Scientists have a hypothesis, why COVID-19 affects older people more

Both old and young people can get COVID-19. However, healthy young people usually get better without any treatment at all, while older patients can experience some life-threatening complications. Why older people are at higher risk of more difficult COVID-19 cases? Scientists from ETH Zurich have a good hypothesis.

COVID-19 affects older people more and scientists are not entirely sure why. Image credit: governortomwolf via Wikimedia (CC BY 2.0)

As you get older, your immune system becomes weaker. In other words, you become more susceptible to all kinds of infections, not just COVID-19. Older people are infected with flu more and experience complications much more frequently. But scientists believe that there may be other explanations about why COVID-19 is killing more older people.

Aging is a terrible thing. Our entire bodies deteriorate with time and lung tissue is no exception. Scientists note that mechanical properties of our cells change. And SARS-CoV-2 virus, which causes COVID-19 disease, might be taking advantage of those changing characteristics of our cells. In this case specifically, lung tissue becomes stiffer as we age, which may be creating a perfect domain for the viruses to spread.

SARS-CoV-2 gets into our bodies through mucosal cells of the respiratory tract. It basically hijacks our cells and uses them to produce more viruses. These new viruses spread to other cells and the process continues, causing a major infection and a strong immune response.

SARS-CoV-2 has no problem invading cells in younger or older people – everyone can get infected. However, children experience very mild symptoms, while older people get really sick and sometimes even die. This could be because cells in the respiratory system become stiffer due to more protein fibres forming in the tissue with age. Scientists believe that this interferes with the function of the cells slightly, helping viruses to hijack these cells and use them to proliferate in the organism.

Scientists are going to confirm this hypothesis with in-vitro models. The ultimate goal is to understand how SARS-CoV-2 spreads inside of the body and how can we close those doors for it. Caroline Uhler and G. V. Shivashankar, authors of the paper, said: “he quest for drugs should also include inhibitors that intersect with coronavirus replication and the mechanical properties of cells”.

If the relation between mechanical properties of cells and infections is confirmed, it would help treating COVID-19 and other infections that attack older people more. COVID-19 is not as scary for younger people, which is why they do not follow all the guidelines when it comes to social distancing and other preventive measures. However, if you are young you should think about those people who may get affected by the virus that you are spreading. You should not contact other people not just to protect yourself, but to protect others as well.

 

Source: ETH Zurich