While existing vaccination can still reduce the risk of severe Covid disease, the variants can evade many of the neutralising antibodies that are the immune system's front line of defence.
According to WHO, the SARS-CoV-2 virus continues to evolve. With such intense transmission worldwide, further variants, including recombinants, will emerge. This is expected."
Both BA.4 and BA.5 have also been added to the UK agency's monitoring list. One case each of BA.4 has already been detected in Scotland and England, up to March 30, according to the UKHSA.
The new sub-variant, designated as Omicron BA.4 and BA.5 has already been detected in three other countries and on four people in Botswana.
It forms clusters as it successfully spreads to people, and this gets noticed during genome sequencing. Only these successful sublineages make news which are given names like XD, XE etc.
Current knowledge also indicates that wildlife does not play a significant role in the spread of SARS-CoV-2 in humans, but spread in animal populations can affect the health of these populations and may facilitate the emergence of new virus variants.
Unless virus circulation is reduced, the world's vast gene pool will become the lab for variant mutation. Africa continent is vulnerable. Fully vaccinated are also susceptible, says WHO
The virus uses the spike protein to latch on to and enter the cells it infects. The Omicron spike protein has 37 mutations that distinguish it from the first SARS-CoV-2 isolates in 2020.
Although Alpha, Beta, Delta, and Omicron variants showed a slight increase in ethanol resistance in response to increased environmental stability, all VOCs on the skin surface were completely inactivated by 15 second exposure to 35 per cent ethanol.
"Know your risk tolerance. Get boosted, wear a KN/N95 mask. If COVID still gets you, you'll likely fully recover," he added.
The strain is also known as the 'IHU' variant because it was first identified by academics at the IHU Mediterranee Infection institute in Marseille, France
"It's not clear in India, where mainly people have had two doses plus an infection, whether this will be adequate. There will be certain people who are vulnerable who get sick and do need ventilation, especially the unvaccinated. That's why caution is needed and focus on infection transmission interruption and vaccination are so important."
Meanwhile, WHO on Tuesday also stated that emerging evidence reveals that the Omicron is affecting the upper respiratory tract, causing milder symptoms than previous variants.
"Last two years of experience shows that we can fight Covid with mask and the Covid appropriate behaviour... we will fight this variant too."
Research from an Imperial College London study and Scottish paper Early Pandemic Evaluation and Enhanced Surveillance of Covid-19, states that people with Omicron are 15 to 20 per cent less likely to need hospital treatment.