Since South African scientists first spotted Omicron more than four months ago, many variants have evolved, including BA.2 currently available in Canada and around the world.  Here’s what we know so far about the XE sub-variant:


WHAT IS XE SIGNATURE? 
XE is a recombination of BA.1, which led Canada’s fifth wave during the winter break and all of January, and BA.2, which powers the current sixth wave.  There were 1,125 XE cases in the UK on April 5, representing less than one percent of the total sequences, according to a technical update issued by the UK Health Insurance Agency (UKHSA) on April 8.
In addition to the mutations from BA.1 and BA.2, XE also contains three mutations that are not present in all sequences for BA.1 and BA.2, according to the UK report.


HOW COMMON ARE THE RECOVERY VARIETIES? 
“Recombinant variants are not uncommon, especially when multiple variants are available,” said Dr. Susan Hopkins, UKHSA Chief Medical Advisor, in a statement on March 25.
“Several have been identified during the pandemic to date.  “As with other variants, most will die relatively quickly.”
The UK has previously identified other recombinants, including XD and XF, which are recombinant of Delta and Omicron BA.1.


HOW MUCH IS THE TRANSMISSION? 
The World Health Organization’s technical director, Dr. Maria Van Kerkhove, said in a brief video question and answer that XE appears to have about a 10 percent increase in transmissibility, based on early analysis of available sequences.  However, Van Kerkhove said that reports that described it as 10 times more contagious were incorrect.
The UK health agency said it had an average growth rate of 12.6 percent per week above BA.2, but noted that over the past three weeks, the growth rate has risen to 20.9 percent.
WHO ranks XE in Omicron, which is a variation of the concern.  The agency added that sub-variables and recombinant forms should be monitored as separate genealogies by public health authorities.
The Public Health Agency of Canada (PHAC) says it is actively monitoring variants of COVID-19 and evaluating new Omciron subcategories and recombinations such as XE.
“Scientists are looking for evidence that XE alters the severity of the disease, the contagion or the effectiveness of diagnostic tests, vaccines or treatments for COVID-19,” Mark Johnson told CTVNews.ca in an email on Thursday.
“While preliminary international reports have shown that XE has moderately increased transmissibility compared to BA.2, more data is needed to confirm this finding.”


WHERE WERE CASES OF IDENTIFIED? 
As of April 14, a case of subcategory XE, collected by border surveillance on March 22, 2022, has been confirmed in Canada, according to PHAC.
“PHAC had previously suspected five other possible XE scans.  “However, after further investigation, it was determined that it is not XE but is of undetermined origin given the ongoing improvements,” Johnson said.
“It should be noted that there are currently several COVID-19 recombinants monitored worldwide other than XE, which is not surprising given the overlap of the Delta and Omicron variants as well as the co-circulation of BA.1 and BA .2 subcategories. of Omicron.
In the United Kingdom, most cases have been reported in the East of England, London and the South East, according to a report by the British Health Agency, with the first case reported on 19 January.
XE cases have also been reported in India, Japan, among other countries, according to various media outlets.


DO VACCINES STILL WORK? 
While scientists are still learning more about XE and other subcategories, real-world research and data show that vaccines continue to provide protection against serious diseases, especially after a booster vaccine.
“We need to make sure that when it’s your turn to get vaccinated and get the full range of doses you need,” said WHO’s Van Kerkhove, especially those who are more vulnerable, the elderly, and those with underlying conditions.  workers.