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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: 0,0:00:05.13,0:00:07.82,Default,,0000,0000,0000,,with notable examples detected \Nin South Africa,
Dialogue: 0,0:00:07.82,0:00:10.32,Default,,0000,0000,0000,,Brazil and the UK.
Dialogue: 0,0:00:10.32,0:00:12.94,Default,,0000,0000,0000,,But variants are complicated.
Dialogue: 0,0:00:12.94,0:00:15.74,Default,,0000,0000,0000,,Each one is made up \Nof 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 \Nthe SARS-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 \Nfor the future of the pandemic?
Dialogue: 0,0:00:30.85,0:00:34.83,Default,,0000,0000,0000,,Viruses multiply by copying \Ntheir genomes over and over.
Dialogue: 0,0:00:34.83,0:00:38.95,Default,,0000,0000,0000,,But like an old photocopier, \Nthese copies aren’t always perfect.
Dialogue: 0,0:00:38.95,0:00:42.29,Default,,0000,0000,0000,,Each of these imperfect copies \Nis a variant.
Dialogue: 0,0:00:43.12,0:00:47.38,Default,,0000,0000,0000,,Normally the imperfections or mutations \Ndon’t change 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 \Nchange the virus in 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 \Nto replicate unchecked,
Dialogue: 0,0:01:06.00,0:01:10.68,Default,,0000,0000,0000,,the more chance it has to accumulate \Nthese rare beneficial mutations.
Dialogue: 0,0:01:10.68,0:01:15.73,Default,,0000,0000,0000,,That can occur when viruses are allowed\Nto spread quickly through a population,
Dialogue: 0,0:01:15.73,0:01:18.55,Default,,0000,0000,0000,,or if they encounter a host \Nthat’s less able to fight them,
Dialogue: 0,0:01:18.55,0:01:22.29,Default,,0000,0000,0000,,such as people with compromised\Nimmune systems from medical treatment
Dialogue: 0,0:01:22.29,0:01:24.42,Default,,0000,0000,0000,,or those who are HIV+.
Dialogue: 0,0:01:24.42,0:01:28.66,Default,,0000,0000,0000,,If a particular set of mutations makes \Na variant more successful,
Dialogue: 0,0:01:28.66,0:01:31.10,Default,,0000,0000,0000,,it might become more prominent than others
Dialogue: 0,0:01:31.10,0:01:33.76,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\Nto label it a ‘variant of concern’,
Dialogue: 0,0:01:37.80,0:01:42.33,Default,,0000,0000,0000,,like the examples identified in Brazil, \NSouth Africa and the UK.
Dialogue: 0,0:01:42.33,0:01:45.73,Default,,0000,0000,0000,,For months, scientists \Nhave been striving to work out
Dialogue: 0,0:01:45.73,0:01:49.96,Default,,0000,0000,0000,,what’s changed in these variants,\Nand what those changes mean.
Dialogue: 0,0:01:49.96,0:01:52.98,Default,,0000,0000,0000,,Because a variant spreading \Ndoesn’t necessarily mean
Dialogue: 0,0:01:52.98,0:01:56.18,Default,,0000,0000,0000,,that it has an advantageous mutation.
Dialogue: 0,0:01:56.18,0:01:59.71,Default,,0000,0000,0000,,For example a small number of people \Ncould, by chance,
Dialogue: 0,0:01:59.71,0:02:01.87,Default,,0000,0000,0000,,move a variant \Nfrom one region to another,
Dialogue: 0,0:02:01.87,0:02:05.59,Default,,0000,0000,0000,,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: 0,0:02:17.20,0:02:19.50,Default,,0000,0000,0000,,Understanding why a variant has emerged
Dialogue: 0,0:02:19.50,0:02:21.83,Default,,0000,0000,0000,,requires a combination of studies.
Dialogue: 0,0:02:21.83,0:02:25.26,Default,,0000,0000,0000,,Epidemiology can help detect \Nand trace new variants
Dialogue: 0,0:02:25.26,0:02:28.44,Default,,0000,0000,0000,,and flag new or worrying \Npatterns of infection.
Dialogue: 0,0:02:28.44,0:02:31.61,Default,,0000,0000,0000,,Meanwhile lab studies \Ncan start to pinpoint
Dialogue: 0,0:02:31.61,0:02:35.51,Default,,0000,0000,0000,,how the mutations are changing \Nthe properties of the virus.
Dialogue: 0,0:02:35.51,0:02:39.06,Default,,0000,0000,0000,,And studies like these \Nare starting to identify mutations
Dialogue: 0,0:02:39.06,0:02:42.04,Default,,0000,0000,0000,,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: 0,0:02:46.94,0:02:51.62,Default,,0000,0000,0000,,could start to weaken or even evade \Nnatural and vaccine derived immunity.
Dialogue: 0,0:02:52.51,0:02:58.22,Default,,0000,0000,0000,,For example, the D614G mutation, known to\Nvirologists as Doug, spread widely
Dialogue: 0,0:02:58.22,0:03:02.29,Default,,0000,0000,0000,,in the early days of the pandemic \Nand can be seen in almost all variants.
Dialogue: 0,0:03:02.29,0:03:04.66,Default,,0000,0000,0000,,It affects the spike protein
Dialogue: 0,0:03:04.66,0:03:07.82,Default,,0000,0000,0000,,that coronavirus particles \Nuse to penetrate cells.
Dialogue: 0,0:03:07.82,0:03:11.25,Default,,0000,0000,0000,,A mutation in the genome changes \None amino acid for another,
Dialogue: 0,0:03:11.25,0:03:15.53,Default,,0000,0000,0000,,and makes the new variant \Nmore infectious than the original virus.
Dialogue: 0,0:03:17.41,0:03:22.37,Default,,0000,0000,0000,,N501Y also known as Nelly, \Nis another spike protein mutation
Dialogue: 0,0:03:22.37,0:03:25.66,Default,,0000,0000,0000,,which appears to be associated \Nwith increased transmissibility.
Dialogue: 0,0:03:25.66,0:03:30.51,Default,,0000,0000,0000,,This mutation has been detected\Nin the B.1.1.7, B.1.351
Dialogue: 0,0:03:30.51,0:03:34.78,Default,,0000,0000,0000,,and P.1 strains – \Nall variants of concern.
Dialogue: 0,0:03:34.78,0:03:38.37,Default,,0000,0000,0000,,The worry of so-called ‘immune escape’ \Nhas also been hinted at
Dialogue: 0,0:03:38.37,0:03:43.61,Default,,0000,0000,0000,,with another spike protein mutation, \NE484K or Eek.
Dialogue: 0,0:03:43.61,0:03:47.24,Default,,0000,0000,0000,,Eek has been spotted in B.1.351 and P.1,
Dialogue: 0,0:03:47.24,0:03:50.02,Default,,0000,0000,0000,,the variants detected \Nin South Africa and Brazil.
Dialogue: 0,0:03:51.27,0:03:55.24,Default,,0000,0000,0000,,Lab studies in early in 2021 \Nshowed that the variant could evade
Dialogue: 0,0:03:55.24,0:03:57.96,Default,,0000,0000,0000,,some virus-blocking antibodies,
Dialogue: 0,0:03:57.96,0:04:00.09,Default,,0000,0000,0000,,while trials in South Africa suggested
Dialogue: 0,0:04:00.09,0:04:03.61,Default,,0000,0000,0000,,that the variant reduced \Nthe efficacy of several vaccines.
Dialogue: 0,0:04:04.59,0:04:08.82,Default,,0000,0000,0000,,Despite these worries, the coronavirus \Nis actually mutating very slowly
Dialogue: 0,0:04:08.82,0:04:11.51,Default,,0000,0000,0000,,compared to something like influenza
Dialogue: 0,0:04:11.51,0:04:14.08,Default,,0000,0000,0000,,and it seems like the vaccines \Ndeveloped so far
Dialogue: 0,0:04:14.08,0:04:16.70,Default,,0000,0000,0000,,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 \Nresearchers need data.
Dialogue: 0,0:04:30.00,0:04:33.86,Default,,0000,0000,0000,,It’s very important to monitor and trace \Nthe emergence of variants
Dialogue: 0,0:04:33.86,0:04:35.86,Default,,0000,0000,0000,,and that isn’t always simple to do.
Dialogue: 0,0:04:36.83,0:04:41.94,Default,,0000,0000,0000,,Organisations like the COVID-19 \NGenomics UK consortium, or COG-UK,
Dialogue: 0,0:04:41.94,0:04:45.12,Default,,0000,0000,0000,,have stepped up their efforts \Nto combine fast sequencing
Dialogue: 0,0:04:45.12,0:04:47.53,Default,,0000,0000,0000,,with efficient data sharing.
Dialogue: 0,0:04:47.53,0:04:52.41,Default,,0000,0000,0000,,COG-UK has already sequenced \Nover 400,000 SARS-CoV-2 genomes.
Dialogue: 0,0:04:53.33,0:04:57.91,Default,,0000,0000,0000,,Next, researchers need to look forward \Nto how these mutated viruses
Dialogue: 0,0:04:57.91,0:05:00.78,Default,,0000,0000,0000,,could affect global vaccination efforts.
Dialogue: 0,0:05:00.78,0:05:03.42,Default,,0000,0000,0000,,Existing vaccines can be redesigned
Dialogue: 0,0:05:03.42,0:05:06.62,Default,,0000,0000,0000,,and combinations of vaccines \Nare also being tested
Dialogue: 0,0:05:06.62,0:05:10.49,Default,,0000,0000,0000,,but it could be difficult to perform \Nreliable clinical trials
Dialogue: 0,0:05:10.49,0:05:13.34,Default,,0000,0000,0000,,amid the ongoing vaccination programmes.
Dialogue: 0,0:05:14.29,0:05:18.50,Default,,0000,0000,0000,,Right now though, work needs \Nto continue at a national level.
Dialogue: 0,0:05:18.50,0:05:21.05,Default,,0000,0000,0000,,Public health policies \Nsuch as track and trace,
Dialogue: 0,0:05:21.05,0:05:23.65,Default,,0000,0000,0000,,social distancing and vaccine roll-outs
Dialogue: 0,0:05:23.65,0:05:26.62,Default,,0000,0000,0000,,are powerful tools \Nto interrupt transmission
Dialogue: 0,0:05:26.62,0:05:29.44,Default,,0000,0000,0000,,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 \Nis prevented from 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.