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BA.4 and BA.5 Omicron: How worried should we be? | |
(3 months later) | |
Two new fast-spreading subvariants of Omicron are causing fresh surges of Covid around the world. | |
BA.4 and BA.5 were first identified in South Africa and may soon become the dominant strains in Europe and the US, health experts say. | |
What exactly are BA.4 and BA.5? | |
Ever since it first emerged, Covid has been mutating or shape-shifting. The new genetic versions that keep appearing are called variants. | |
There have been a few major variants already, such as alpha and delta, that have caused massive waves of infection. | |
The latest ones experts are concerned about - BA.4 and BA.5 - are very closely related to the Omicron variant behind last winter's wave. | |
They were added to the World Health Organization's monitoring list in March and have also been designated as variants of concern in Europe. | |
Where are they spreading? | |
They were spotted circulating in South Africa at the beginning of the year and now appear to be spreading much more quickly than other variants. | |
Most European countries now have them and they look set to overtake other types of Covid soon. That's already happened in Portugal - BA.5 is now dominant there. | |
In the US, officials say they are seeing rising numbers of infections caused by the two new subvariants. | |
Covid infections in the UK are also showing early signs of a possible rise, driven by BA.4 and BA.5. | |
Australia has reported cases too. | |
Will they be harmful? | |
Experts are unsure how hard countries will be hit. | |
BA.4 and BA.5 Omicron are not thought to be any more lethal than other types of Covid. | |
Lots of people have built up some immunity from past infections and vaccination, which is helping to make the disease less risky overall. | |
But the new subvariants do appear to be spreading more easily. | |
This is partly because immunity may be waning, but also because of the mutations the virus has undergone. | |
Many countries have also lifted their Covid restrictions, meaning people are mixing more, which gives the virus more chances to spread. | |
BA.4 and BA.5 appear to be able to infect people even if they've recently had other types of Omicron. | |
A wave of new infections could lead to more hospitalisations and some more deaths. | |
How can we protect against them? | |
As with other Covid variants, the risk or serious illness remains highest for people who are elderly, or who have significant underlying health conditions. | |
Although current vaccines are not a perfect fit, they are still the best line of defence. | |
They have cut the risk of severe illness against the other major Covid variants, including Delta, Alpha, Beta and Gamma. | They have cut the risk of severe illness against the other major Covid variants, including Delta, Alpha, Beta and Gamma. |
Doctors say it is vital people get the recommended number of doses to gain maximum protection against existing and emerging variants. | Doctors say it is vital people get the recommended number of doses to gain maximum protection against existing and emerging variants. |
Extra Covid booster in spring for over-75s and high risk | Extra Covid booster in spring for over-75s and high risk |
How many people have been vaccinated so far? | How many people have been vaccinated so far? |
How quickly could we get new vaccines against variants? | How quickly could we get new vaccines against variants? |
Updated versions of vaccines against Covid variants are already being designed and tested. | Updated versions of vaccines against Covid variants are already being designed and tested. |
Manufacturers could scale up production quickly too, and regulators have already discussed how to fast-track the approval process. | Manufacturers could scale up production quickly too, and regulators have already discussed how to fast-track the approval process. |
Why do variants occur? | Why do variants occur? |
Viruses make carbon copies of themselves to reproduce, but they aren't perfect at it. Errors creep in that change the genetic blueprint, resulting in a new version of the virus. | Viruses make carbon copies of themselves to reproduce, but they aren't perfect at it. Errors creep in that change the genetic blueprint, resulting in a new version of the virus. |
If this gives the virus a survival advantage, the new version will thrive. | If this gives the virus a survival advantage, the new version will thrive. |
The more chances coronavirus has to make copies of itself in us - the host - the more opportunities there are for mutations to occur. | The more chances coronavirus has to make copies of itself in us - the host - the more opportunities there are for mutations to occur. |