The coronavirus has found weak spots in our biology and can bypass immune defences that renders the first and last defence that can kill the host cells.

It will be surprising to know that coronaviruses are pathogens that are covered in protein and fat, but in a true sense, they are like zombies. Viruses are 'dead' but also not alive and just waiting to infect a living host. After infecting a host, it will take over the cells and multiply.

According to Dr Melanie Ott, a virologist at the Gladstone Institutes in San Francisco, the coronavirus is out there waiting for someone get it in their system, then it might be game over. Meaning when the coronavirus latches onto host cells, it will be a long or short struggle depending on the host's health and immune system.

The virion: small but terrible

Due to this highly-contagious virus, patients are walking Petri-dishes and making more viruses to infect everyone. She says that humans have become the best home for them, with some people with less severe symptoms. Asymptomatic who are not aware they're infected unknowingly transmits coronavirus to others.

She added, "It's one step ahead of us in the way that it spreads relatively undetected in some people." The coronavirus is so effective at multiplying and persisting than any virus yet known.

Also read: How Coronavirus Infection Starts in the Body, Leading to Death

One virus particle is a virion, basically unseen to the naked eye with about 1000 coronavirus that spans the width of a human hair. Now multiply that by a lot more, it will be more numerous than imaginable.

It spreads via water droplets in the air or on surfaces, and it gets into our eyes, nose, and mouth.

Once it gets into the body, the coronavirus will infect the tissues in the nose, and the healthy cells are now getting infected. This begins the attack on the host cells that can cause death.

Other viruses can be like the coronavirus, causing colds, sickening cells of the upper airways, tissues in the nose and throat are affected. Viral pneumonia can happen that infects smaller areas of a single lung.

How the virus attacks the lungs

Dr Michael Schivo, a pulmonologist at UC Davis Health, says that the coronavirus does not only sicken the cells, but also causes low oxygen.

Your lung is made up of 99% alveoli which are tiny sacs that keep the production of oxygen to the bloodstream, removing carbon dioxide during respiration.

One the virus latches and infiltrates the alveoli or air sacs, it will multiply using the host cells and damage the lungs. When the infection is in full swing, immune cells hijack and destroy healthy tissue.

Found inside the alveoli are immune cells called macrophages that protect the lungs according to Dr Michael Matthay, from the University of California, San Francisco.

Coronavirus can cause problems when the immune system is compromised and creates more neutrophils that are induced to overreact, causing a cytokine storm that destroys healthy tissue.

So with the virus already infecting more systems, your body's immune system is also getting weaker. And in some cases, alveoli will be destroyed, which means less oxygen for the body.

When this happens, fluid fills up the air sacs and breathing becomes harder, and acute respiratory distress syndrome follows that kills patients. Thus, ARDS is the real killer here and people die from COVID-19. Not only does the coronavirus infect the cells, but it also hijacks the immune system to kill the host.

Related article: Coronavirus Effects: How it Harms Human Body Organs