Plot twist...it wasn't a man-made conspiracy from China.
COVD-19 was declared a global pandemic by the WHO on March 11, 2020. In recent weeks, the virus, SARS-CoV-2, has made its way from China, through Europe, across North America, and throughout the world. The scale of this disease and the public health measures being implemented is of a magnitude that we have never seen before. Needless to say, what once seemed like a problem within the borders of China has proven that our globalized world is more interconnected than we (ahem, and certain politicians) would like to admit. The issue is not confined within the borders of a single nation, nor will we find a solution/end to this without global cooperation.
So let's backtrack...
How did we get to a global count of nearly 140,000 confirmed cases and approximately 5000 deaths?
A number of news articles and reports point to Wuhan's Huanan Seafood Wholesale Market as the origin of the disease, though more recent research findings have raised questions about the validity of this claim. Within the past few hours, reports have emerged from China claiming that the virus actually originated from the US military. It is only right for us to be skeptical as these new "findings" emerge, especially considering political motives that may underlie these claims. In a global crisis like this, it really isn't right to prioritize pointing fingers. This is an infodemic and much as it is a pandemic and we cannot allow polarizing opinions to keep us divided in these situations of life and death.
What we know to be true is that viruses can "jump" from animal hosts to humans; a phenomenon that we have seen time and time again. The origin story of the COVID-19 zoonosis coming from the market with various different animals provides a convenient explanation for how the virus was transmitted from species to species.
Looking back on a number of coronavirus outbreaks like SARS and MERS, bats were identified as the original hosts of the virus as well. For anyone who remembers the last scene of Contagion (spoiler alert!), bats can transmit diseases to other species via saliva or feces and those other animals can, in turn, pass the disease on to humans.
The COVID-19 virus is one spiky boi with crownlike proteins on its surface for which it is named (yes, this is why the Corona beer label has a crown on it too). These proteins attach to host cell receptors and allow the virus to infect a vulnerable cell. If said viral spikes do not fit the receptors of a potential host, then the virus cannot spill over into that species. Think of it as a very devastating molecular illustration of Cinderella. In the original Brothers Grimm version of the fairytale (spoiler!), the stepsisters cut off their toes and heel to fit in the glass slipper. The coronavirus does something analogous to this in order to jump between species and if the shoe fits...then we have a pandemic on our hands.
From an evolutionary standpoint, coronaviruses want to fit the receptor and continue infecting hosts. In order to do this, they mutate and alter the structure of the viral spike proteins so that they can bind to host receptors. The genetic material of COVID-19 is RNA, a less stable nucleic acid than DNA. When the virus enters the host cell and uses the host cell machinery to read and create the genetic information needed to make more viruses, enzymes called RNA polymerases are involved. RNA polymerase has no proof-reading capacity and therefore is highly susceptible to mutations. Mutations can occur in the synthesis of viral coat proteins and the protein spikes, enabling the virus to bind to different host-receptors. If the mutation changes the spike proteins in a way that fits a host's receptor, we see the infection of various species.
As concerning as this sounds, this spike protein-receptor feature may actually be a target for future vaccines. Scientists can block the viral spikes using antibodies, which would prevent the virus from infecting host cells. You probably already know that antibiotics are ineffective on viruses (ahem, unless you are certain politicians), which is why we have to cross our fingers and hope that our immune system is capable of fighting off the virus. This typically is not a problem for the average, healthy, young person. However, for the elderly and immunocompromised who may not have a well-equipped immune system, fighting off the virus proves to be a challenge. The cool part is that after our immune system fights off the SARS-CoV-2 virus, re-infection is highly unlikely due to our immune system creating antibodies against the virus that remain in our system after the infection to keep us immune.
But...what if it mutates? Which, thanks to RNA polymerases, is very possible. The magnitude of this mutation/change on the virus and its structure will determine our level of concern.
Recent news reports have identified that a second "strain" of COVID-19 has been identified. One may be more aggressive in transmitting itself than the other, but the findings are still too premature to definitively make that claim. Some scientists are saying that the genetic differences between the two identified strains are too small to affect the production of viral proteins and therefore the infectious capacity of the virus.
So for now, please don't panic.
Apart from the molecular explanation of "How did we get here?" it is important to acknowledge that once the virus is transmitted from animals to humans, we encounter the issue of person to person transmission. This is precisely why the drastic social-distancing measures have been implemented over the past 48 hours.
The virus itself is transmitted through respiratory droplets that travel through the air when a person with the infected person coughs or sneezes. If you are in close contact (within about 6 feet) of an infected individual you are likely to have the virus land on you. Okay, so you're not standing in the middle of the street with your mouth open, BUT the virus can also be transmitted via fomites (a strange word for surfaces and objects that have been contaminated). If you touch a fomite and then inoculate yourself with the virus by touching your eyes/nose/mouth, it is more than likely that you now have COVID-19.
Now, before you start putting on a Haz-Mat suit to fetch the mail, note that viruses lose the ability to be an infectious agent on an inanimate surface over time. Also, keep in mind that a certain number of viral particles are needed to cause an infection and that fomites have not been identified as the primary route of transmission.
In times like these, we don't have a magic bullet to save the day. We are several months out from a vaccine or antivirals. Medicine cannot help up right now - not entirely. Public health measures are our greatest hope, and they require buy-in from the public. Beyond the surging numbers of cases and the plummeting stock market, the most terrifying part of this whole situation is that the resolution ultimately rests in the hands of our moral code. Will we follow guidelines to put our lives on hold for a little bit to mitigate transmission? Will we continue apocalypse shopping at Costco thus preventing others from having food and necessities? Will governments make the right calls and investments to ensure equitable access to tests? Will we account for those who are especially vulnerable with respect to paid time off and food stamps?
If you take nothing else away from this entry, please...wash your damn hands for 20 seconds with soap and water (and disinfect your phone cases too).
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