Scientists have made a breakthrough in understanding why some people are able to avoid getting infected with Covid. A recent study involved giving a small dose of the virus to healthy adults to see how their immune systems responded. The results revealed that there are differences in the immune response that could explain why some individuals are able to fight off the virus before it fully takes hold.
Dr. Marko Nikolić, the senior author of the study at University College London, stated that the findings provide new insights into the early stages of infection and how the immune system can either clear the virus quickly or allow it to cause symptoms. This discovery could be instrumental in developing treatments and vaccines that mimic the body’s natural defense mechanisms.
The study, conducted as part of the UK Covid-19 Human Challenge study, involved 36 healthy adult volunteers who were given a small dose of the virus through the nose. The participants were closely monitored to track the activity of immune cells in their blood and nasal lining before, during, and after infection. The results showed that there were three distinct groups among the volunteers: those who developed a sustained infection and became ill, those who tested positive briefly without developing a full infection, and those who experienced an “abortive infection” without ever testing positive.
One interesting finding was that individuals in the abortive and transient infection groups had high levels of activity in a gene called HLA-DQA2 even before being exposed to the virus. This gene is responsible for alerting the immune system to the presence of foreign invaders, such as viruses. This heightened immune response seemed to prevent the virus from establishing a full infection in these individuals.
However, it’s important to note that even those with a strong immune response were not completely immune to the virus. Some participants who initially showed a robust immune response still ended up contracting Covid in the community later on. The study also found that individuals who developed a full infection had a slower immune response in their nasal cells, allowing the virus more time to take hold.
Overall, these findings pave the way for developing more effective treatments and vaccines that can mimic the body’s natural protective responses. By understanding how the immune system responds to Covid at the earliest stages of infection, researchers can work towards developing strategies to help prevent the virus from causing severe illness. This research is a crucial step forward in the fight against Covid and could potentially lead to improved outcomes for those who are infected with the virus.
