Thread by @Bhekisisa_MG

There will be a scientific panel discussion on the latest developments with the new #COVID19SA variant #501yv2 currently dominating in the country. Follow along as we live-tweet the briefing starting shortly. bit.ly/38SXhTG

It's been a month since we first described the new variant and we've learnt a lot since then. So this is an update on that from the scientists that have been working on this issue. - @ProfAbdoolKarim #Covid19InSA #501yv2 bit.ly/38SXhTG

Scientists from @krisp_news led a consortium of researchers around the country that sequenced various samples of the virus and identified the new variant with over 20 mutations - @ProfAbdoolKarim #501YV2 #COVID19SA bit.ly/38SXhTG

This was part of routine sequencing done from the team since April 2020. They were commonly seeing only 1 to 2 mutations per month, this new variant was unusual because it has 23 mutations - @ProfAbdoolKarim #501YV2 #COVID19SA bit.ly/38SXhTG

In the 1st wave, we reached a peak in July. We then saw the new variant emerging in the latter part of October as we went into the 2nd wave. This wave has reached new heights, seeing more cases and deaths than we ever saw before. - @ProfAbdoolKarim bit.ly/38SXhTG

Two mutations in the virus — called N501Y and K417N — cause key changes to the part of the virus that allows it to bind more strongly to human cells and transmit better - @ProfAbdoolKarim #501YV2 #COVID19SA bit.ly/38SXhTG

The virus being able to attach itself to our cells better is reflected in the high number of #COVID19SA cases and the increase in the proportion of positive tests we have seen in South Africa. - @ProfAbdoolKarim #501YV2 bit.ly/38SXhTG

We have been seeing a drastic difference in the first wave when compared to the second wave and we can see it in the impact it's having in the provinces. - @ProfAbdoolKarim #Covid19InSA #501YV2 bit.ly/38SXhTG

We have seen that the new variant has spread much faster, it is left to be seen if it will end much faster. Mathematical modelling estimates that the virus is 50% more transmissible than previous variants. - @ProfAbdoolKarim #501YV2 #COVID19SA bit.ly/38SXhTG

How does the #501YV2 compare to the B.1.1.7 variant identified in the UK? The #B117 is 56% more transmissible than pre-existing variants. No evidence that it is causing more severe disease. - @ProfAbdoolKarim bit.ly/38SXhTG

Data from the Western Cape department of health shows that there is no notable difference in those admitted during the second wave when compared to the first. - @ProfAbdoolKarim #COVID19SA bit.ly/38SXhTG

This analysis also found that the risk of dying from #COVID19 was no different among age groups when compared across both waves. - @ProfAbdoolKarim #Covid19InSA bit.ly/38SXhTG

Current data shows that the new variant is not causing more severe disease but is putting more pressure on hospitals which may lead to an increase in the number of @COVID19SA deaths - @ProfAbdoolKarim bit.ly/38SXhTG

As we go into our second wave, we see the number of recorded deaths once again exceeding those predicted for that time period - @ProfAbdoolKarim #COVID19SA

Will #COVID19 vaccines work against the new variants? We don't yet have an answer. We're expecting an answer very soon. But it's too early to speculate until we know more. - @ProfAbdoolKarim #501YV2 bit.ly/38SXhTG

The spike protein, which sits on the surface of the coronavirus, is the point at which the virus attacks itself to human cells. This part of the virus is shaped almost like a torso. - @ProfAbdoolKarim bit.ly/38SXhTG

One of the key changes occurred at the 'left shoulder' and 'neck' sections of the protein. These mutations allow the virus have a higher binding affinity, ie to better stick to human cells. - @ProfAbdoolKarim #501YV2 bit.ly/38SXhTG

One of these mutations — E484 — allows the variant to escape antibodies generated by the original version of the virus circulating in communities. But this does not yet factor in T cell immunity - @ProfAbdoolKarim bit.ly/38SXhTG

48% of South Africans infected in the 1st wave has complete immune escape to the #501YV2 variant and 90% showed reduced immunity, new research shows. - @ProfAbdoolKarim bit.ly/38SXhTG

Vaccines like Pfizer and Moderna with 95% efficacy are among the most effective vaccines we have for any disease. These help achieve a critical of reducing illness and hospitalisation. - @ProfAbdoolKarim #COVID19SA bit.ly/38SXhTG

At this stage, South Africa should not change its #VaccineRolloutStrategySA. But this is a mammoth task and needs all hands on deck. New evidence on the variant doesn't change that. - @ProfAbdoolKarim #501YV2 bit.ly/38SXhTG

What do we know:
- The virus spreads around 50% faster
- Current data suggests the variant is not more severe
- Published studies suggest that natural antibodies are less effective
- But it's too early to know what this means for vaccine antibodies
bit.ly/38SXhTG

When we talk about mutations, we're talking about changes to the genetic structure of the virus. As the virus spreads, you get errors in this code. This error is called a mutation and are mostly insignificant. - @rjlessells @krisp_news #501YV2 bit.ly/38SXhTG

The high number of mutations and their location at a key part of the virus where it latches onto human cells, which was out of keeping with what was seen in other viruses, is what flagged the #501YV2 variant. - @rjlessells bit.ly/38SXhTG

These changes made us concerned and made us want to do all this extra work over the holidays and beyond to really understand the significance of these mutations seen - @rjlessells #501YV2 bit.ly/38SXhTG

There are two parts of the virus which serve as flags to the immune system - the receptor-binding domain and the N terminal. Mutations in these regions signal that the new forms of the virus may be able to evade antibodies - Prof Penny Moore bit.ly/38SXhTG

There are limitations to what can be seen in labs so we need to wait for data from clinical trials and epidemiological evidence to understand the seriousness of immune evasion of the new variants and what this means for #COVID19Vaccines - Prof Penny Moore bit.ly/38SXhTG

Vaccines are very complex and can create different kinds of immunity. So the evidence we have so far doesn't mean that vaccines won't work against the new variants. But the world has underestimated this virus, it can adapt. - Prof Sigal bit.ly/38SXhTG

This virus is adapting to us. We have reasons to be concerned because the virus is able to escape from previous antibodies. Answers with live virus are a bit worse. - Prof Sigal's team will be releasing new research on this soon bit.ly/38SXhTG

The question we are left with: if the virus is escaping from previous immune responses then what is happening with re-infection? Re-infection is when someone gets infected for a second time after recovering from #COVID19. - bit.ly/38SXhTG

Re-infection can happen for two potential reasons:
1. There is a short-lived or inadequate immune response to the virus
2. The body has not been stimulated to create an immune response against the new variant
More research needed to find the answer. bit.ly/38SXhTG

We don't yet know what drives re-infection and we have not yet seen that risk of re-infection is increasing because of the new variant so its an area we need to monitor closely. - Prof Mlisana #COVID19SA bit.ly/38SXhTG

We've found no real difference in people admitted to hospitals in the Western Cape between the first and second wave. We've seen more deaths but that is because of the higher number of cases overall - Prof Mary-Ann Davies #COVID19SA #501YV2

When you look at the proportion of #COVID19SA deaths it is still largely the same, which indicates the new #501YV2 variant is not more severe - Prof Davies bit.ly/38SXhTG

Looking at 3 districts: Nelson Mandela Bay in EC, City of Cape Town in WC, eThekwini in KZN to assess severity of disease during second wave when large number of cases in these areas. - Dr Waasila Jassat bit.ly/38SXhTG

Higher mortality rates likely reflect increasing pressure on the healthcare system. Even though there are more deaths in the second wave, there was no difference in mortality rates between the two waves. - Dr Jassat bit.ly/38SXhTG

It also doesn't appear that more young people are being admitted to hospitals or dying as a result of disease due to the new variant - Dr Jassat #COVID19SA bit.ly/38SXhTG

There could be other factors contributing to what we're seeing and the second wave is still ongoing. There is still more research needed to fully assess how the new variant contributed to what we're seeing - Dr Jassat bit.ly/38SXhTG

You need to know your enemy so you can fight that well. It's very important to know, even if our enemy is a more transmissible virus. - Prof Tulio de Oliveira #501YV2 bit.ly/38SXhTG

This team of clinicians and scientists helps us to work quickly and is what allows us to get results within weeks of first identifying the new variant #501YV2 - @Tuliodna @krisp_news bit.ly/38SXhTG

Our detailed genomic surveillance allowed us to identify this variant as early as we did. We cannot relax safety measures. If we get complacent, we could see more waves with this more transmissible variant - @Tuliodna #501YV2 bit.ly/38SXhTG

We want to fight misinformation and the falsehoods that are being spread. In sharing the truth, we all are beneficiaries. Thank you to all for joining us. - @ProfAbdoolKarim

Did you miss today's update on the #501YV2 #COVID19SA variant? Get the slides from @ProfAbdoolKarim here: bhekisisa.org/wp-content/upl…