An estimated 10 nonillion (10 to the 31st power) individual viruses exist on our planet enough to assign one to every star in the universe a hundred million times over.

Viruses infiltrate every aspect of Avon’s natural world, seething in seawater, drifting in the atmosphere, etc. Generally considered non-living entities, this pathogen can only replicate with the help of a host, and they are capable of hijacking organisms from every branch of the tree of life from animals and plants to microorganisms including bacteria.

Viruses have been responsible for several outbreaks around the world, including the Severe Acute Respiratory Syndrom (SARS) pandemic of 2002- 2003 and the Middle East Respiratory Syndrome(MERS) outbreak in South Korea in 2015. Most recently a novel coronavirus (SARS-COV-2) also known as COVID-19 triggered an outbreak in China in December 2019 sparking international concern.

Here is a short analogy of how the pathogen-infected body.

 The virus is like a pen drive. Within itself, a pen drive contains a memory storage chip, a USB controller, some more ‘tiny nuts and bolts’ and sometimes a mini LED light. All this is encased within a metal or plastic case. It is a compact device and the only part that juts out of the case is the USB connector which can fit into the port of a desktop or laptop.

Functionally, the pen drive may contain huge data for storage, transport, copying, and visualization. But none of that can be done unless the USB connector docks onto the port of a computer. It is only then that the pen drive ‘comes to life’ and the data inside can be viewed, edited, and copied. The SARS-CoV-2 virus is very similar to the pen drive. They carry genetic material inside them (along RNA molecule) which is the blueprint for making multiple copies of themselves. However, copying this viral genome and making daughter viral particles is possible only when the spike protein (the equivalent of the USB connector) of the virus successfully binds to the ACE2 receptor protein (the equivalent of the USB port) of a host cell. Much has already been published about how the molecular interaction between the spike protein and ACE2 initiates infection of the cell and is beyond the scope of this article. Suffice to say that the docking of the spike ‘connector’ on to the ACE2 ‘port’ allows the virus to kick off a series of cellular processes that finally produce plenty of viruses.