Being Covid-resistant

This is really interesting! It appears that there exist people who naturally resist Covid! 

Understanding how they are able to avoid Covid infection, despite clearly being exposed to the virus, could lead to better vaccines, say researchers. 

A team at University College London said some people already had a degree of Covid-immunity before the pandemic started. This likely came from the body learning how to fight viruses that are related to the one which has swept the world. 

Upgrading vaccines to copy this protection, could make the jabs even more effective, the team said. 

The scientists were closely monitoring hospital staff during the first wave of the pandemic – including by taking regular blood samples. Even though they were in a high-risk environment, not everyone in the study came down with Covid. 

The results, published in the journal Nature, showed that around one-in-10 had signs of being exposed, but never had symptoms, never tested positive and never developed Covid-fighting antibodies in their blood. Part of their immune system was able to get on top of the virus before it managed to take hold – what is known as an "abortive infection". 

Blood samples showed these people already had (as in before the pandemic) protective T-cells, which recognize and kill cells infected with Covid. 

Dr. Leo Swadling, one of the researchers, said their immune systems were already "poised" to fight the new disease. These T-cells were able to spot a different part of the virus than the bit most of the current vaccines train the immune system to find. 

Vaccines are largely aimed at the spike protein, which covers the outer surface of the Covid virus. However, these rare T-cells were able to look inside the virus and find the proteins that are necessary for it to replicate. 

"The healthcare workers that were able to control the virus before it was detectable were more likely to have these T-cells that recognise the internal machinery before the start of the pandemic", Dr. Swadling added. 

These internal proteins are very similar in all related species of coronavirus, including the ones that are widespread and cause common cold symptoms. It means targeting these proteins with a vaccine could give some protection against all coronaviruses and new Covid variants. 

The team said the current vaccines were doing a good job of preventing people from becoming severely ill, but were not as good at stopping them catching Covid.