#PHE reports suggest that #SARSCoV2 carrying this variant(s) have been observed at high frequency in recent times in the South of England. At the moment there is no evidence this #variant spreads any faster or any slower. This simply hasn’t been tested yet (and of course will be)
This variant is found in an expanding outbreak but may be going up in frequency just by chance – we always have to disentangle these forces. Viruses mutate (actually #SARSCoV2 a bit slower than many viruses) and the presence of mutations in of themselves is not a cause for alarm.
N501Y was first observed back in April (#CoVGLUE) in a Brazilian isolate & in Australia over June. In recent times it’s been observed in S Africa, UK and DNK. This mutation has been shown to increase binding affinity in work from @jbloom_lab (jbloomlab.github.io/SARS-CoV-2-RBD…)...
...it is potentially adaptive in mice (tinyurl.com/y8bgnq4x). We pick up a different variant at this position as putatively adaptive in mink infections (tinyurl.com/y9mdxl2l).
N501Y has also been found in association with spike #deletions 69/70. del69/70 appears in distinct lineages (below current to 30/11/20) & can associate with binding domain #spike mutations, including N439K also suggested to play a role in antibody escape tinyurl.com/y3ayjkel.
Though deletions in this region of #spike have existed in sequenced isolates since mid March in human isolates, and predate the Danish mink outbreaks.
This preprint just out from @GuptaR_lab picks up some further candidates biorxiv.org/content/10.110… and formerly reports the recurrent emergence of the #spike double deletion.
It’s clear we need to be looking for #indels in #SARSCoV2 not just replacement events.
Given the existence of at least some of these mutations during the early 1st N hemisphere wave, it is likely all a bit more complicated than one mutation or deletion having an enormous effect on any of vaccine effectiveness, antibody recognition, disease severity or transmission.
But we should remain vigilant. We want to pick up ‘potentially’ concerning mutations early, as in this case. This is greatly aided by large genomic surveillance (@GISAID@CovidGenomicsUK@nextstrain), many data providers & the encouragement of researchers to use these resources.
At the same time there are many thousands of variants in #SARSCoV2 and the vast majority of these are expected to have no impact on #transmission (tinyurl.com/y3neo6vj). We couldn't find any in the first ~50K genomes from the #pandemic.
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SARS-CoV-2 can infect multiple mammalian carnivores and has now been detected in multiple mink farms to date 👇
Across high coverage #SARSCoV2 genomes isolated from mink @GISAID we pick up unique mutations including one in the #spike protein which has appeared at least five times in phylogenetically distant #mink lineages.
This mutation, falling within the receptor binding domain, may be a good candidate for adaptation of #SARSCoV2 to #mink hosts. While this mutation has been seen in #SARSCov2 in human circulation it is rare. Currently available mink genomes fall in the diversity of human #SARSCoV2
In our @LancetMicrobe paper we report 671 Mtb genomes 🧬from 391 patients with drug #resistant#tuberculosis in KwaZulu-Natal South Africa sampled over 6 years.
We screened for resistance to #bedaquiline, a drug now central to effective #TB treatment.
We found ~4% of patients harboured #Mtb with variants in genes known to mediate #resistance to bedaquiline/clofazimine.
Phylogenetic analyses show repeated & independent acquisitions of resistance variants, including onward transmission of resistant strains across South Africa.
Bedaquiline is a reasonably new, but now cornerstone, drug in the fight against #DRTB.
The lack of routine #bedaquiline susceptibility testing may allow these #resistant strains to continue to spread, unwatched, posing further significant challenges to #TB treatment & control.
Our paper on the emergence of genomic diversity and recurrent mutations in #SARSCoV2 is now out in #IGEtinyurl.com/yb4mxhes As with many others, we’ve been working hard tracing the evolution of #SARSCoV2 using thousands of genomes 🧬shared on @GISAID. Here's what we found👇/1
Here we analyse >7500 viral genomes from all around the 🗺️ We show that the time of the host-jump of #SARSCoV2 into humans dates to late last year, consistent with estimates by several others
Genetic data shows #SARSCoV2 only recently started infecting us & was detected fast. /2
Around the world we see large amounts of regional genetic diversity with marked & repeated intros to many countries
Eg. we place genomes sampled from UK patients throughout the global tree. There is no such concept as a patient zero (see @nextstrain also for visualisations) /3
On our hunt for past malaria we were fortunate to obtain a collection of blood-stained medical #microscope#slides prepared for diagnostics purposes in 1944 in Spain, one of the last footholds of #malaria in Europe. (2/7)