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Dialogue: 0,0:00:00.30,0:00:05.13,Default,,0000,0000,0000,,As the pandemic continues - variants\Nhave become the latest concern
Dialogue: 0,0:00:05.13,0:00:10.32,Default,,0000,0000,0000,,with notable examples detected in South Africa,\NBrazil and the UK.
Dialogue: 0,0:00:10.32,0:00:15.74,Default,,0000,0000,0000,,But variants are complicated. Each one is\Nmade up of a collection of mutations,
Dialogue: 0,0:00:15.74,0:00:22.38,Default,,0000,0000,0000,,all of which have the potential to change the\NSARS-CoV-2 virus in unexpected ways.
Dialogue: 0,0:00:22.38,0:00:26.03,Default,,0000,0000,0000,,So what do scientists mean when they talk\Nabout variants
Dialogue: 0,0:00:26.03,0:00:29.74,Default,,0000,0000,0000,,and what might this mean for the future of the pandemic?
Dialogue: 0,0:00:30.85,0:00:34.83,Default,,0000,0000,0000,,Viruses multiply by copying their genomes\Nover and over.
Dialogue: 0,0:00:34.83,0:00:38.95,Default,,0000,0000,0000,,But like an old photocopier, these copies aren’t always perfect.
Dialogue: 0,0:00:38.95,0:00:42.100,Default,,0000,0000,0000,,Each of these imperfect copies is a variant.
Dialogue: 0,0:00:43.12,0:00:47.38,Default,,0000,0000,0000,,Normally the imperfections or mutations don’t\Nchange how the virus behaves
Dialogue: 0,0:00:47.38,0:00:51.78,Default,,0000,0000,0000,,and they can often make it less successful \Nthan the original strain.
Dialogue: 0,0:00:51.78,0:00:56.43,Default,,0000,0000,0000,,But very rarely mutations can change the virus\Nin some important ways.
Dialogue: 0,0:00:56.43,0:01:03.20,Default,,0000,0000,0000,,It could become more infectious, \Nor more able to avoid the immune system.
Dialogue: 0,0:01:03.20,0:01:06.00,Default,,0000,0000,0000,,The more a virus is allowed to replicate unchecked,
Dialogue: 0,0:01:06.00,0:01:10.68,Default,,0000,0000,0000,,the more chance it has to accumulate these rare beneficial mutations.
Dialogue: 0,0:01:10.68,0:01:15.87,Default,,0000,0000,0000,,That can occur when viruses are allowed\Nto spread quickly through a population,
Dialogue: 0,0:01:15.87,0:01:18.55,Default,,0000,0000,0000,,or if they encounter a host that’s less able to fight them,
Dialogue: 0,0:01:18.55,0:01:24.42,Default,,0000,0000,0000,,such as people with compromised immune systems\Nfrom medical treatment or those who are HIV+.
Dialogue: 0,0:01:24.42,0:01:31.18,Default,,0000,0000,0000,,If a particular set of mutations makes a variant\Nmore successful, it might become more prominent than others
Dialogue: 0,0:01:31.18,0:01:33.76,Default,,0000,0000,0000,,and that’s when it gets noticed.
Dialogue: 0,0:01:33.76,0:01:37.80,Default,,0000,0000,0000,,Epidemiologists may even decide to label it\Na ‘variant of concern’,
Dialogue: 0,0:01:37.80,0:01:42.33,Default,,0000,0000,0000,,like the examples identified in Brazil, South Africa and the UK.
Dialogue: 0,0:01:42.33,0:01:48.06,Default,,0000,0000,0000,,For months, scientists have been striving\Nto work out what’s changed in these variants,
Dialogue: 0,0:01:48.06,0:01:50.06,Default,,0000,0000,0000,,and what those changes mean.
Dialogue: 0,0:01:50.06,0:01:56.18,Default,,0000,0000,0000,,Because a variant spreading doesn’t necessarily\Nmean that it has an advantageous mutation.
Dialogue: 0,0:01:56.18,0:02:01.32,Default,,0000,0000,0000,,For example a small number of people could,\Nby chance, move a variant from one region
Dialogue: 0,0:02:01.32,0:02:06.31,Default,,0000,0000,0000,,to another, like tourists travelling back\Nfrom popular vacation spots.
Dialogue: 0,0:02:06.31,0:02:09.59,Default,,0000,0000,0000,,This could cause that variant to start \Nspreading in a new location
Dialogue: 0,0:02:09.59,0:02:13.79,Default,,0000,0000,0000,,even though there may be no significant \Nchange to the biology of the virus.
Dialogue: 0,0:02:13.79,0:02:17.20,Default,,0000,0000,0000,,This is called\Nthe Founder Effect.
Dialogue: 0,0:02:17.20,0:02:21.83,Default,,0000,0000,0000,,Understanding why a variant has emerged requires\Na combination of studies.
Dialogue: 0,0:02:21.83,0:02:28.94,Default,,0000,0000,0000,,Epidemiology can help detect and trace new variants and flag\Nnew or worrying patterns of infection.
Dialogue: 0,0:02:28.94,0:02:35.67,Default,,0000,0000,0000,,Meanwhile lab studies can start to pinpoint how the\Nmutations are changing the properties of the virus.
Dialogue: 0,0:02:35.67,0:02:42.04,Default,,0000,0000,0000,,And studies like these are starting to identify\Nmutations that have given the virus an upper hand.
Dialogue: 0,0:02:42.04,0:02:46.94,Default,,0000,0000,0000,,Some variants are faster spreading,\Nand there are hints that certain mutations
Dialogue: 0,0:02:46.94,0:02:52.51,Default,,0000,0000,0000,,could start to weaken or even evade natural\Nand vaccine derived immunity.
Dialogue: 0,0:02:52.51,0:02:58.47,Default,,0000,0000,0000,,For example, the D614G mutation, known to\Nvirologists as Doug, spread widely in the
Dialogue: 0,0:02:58.47,0:03:02.29,Default,,0000,0000,0000,,early days of the pandemic and can be seen\Nin almost all variants.
Dialogue: 0,0:03:02.29,0:03:08.44,Default,,0000,0000,0000,,It affects the spike protein that coronavirus\Nparticles use to penetrate cells. A mutation
Dialogue: 0,0:03:08.44,0:03:11.25,Default,,0000,0000,0000,,in the genome changes one amino acid for another,
Dialogue: 0,0:03:11.25,0:03:17.41,Default,,0000,0000,0000,,and makes the new variant more infectious than the original virus.
Dialogue: 0,0:03:17.41,0:03:25.66,Default,,0000,0000,0000,,N501Y also known as Nelly, is another spike protein mutation \Nwhich appears to be associated with increased transmissibility.
Dialogue: 0,0:03:25.66,0:03:34.60,Default,,0000,0000,0000,,This mutation has been detected in the B.1.1.7, \NB.1.351 and P.1 strains - all variants of concern.
Dialogue: 0,0:03:34.60,0:03:43.61,Default,,0000,0000,0000,,The worry of so-called ‘immune escape’ has also been hinted at with another spike protein mutation, E484K or Eek.
Dialogue: 0,0:03:43.61,0:03:51.27,Default,,0000,0000,0000,,Eek has been spotted in B.1.351 and P.1, the\Nvariants detected in South Africa and Brazil.
Dialogue: 0,0:03:51.27,0:03:57.96,Default,,0000,0000,0000,,Lab studies in early in 2021 showed that the\Nvariant could evade some virus-blocking antibodies,
Dialogue: 0,0:03:57.96,0:04:04.59,Default,,0000,0000,0000,,while trials in South Africa suggested that\Nthe variant reduced the efficacy of several vaccines.
Dialogue: 0,0:04:04.59,0:04:09.82,Default,,0000,0000,0000,,Despite these worries, the coronavirus is\Nactually mutating very slowly compared to
Dialogue: 0,0:04:09.82,0:04:16.70,Default,,0000,0000,0000,,something like influenza and it seems like\Nthe vaccines developed so far will remain at least partly effective.
Dialogue: 0,0:04:16.70,0:04:21.77,Default,,0000,0000,0000,,But scientists are still taking the threat\Nposed by variants seriously.
Dialogue: 0,0:04:21.77,0:04:25.64,Default,,0000,0000,0000,,And there are several things that \Ncan be done to help tackle it.
Dialogue: 0,0:04:25.64,0:04:30.00,Default,,0000,0000,0000,,Firstly, to do anything researchers need data
Dialogue: 0,0:04:30.00,0:04:37.17,Default,,0000,0000,0000,,- it’s very important to monitor and trace the emergence of \Nvariants and that isn’t always simple to do.
Dialogue: 0,0:04:37.17,0:04:41.67,Default,,0000,0000,0000,,Organisations like the COVID-19 Genomics UK\Nconsortium, or COG-UK,
Dialogue: 0,0:04:41.67,0:04:47.53,Default,,0000,0000,0000,,have stepped up their efforts to combine \Nfast sequencing with efficient data sharing.
Dialogue: 0,0:04:47.53,0:04:53.33,Default,,0000,0000,0000,,COG-UK has already sequenced over 400,000 SARS-CoV-2 genomes.
Dialogue: 0,0:04:53.33,0:04:58.91,Default,,0000,0000,0000,,Next, researchers need to look forward to\Nhow these mutated viruses could affect global
Dialogue: 0,0:04:58.91,0:05:06.62,Default,,0000,0000,0000,,vaccination efforts. Existing vaccines can be redesigned and\Ncombinations of vaccines are also being tested
Dialogue: 0,0:05:06.62,0:05:14.29,Default,,0000,0000,0000,,but it could be difficult to perform reliable \Nclinical trials amid the ongoing vaccination programmes.
Dialogue: 0,0:05:14.29,0:05:18.50,Default,,0000,0000,0000,,Right now though, work needs to continue at\Na national level.
Dialogue: 0,0:05:18.50,0:05:23.65,Default,,0000,0000,0000,,Public health policies such as track and trace, social distancing and vaccine roll-outs
Dialogue: 0,0:05:23.65,0:05:30.85,Default,,0000,0000,0000,,are powerful tools to interrupt transmission and keep tabs on new variants.
Dialogue: 0,0:05:30.85,0:05:34.44,Default,,0000,0000,0000,,After all, every time the virus is prevented\Nfrom spreading,
Dialogue: 0,0:05:34.44,0:05:36.99,Default,,0000,0000,0000,,it's also prevented from mutating,
Dialogue: 0,0:05:36.99,0:05:41.52,Default,,0000,0000,0000,,nipping new variants in the bud\Nbefore they even have a chance to develop.