The word of 2020 will undoubtedly be Corona. You have to be living under a rock to have not heard of Covid-19. While some people have been quick to say that this is Nature’s way of retaliating against human excess, it is not really about retaliation. Retaliation means there is an us vs them, humans vs Nature, as if we are pitted against each other in a war. 

No, Covid-19 is simply the logical progression of what happens as one species (humans) destroys the world. Let’s take a step back and look at where and how Covid-19 became such a global disaster.

Covid or Corona?
Covid-19 (coronavirus disease 2019) is the disease caused by a coronavirus named SARS-CoV2. Coronaviruses are part of a large family of viruses that cause respiratory illnesses including severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). All of these are zoonotic diseases (or zoonoses) which means they came from an animal and jumped species to humans. This is nothing new. HIV, Zika, Ebola, and Nipah are also zoonoses.
 
How do these jump from animals to humans?
Any infection can be picked by one or more different methods - by direct contact (saliva, faeces, blood, other body fluids, bites, scratches) or indirect contact (by coming into contact with places where the animal lives/uses, or objects/surfaces contaminated with germs). Germs can also be passed on through contaminated food (when not properly cooked) or water and through vectors such as ticks or mosquitoes (malaria, for eg.). 
 
So an infection can come from another person through these means but also from animals. You may wonder then how people with pets don’t fall ill often. Well, first, we tend to take good care of our pets so they are healthy, secondly we do develop immunity from exposure to low levels of germs. In fact studies have shown children who spend time with dogs and cats and other pets tend to have a stronger immune system. 
 
When germs that infect a species jump to another species (by one of the above methods), very rarely do they cause an infection. They usually just die out because they are not adapted to this new host species (new for the germ). Once in a while, the germ mutates in just the right way to cause an infection in the new host (human or otherwise). Several things have to come together for the disease to become a huge problem for the new host species - first, contact between germ and the animal; second, germ has to mutate in a way that causes an infection in the animal; third, the germ should have a high level of virulence (measure of severity of disease); and finally the animal should then pass the infection on to others of its kind. 
 
Humans have caused this pandemic
Zoonoses from domesticated species is not usually an issue but when we encounter wild animals then it can be an issue. How do we encounter wild animals? Well as a society we have been destroying wild habitats with settlements, industries, and tourism and so on. As we do this, the chances of humans and animals coming into close contact increase. In addition, these animals don’t have any place to go (because we have destroyed their home) and so start coming into what we think of as our space - the housing areas of industries, the villages, etc. Now the chance to interact (through the ways listed earlier) with these animals and germs they carry has increased by a huge number. These animals are also stressed with loss of food and home and bumping into us. Stress is known to increase levels of virus load.
 
We’ve now happily created a situation ideal for a germ to jump ship and infect us. This is how something like SARS-CoV2 infected someone in China. (Yes, eating/handling wild meat can be a means of transmission as well if hygiene is poor or the meat is not properly cooked). Since we haven’t encountered it till now, we don’t have any immunity against it. Covid--19 is spread through the air when an infected person sneezes or contaminates a surface with their saliva or nasal fluids. So a combination of luck, high virulence of the virus, easy mechanism of spreading, and of course most importantly the high densities in which people live, high levels of human movement (travel), made it easy for the virus to spread like wildfire across the globe. 
 
So is Covid-19 an anomaly?
Well, scientists are warning us to expect more such situations in the future. We have already seen outbreaks in the past. Take a peek at the website of the Centre for Disease Control (CDC) and it has a page on pandemics in the past. In the 20th century alone we have had the Spanish Influenza (1918), H1N1 (1957-58), H3N2 (1963), and H1N1 (2009). We’ve also had SARS (2002-03) and MERS (2012-13) which didn’t spread as wide but still affected several countries with cases still reported here and there. Now with the rapid destruction of natural habitats, we are hugely increasing the likelihood of pandemics/epidemics of zoonotic diseases. In today’s interconnected world, as Covid-19 has shown us, it takes very little time for a disease to spread. 
 
The Future
Once this crisis is past, we have two choices - either go back to business as usual, with industries humming away, forests and water bodies being destroyed, species annihilated because we want the latest gadgets, continue with our fads, OR we could take a hard look at ourselves, our lifestyles and reduce our consumption. This would include the kinds of food we eat, the things we buy, the travel options we make (daily and otherwise), the way we dispose of our waste, and what we demand of our governments. 

Change though has to start with us. Can we not consciously work to reduce the amount of packaged items we buy - food and other things? Buying food without throwaway packaging will support small businesses and local producers, reduce garbage generated, and make us eat fresh food which is healthier. Can we not use the same phone/computer/or any gadget till it completely dies? (Electronic waste takes a lot of rare resources, destroying the Earth, and is very hard to dispose of safely). Can we not segregate and compost our waste, recycle what can be recycled, and reuse as much as possible? 

So, no Covid-19 is not Nature’s declaration of war on humanity. It is a sign of what happens when we disrupt the natural order, when we forget that we too are a part of Nature. We too are a species, a part of the animal kingdom. The natural world is complex and interlinked; destroying natural resources has a huge ripple effect that can be very hard to counter. We’ve seen this with Covid-19; one person somewhere got infected (it doesn’t matter where), and the entire world has come to a standstill. The impact on livelihoods, on food production, on travel, on economies, on survival of people, is going to echo for months, maybe years.