A new strain of COVID-19 dubbed the Kraken variant is spreading rapidly across the world and health officials have released a list of 12 symptoms that may signal infection.
With a remarkable ability to evade immune responses previously established by vaccines or previous COVID-19 infections, Kraken has quickly begun to take hold in the US.
Kraken made up 27.7 percent of sequenced COVID-19 cases in the US last week. However, in the northeastern US, it made up more than 70 percent.
"It is widely anticipated to go up in frequency globally, and may cause a sizeable fraction of cases globally in the near future," said University College London Genetics Institute director Professor Francois Balloux.
It's understood that China's ending of its zero-COVID policy, which has led to a spike in infections, is creating a perfect environment for mutations to occur.
Kraken, or XBB.1.5, is a descendant of the Omicron XBB subvariant. It is a recombinant of BA.2.10.1 and BA.2.75 sublineages and The World Health Organization (WHO) has labelled the strain "the most transmissible sub-variant that has been detected yet".
The variant was originally identified in October 2022 and has now been detected in 29 countries, including eight cases in Australia over the holiday period.
It is yet to be detected in New Zealand but it is expected to only be a matter of time.
Kraken appears to have the ability to bind to cells while evading the body's immune defences, leading to greatly increased transmissibility, according to Professor Wendy Barclay from Imperial College London.
The cold-like symptoms that Kraken produces are largely the same as Omicron, and, according to the UK's National Health Service, can include:
- A high temperature or shivering - your chest or back will feel hot to the touch (there is no need to measure your temperature)
- A new, continuous cough - this may look like coughing a lot for over an hour or three plus coughing episodes in a day
- Shortness of breath
- Changes to, or loss of, sense of smell and taste
- Feelings of fatigue or exhaustion
- A sore throat
- Aches throughout your body
- Headaches
- A blocked or runny nose
- Loss of appetite
- Feeling or being sick
- Diarrhoea
People experiencing any of these symptoms are recommended to take a rapid antigen test.
Professor Andrew Pollard, Oxford Vaccine Group director, has urged calm in the reaction to Kraken.
"There is no reason to think that XBB.1.5 is of any more concern than other variants that come and go in the ever-changing landscape of COVID-19 mutants," he said.
This is backed up by other experts who do not expect the Kraken variant to cause more severe disease than other COVID-19 lineages.