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What are the Delta, Gamma, Beta and Alpha Covid variants? What are the Covid variants and will vaccines still work?
(30 days later)
Officials are keeping a close watch on a new descendent of the Delta variant of Covid, which is causing a growing number of infections in the UK. A new heavily mutated version of coronavirus has been found that scientists say is of "great concern".
AY.4.2 - which some are calling "Delta plus"- has changes or mutations that might potentially help the virus survive more effectively. One of most pressing questions is will vaccines still work?
What is the Delta variant and the new mutations? What is this new variant?
There are thousands of different types, or variants, of Covid circulating across the world. One of them, known as Delta or B.1.617.2, first identified in India, appears to be spreading quickly in many countries. There are thousands of different types, or variants, of Covid circulating across the world. That's to be expected because viruses mutate all the time.
Delta has become the dominant variant in the UK, where it is considered a "variant of concern" - meaning health officials watch it closely. But this new variant, called B.1.1.529 or Omicron, has experts particularly worried because it is very different to the original Covid, which current vaccines were designed to fight.
In July 2021 experts identified a new relative called AY.4.2. It has a long list of genetic changes - 50 in all. Of these, 32 are in the spike protein of the virus - the part which is the target of vaccines.
This Delta offshoot has been increasing slowly since then. It includes some new mutations affecting the spike protein, which the virus uses to penetrate our cells. However, it is too soon to know how much of a threat it poses.
So far, there's no indication that it's significantly more transmissible as a result of these changes, but experts are studying it closely. What do we know about this new variant?
It's not yet been categorised as a variant of concern, or a variant under investigation. Will vaccines still work?
Experts say it's unlikely to take off in a big way or defeat the current vaccines. Current vaccines are not an ideal match so might not work quite as well, say experts.
Other current variants of concern include: But that doesn't mean they'll offer zero protection.
Remember, vaccines are still very effective at protecting lives by cutting the risk of severe illness against 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.
In the UK, booster jabs are being offered to:
Over-40s
Frontline health and social care workers
Older adults in residential care homes
People aged 16-49 years old with underlying health conditions which put them at greater risk of severe Covid
Adults who share a household with vulnerable people
More than 16m booster or third doses have been given so far in the UK.
Although Covid infections have been rising again across the UK, the number of hospitalisations and deaths has remained well below the levels seen in earlier waves. Experts say this is because of the success of the vaccine programme.
Scientists will be running lots of tests to check if the vaccines will hold up against this latest variant.
It is early days, but experts will study potentially important mutations that might make it more infectious and able to sidestep some of the protection given by vaccines.
And they will assess if it is causing more serious disease than other variants.
How many people have been vaccinated so far?
How quickly could we get new vaccines against variants?
Updated versions of vaccines against Covid variants are already being designed and tested, in case they are needed at some point.
Should that time arrive, a new vaccine could be ready within weeks, to run checks on.
Manufacturers could scale up production quickly too and regulators have already discussed how to fast track the approval process.
No corners would be cut, but the whole process - from design to approval - could be much faster than when Covid vaccines were first launched.
What about the other variants?
Officials have a close watch on a few.
The most potentially dangerous ones are called variants of concern and include:
Delta (B.1.617.2), first identified in India and now the most common type circulating in the UK
Alpha (B.1.1.7), first identified in the UK but which spread to more than 50 countriesAlpha (B.1.1.7), first identified in the UK but which spread to more than 50 countries
Beta (B.1.351), first identified in South Africa but which has been detected in at least 20 other countries, including the UKBeta (B.1.351), first identified in South Africa but which has been detected in at least 20 other countries, including the UK
Gamma (P.1), first identified in Brazil but which has spread to more than 10 other countries, including the UKGamma (P.1), first identified in Brazil but which has spread to more than 10 other countries, including the UK
Viruses mutate all the time and most changes are inconsequential. Some even harm the virus. But others can make the disease more infectious or threatening - and these mutations tend to dominate. UK officials are also keeping an eye on a recent descendent of the Delta variant, called AY.4.2 or "Delta plus".
Is Delta more dangerous? How dangerous are variants?
There is no evidence that Delta, AY.4.2 - or any of the other variants - cause more serious illness for the vast majority of people. There is no evidence that any of them cause more serious illness for the vast majority of people.
As with the original version, the risk remains highest for people who are elderly or have significant underlying health conditions. As with original Covid, the risk remains highest for people who are elderly or have significant underlying health conditions.
But even so, if a variant is more infectious it will lead to more deaths in an unvaccinated population.But even so, if a variant is more infectious it will lead to more deaths in an unvaccinated population.
Vaccines offer high protection against severe illness with Covid-19, including infections caused by variants of concern. The shots also reduce the risk of infection. But they do not completely eliminate all risk.Vaccines offer high protection against severe illness with Covid-19, including infections caused by variants of concern. The shots also reduce the risk of infection. But they do not completely eliminate all risk.
The advice to avoid infection remains the same for all strains: wash your hands, keep your distance, wear a face covering in crowded places and be vigilant about ventilation.The advice to avoid infection remains the same for all strains: wash your hands, keep your distance, wear a face covering in crowded places and be vigilant about ventilation.
How many cases are there in the UK?How many cases are there in the UK?
Why has the Delta variant spread so quickly in UK?Why has the Delta variant spread so quickly in UK?
How are the mutants behaving? Why are variants occurring?
The variants of concern have all undergone changes to their spike protein - the part of the virus which attaches to human cells. Viruses make carbon copies of themselves to reproduce but they aren't perfect at it. Errors can creep in that change the genetic blueprint, resulting in a new version or variant.
Delta has some potentially important ones (such as L452R) that might make it spread more easily. If this gives the virus a survival advantage, the new version will thrive.
One mutation, called N501Y, shared by the Alpha, Gamma and Beta, seems to make the virus better at infecting cells and spreading. The more chances coronavirus has to make copies of itself in us - the host - the more opportunities there are for mutations to occur.
Beta and Gamma also have a key mutation, called E484K, that may help the virus sidestep some of the body's immune defences. That's why keeping infections down is important. Vaccines help by cutting transmission as well as protecting against serious Covid illness.
Experts have found a small number of cases of Alpha with this change too. Experts say it is possible that the new highly altered variant B.1.1.529 may have originated in a patient whose immune system was unable to get rid of a Covid infection quickly, giving the virus more time to morph.
Will vaccines still work against variants?
Current vaccines were designed for earlier versions of coronavirus, which means they may not be the ideal match for new variants and so might not work quite as well.
But experts say they are still very effective at protecting lives by cutting the risk of severe illness:
An analysis by Public Health England found two doses of either the Pfizer or AstraZeneca vaccine was more than 90% effective against hospitalisations for Covid-19 caused by Delta
However, a single dose was less effective at preventing illness from Delta, compared to how well it worked against Alpha
Doctors say it is vital that people get the recommended number of doses to gain maximum protection against existing and emerging variants.
Across the UK, additional booster jabs are being offered to:
Over-50s
Frontline health and social care workers
Older adults in residential care homes
People aged 16-49 years old with underlying health conditions which put them at greater risk of severe Covid
Adults who share a household with vulnerable people
Latest data from the NHS shows 3.7 million people in England have had a booster jab.
Although Covid infections have been rising again across the UK, the number of hospitalisations and deaths has remained well below the levels seen in earlier waves, which experts attribute to the success of the vaccine programme.
Is the pace of the Covid booster rollout too slow?
How many people have been vaccinated so far?