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A significant new subvariant of the coronavirus known as XBB.1.5 \u00ad\u2013 or \u2018the Kraken\u2019 \u2013 could soon cause a major upsurge in UK case numbers.<\/p>\n
The highly transmissible XBB.1.5 subvariant \u00ad\u2013 another offshoot of the Omicron<\/a> SARS-CoV-2 virus variant \u2013 has been detected in 38 countries so far, including the United Kingdom.<\/p>\n Although the United States is currently the hotspot for the sub-variant (XBB.1.5 accounting for an estimated half of the country\u2019s coronavirus cases<\/a>), the European Centre for Disease Prevention and Control (ECDC) predicts it will become the dominant form of coronavirus in Europe between February and March this year<\/a>.<\/p>\n So far, just less than a tenth of the world\u2019s XBB.1.5 cases have been identified in the UK<\/a>. But many scientists, such as Prof Paul Hunter<\/a>\u00a0from the Norwich Medical School of the University of East Anglia, claim a large wave of COVID cases is imminent.<\/p>\n \u201cAll the signs are that this is going to cause a bigger wave than we saw in the summer of 2022,\u201d he tells BBC Science Focus<\/em>. \u201cWhile infections are falling in the UK at the moment, I will expect that to reverse over the next few weeks.<\/p>\n Dr Jeremy Rossman<\/a>, senior lecturer in virology at the University of Kent, adds: \u201cA lot of scientists are concerned that we\u2019re at a really high risk of another relatively severe wave. We just haven\u2019t seen this jump in transmissibility in quite a while.\u201d<\/p>\n Read the latest COVID-19 news:<\/strong><\/p>\n Fortunately, there\u2019s no evidence so far that XBB.1.5 can cause more serious disease than its processors. Yet some serious questions remain. Could the Kraken\u2019s high transmissibility still cause a significant number of deaths? Why is it that XBB.1.5 can spread more easily? And will vaccines still work against it? We examine all below.<\/p>\n First identified in October 2022, XBB.1.5 is a new sub-variant of the globally dominant Omicron coronavirus variant.<\/p>\n To get a bit more technical, it\u2019s a mix of other significant Omicron sub-variants. As signified by the X in its name, XBB.1.5 (and its ancestor XBB) came about through a recombination of sub-variants BA.2.10.1 and BA.2.75.<\/p>\n Now, it\u2019s not just the mix of these previous sub-variants that makes XBB.1.5 such a problem \u2013 there are over 50 \u2018X\u2019 sub-variants that haven\u2019t caused major concern so far. The main issue with XBB.1.5? Its spike proteins, which have mutated significantly.<\/p>\n \u201cIt\u2019s a mutation that researchers previously identified and predicted \u2013 one that they said if any virus got would allow it to better bind with cells. \u00a0And that is exactly what we\u2019re seeing right now,\u201d says Rossman.<\/p>\n Where exactly did this combination and mutation take place? Scientists aren\u2019t sure. \u201cA good guess might be somewhere in New York, where it really started to spread. But that is only a guess,\u201d says Rossman.<\/p>\n In short: because we\u2019ve run out of Greek letters.<\/p>\n In a bit longer: there are now so many types of Omicron (over 500 and counting<\/a>), some scientists are now naming key sub-variants after mythological creatures<\/a> to better speak about the virus\u2019s ever-growing family tree.<\/p>\n Other Omicron subvariants deemed worthy of a name include BA.2.75 (the Basilisk), XBB.1 (Hippogryph) and BF.11 (Python).\u00a0<\/strong><\/p>\n At present, there is nothing to suggest that the symptoms of infection with the new XBB.1.5 variant are different to other coronavirus strains.<\/p>\n The main symptoms of COVID-19<\/a>, according to the NHS, are:<\/p>\n Scientists aren\u2019t completely sure how much more transmissible XBB.1.5 is. But it is clear from initial data that the variant is spreading extremely quickly \u2013 the virus is growing at a rate 12 per cent faster than other types of coronavirus in the US<\/a>.<\/p>\n The picture in the UK looks very similar. Although making up only 5 per cent of all coronavirus samples sequences in the last week of 2022, the UK Health Security Agency (UKHSA) now says that XBB.1.5 could soon become the most dominant strain of coronavirus in the UK<\/a>.<\/p>\n The world, according to Rossman, could soon follow. \u201cUnless a new variant comes along that can outcompete it, which is entirely possible, I do think that this sub-variant will soon be the most dominant around the globe,\u201d he says.<\/p>\n Here is the good news. So far, there is no evidence so far that the XBB.1.5 makes people more ill than previous coronavirus variants.<\/p>\n Additionally, the World Health Organisation (WHO) has said that XBB.1.5 \u201cdoes not carry any mutation known to be associated with potential change in severity<\/a>\u201d.<\/p>\n As Rossman adds: \u201cYou\u2019re certainly more likely to catch XBB.1.5. But if you do catch it, there\u2019s no evidence you\u2019re more likely to end up in hospital or die from the virus than a few months ago.\u201d<\/p>\n Read more about COVID-19:<\/strong><\/p>\n At the moment, there is very little data to be exactly sure, but the WHO says there are signs the variant could be one of the most \u201cantibody-resistant variants to date<\/a>\u201d.<\/p>\n One preliminary study indicated that XBB.1 variants were up to 21 times more evasive against vaccine antibodies<\/a>, compared to the variant dominant in the UK since June 2022 (BA.5).<\/p>\n Another study that has not been peer-reviewed<\/a> suggests that people previously infected with the virus and<\/em> who have received three or four doses of an mRNA COVID vaccine<\/a> (such as Moderna or Pfizer) are still likely not to have the immunity needed to guard them against an XBB.1.5 infection.<\/p>\n \u201cEven for people who have had the original vaccine and boosters, the protection from getting infected and having symptoms with XBB.1.5 is very poor,\u201d says Rossman.<\/p>\n \u201cThe protection given by bivalent boosters [the second generation of vaccines, rolled out during autumn 2022 in the UK] is a little better. But it\u2019s still dramatically reduced \u2013 some estimating the efficacy is only 30 per cent or less<\/a>.\u201d<\/p>\n However, while XBB.1.5 has reduced a jab\u2019s protection from infection (and developing symptoms and long COVID), vaccines \u201cstill remain effective against severe disease<\/a>\u201d, according to the ECDC.<\/p>\n Could a new vaccine be made to combat XBB.1.5? It is possible a new generation of boosters could be produced, just like last year\u2019s bivalent boosters. However, there are no current plans for its production.<\/p>\n Like with other previous Omicron variants, our current lateral flow tests are still likely to detect the virus. However, highly-transmissible variants like XBB.1.5 may work so quickly in the body that you may take a lateral flow test after the point where the virus is detectable.<\/p>\n As Rossman explains: \u201cIt\u2019s not necessarily that the test can\u2019t pick up the virus, but that sometimes if the virus replicates really fast \u2013 like this variant might \u2013 sometimes that means the whole infection process goes so quickly in you that you only have that peak of virus that\u2019s high enough to detect for maybe six hours.\u201d<\/p>\n Unfortunately, a shorter infection time doesn\u2019t necessarily mean the time you\u2019re ill is any shorter. And while the infection time with highly transmissible variants is lower on average, this is only an average. It may take a week or longer before you exhibit symptoms and spread the virus, or it could take a day.<\/p>\n And this means, according to Rossman, lateral flow tests are still a vital tool. \u201cThey should still work and they are certainly worthwhile,\u201d he says.<\/p>\n \u201cIf you\u2019re worried, do repeat tests. And remember: if you get a negative test, it doesn\u2019t mean there\u2019s no chance you\u2019re not infected.\u201d<\/p>\n Read more about COVID-19:<\/strong><\/p>\n At the moment, scientists think that XBB.1.5 isn\u2019t more likely to cause serious disease in one individual, compared to previous variants. However, because XBB.1.5 is much more transmissible than the coronavirus variants we\u2019ve seen before, there are fears it could spread to many more people. And with more people infected, there\u2019s more chance a number of them could get seriously ill.<\/p>\n So, should we be worried about a large wave of XBB.1.5 cases? \u201cAbsolutely,\u201d says Rossman. \u201cAnything that makes the virus more transmissible can often lead to an increase in hospitalisations of vulnerable people. And even if there\u2019s no change in the severity of the virus, more people could get sick.\u201d<\/p>\n Read more about COVID-19:<\/strong><\/p>\n There\u2019s also the risk that an uptick in infections could overstretch the NHS, as Hunter explains: \u201cI don\u2019t think we\u2019re going to see anything like the number of deaths from COVID compared to January 2022. But this is happening at the same time as we\u2019ve got very high numbers of flu hospitalisations. <\/em>It is a big concern and it could be very tough.\u201d<\/p>\n For Rossman, it\u2019s not just the new variant that\u2019s a concern, but also people\u2019s attitude towards the virus. \u201cThere\u2019s been a huge sense of complacency emerging,\u201d he argues. \u201cMany people aren\u2019t wearing masks in crowded areas. The uptake of booster vaccines has been low.\u201d<\/p>\n He adds: \u201cI see people wearing surgical masks. And these do help you from spreading the virus to other people, but they don\u2019t really help protect yourself from the virus. And the more transmissible the virus gets, the less protection they offer. Instead, an FFP2 or FFP3 mask that fits well will filter out the virus, regardless of how transmissible it is.<\/p>\n \u201cWe don\u2019t need lockdowns or anything like that. But having an individual level of protection is still really important while this virus spreads.\u201d<\/p>\nWhat is the Kraken XBB.1.5 sub-variant?<\/strong><\/h2>\n
Why is the XBB.1.5 variant called the Kraken?<\/strong><\/h2>\n
What are the symptoms of <\/strong>Kraken COVID<\/strong>?<\/strong><\/h2>\n
How much more transmissible is <\/strong>XBB.1.5<\/strong>?<\/strong><\/h2>\n
Does the <\/strong>Kraken <\/strong>cause more severe disease?<\/strong><\/h2>\n
Will our current vaccines work against XBB.1.5?<\/strong><\/h2>\n
Will a lateral flow test still detect <\/strong>XBB.1.5<\/strong>? <\/strong><\/h2>\n
So how dangerous is XBB.1.5?<\/strong><\/h2>\n
About our experts<\/strong><\/h4>\n