID-19 put 43 to 100 times more virus into [...]
Merck will seek U.S. approval for pill as soon as possible If approved, would be 1st oral antiviral COVID-19 drug Merck shares rally, some vaccine makers fall U.S. government to buy 1.7 mln courses [...]
An antiviral surface coating technology sprayed on face masks could provide an extra layer of protection against COVID-19 and the flu. The coating developed at The University of Queensland has already proven effective in killing [...]
Key Points Monash researchers have developed a method to prepare elongated nanocrystals to deliver therapeutic drugs Elongated nanocrystals can carry a high payload of drugs to potentially increase drug targetability and also decrease dosage [...]