Two Omicron subvariants are fast-spreading and causing new surges in Covid all over the globe.
Health experts believe that BA.4 (and BA.5) were the first strains to be identified in South Africa. They could soon be the dominant strains in Europe, the US and Asia.
Since its inception, Covid has been evolving or changing shape. Variants are the new genetic forms that keep popping up.
There have been several major variants of the virus, including alpha and delta. These have already caused huge waves of infection.
Experts are most concerned about BA.4 (the latest) and BA.5 (the latest). These are closely related to Omicron variants that were behind the wave last winter.
They were added to World Health Organization's monitoring lists in March.
They were first spotted in South Africa at beginning of the year. Now, they appear to be spreading faster than any other varieties.
They are now common in Europe and will soon overtake other types. This has already been seen in Portugal, where BA.5 is the dominant type.
Officials in the USA claim that they are witnessing an increase in infections due to the two subvariants.
Covid infections are on the rise in the UK, driven by BA.4 & BA.5.
Australia also reported cases.
Experts aren't sure how difficult countries will be hit.
BA.4 Omicron and BA.5 Omicron do not appear to be more deadly than other types.
Many people have developed immunity to past infections and vaccinations, which makes the disease less dangerous overall.
However, the subvariants are spreading faster.
This could be partly due to waning immunity, but also because the virus has gone through mutations.
Many countries have also removed their Covid restrictions. This means that people are mixing more which increases the chances of the virus spreading.
BA.4/BA.5 seem to be capable of infecting people, even if they have had Omicron before.
An epidemic of new infections could result in more hospitalisations or even more deaths.
As with all Covid variants of the drug, people over 65 or with significant underlying medical conditions are at greater risk for serious illness.
Even though current vaccines may not be the best, they are still the best line for defense.
They have reduced the risk of serious illness in comparison to the other major Covid variants like Delta, Alpha and Beta, as well as Gamma.
Doctors recommend that people take the recommended doses in order to be protected against new and existing variants.
Current versions of vaccines against Covid variants have been tested and are being developed.
Manufacturers could increase production quickly, and regulators already discuss how to speed up the approval process.
Although viruses make carbon copies of their own DNA to reproduce, they are not perfect at it. There are errors that can occur, which alter the genetic blueprint and result in a new virus version.
The virus will survive if this happens, and the new version of the virus will flourish.
The higher the chance that coronavirus will make copies of itself within us, the host, the greater the chances for mutations.
