According to the World Health Organisation (WHO), around 80 per cent of people contracting COVID-19, caused by the novel coronavirus, recover without requiring any specialist treatment, and suffer only mild, cold-like symptoms.
Only one in six people get seriously ill, when the disease develops further and features pneumonia.
So, how does the disease affect only a fraction of people more acutely?
According to an expert who spoke to The Guardian, there are four categories into which people getting COVID-19 can be placed:
– Those who have the virus but have no symptoms
– Those who get an infection in the upper respiratory tract, showing symptoms such as fever, cough, and headache. Such people are able to transmit the virus despite not being aware of it.
–Those showing flu-like symptoms. This is the largest group.
–Those who develop a serious illness that features pneumonia.
According to the WHO, mostly older people and those with underlying conditions such as diabetes, heart and lung issues, high blood pressure are prone to develop a serious illness.
While most people with disabilities are not inherently at higher risk for becoming infected with or having severe illness from COVID-19, some people with physical limitations or other disabilities might be at a higher risk of infection because of their underlying medical condition, as per the Centers for Disease Control (CDC).
What happens when the disease becomes more serious?
When the infection reaches the bronchial tree, or the structure which provides a passage for air to move into and out of each lung, it leads to inflammation, causing nerves to get irritated. This causes cough and fever.
If, however, the infection goes beyond the lining of the bronchial tree and to the end of air passages, where the gas exchange units are located, the situation exacerbates. Gas exchange is the process by which oxygen is delivered from the lungs to the bloodstream, and carbon dioxide is removed from the bloodstream to the lungs.
When these gas exchange units get infected, they pour out inflammatory material into air sacs at the bottom of the lungs– causing pneumonia.
When the lungs are filled with this material, they are unable to get the required amount of oxygen into the bloodstream. The body’s ability to take in oxygen and throw out carbon dioxide thus reduces. As pneumonia becomes severe, it can become life-threatening.
Is COVID-19 pneumonia especially severe?
Most types of pneumonia that are known are bacterial, and treated using antibiotics. Pneumonia caused by COVID-19 is highly severe– affecting all of the lungs instead of small parts.
Additionally, the body’s first responder mechanism– by which it tries to destroy a virus and limit its growth during an infection– gets impaired among groups of people, such as those having underlying heart and lung conditions, diabetes, and those over age 65.
What is the treatment?
Currently, apart from supportive treatment, there are no medications that can stop people from getting COVID-19 pneumonia.
Patients in intensive care are ventilated, and high oxygen levels are maintained so that the lungs are able to function in a normal way. Such patients are also treated with antiviral medication and antibiotics in order to avert the risk of contracting secondary infections.