Contributed by – Healthians team
While the novel Coronavirus is wreaking havoc across the world, most of us are grappling with questions about it. Why exactly are people dying of this disease? What is causing these deaths? How is it that the disease is turning from cough and fever to death in a matter of weeks? Why is it that some people are experiencing mild symptoms and some are dying from the infection?
Scientists and experts across the world are still trying to figure out the novel coronavirus. However, it has become increasingly clear that the immune system has a very important role to play in whether someone recovers or succumbs to the infection. In fact, a majority of coronavirus related deaths can be attributed to a person’s immune system going haywire rather than the damage caused by the virus itself. So what exactly is happening in your body when you get infected and who is at risk of getting a severe form of the infection.
When your body gets infected by the virus, your innate immune system kicks in and starts responding. The immune systems releases proteins called interferons that interfere with the virus’s ability to multiply in the body. Interferons engage other immune cells to stop the virus from spreading. This innate immune response manifests itself in the first symptoms of being sick. These symptoms both alert the body to the attack -like in the case of fever, as well as try to expel the particles – through cough or diarrhoea.
The kind of symptoms a person suffers from depends on where the virus establishes itself. The coronavirus enters the body through droplets and latches on to specific proteins that are most abundantly found in the lungs and the intestines, which is why Covid-19 is primarily a respiratory illness, but, can cause diarrhoea if it enters the intestines too.
The innate immune system tries to contain the virus and stop it from spreading too widely, to allow the second wave of immune system – the adaptive immune system to kick in with a virus-specific response. This adaptive immune system also creates the immunity necessary for a person to fight reinfection.
While this is ideally how the immune system works, in some people, however, the virus will replicate and spread too rapidly for the immune system to control it. This happens mostly in two cases, one is when a person is exposed to large amounts of the virus for a long time – for. e.g. doctors and other healthcare workers. The other case is when the immune system of the person is compromised as in the case of elderly people or those suffering from other illnesses.
If the virus establishes itself in the lungs it can cause pneumonia as more and more cells become infected. Here, some of the damage is caused by the virus, but, some also by the immune system which keeps on trying to destroy the virus and get rid of the infected cells.
From this position, the disease can still go in two different directions. Either the immune system can remain stable and mount the response necessary to combat the infection, or it can go into a total spiral and start to overreact, generating more and more inflammatory proteins, called cytokines, in a desperate attempt to eliminate the virus. It is this second response which causes severe infections, acute respiratory disease and, even death.
The elderly and those whose immunity is compromised are predominantly at risk for this kind of response as their under active immune system suddenly goes in to hyperactivity. This particular phenomenon is also something seen in other corona viruses as well, like SARS and MERS.
While scientists across the globe are trying to come up with antiviral medications to combat the illness, for most of us right now, the best defense would be to stay at home, get full body checkup and check our immunity, making sure we do not suffer from any deficiencies and do everything to strengthen ourselves, because after the lock down opens up and all of us would step out to resume our work, we’ll be exposed to external factors which would put us at risk. Therefore it’s very important to make sure we check our immunity levels and take necessary steps to strengthen it to stay protected from any illnesses.