COVID-19. A virus, an epidemic, a pandemic, the beginning of an unprecedented period characterized by uncertainty, sadness, distancing, bereavement, job loss and negative economic impact.

If you are reading this, sit down, grab a cup of coffee and buckle up because I am taking you to an eye-opening journey that will cover everything you need to know about COVID-19

Today is Saturday the 13th of June 2020. Well, random sentence that might seem unrelated to this topic. But when we talk about these kind of stuff it is important to know when these information and statistics are given to you. All the information provided in this article are valid and up-to-date at the moment of writing this article. And that’s the beauty of science, what it might be true today it might not be true tomorrow, because the more time goes by the more we learn about this virus that could either agree or disagree to what we knew yesterday.

Coronavirus is a family of respiratory viruses responsible for some conditions in humans that can space from the common cold that you and I get every year to other respiratory syndromes. It is also very common in some animal species like bats. Its name comes from the characteristic crown-like spikes that it has on its surface.

Although the name of this pandemic has changed over the course of these months, the World Health Organization (WHO) has baptized this condition with the name of COVID-19: Co (Corona), Vi (Virus), D (disease), 19 (year 2019) because in December 2019 China identified a new strain of coronavirus which was never identified before in humans, and which was causing unusual types of pneumonias. It all seemed to start in Wuhan, in the province of Hubei.

Coronavirus, COVID-19, SARS-CoV2 – which one to use?

It all sounds pretty confusing and sometimes these words are (wrongly) used interchangeably to indicate the virus or the pandemic. So let’s get familiar with the terminology here: Coronavirus refers to the family of viruses (see above); SARS-CoV2 refers to the specific strain of the virus which is causing this pandemic, it is called SARS because it is genetically linked to the strain of virus that caused SARS in 2002; COVID-19 refers to the condition caused by the virus SARS-CoV2.

Where does it come from?

Despite all the conspiracy theories out there, to date the most accredited theory is that SARS-CoV2 started with the transmission from a bat to a pangolin (see picture below) and then passed on to humans. This happened in Wuhan, and more specifically in a ‘wet market’. Very rarely the strains of coronavirus affecting animals are directly transmissible to humans. But in certain cases the virus can mutate so much so to be transmissible to humans using other animals as vectors.

It is not a laboratory invention, it is what happens when you disturb nature and offer yourself as an alternative host for the virus that lives on wildlife animals.

This is not a new thing at all. In case you didn’t know many viruses that we know today come from animals and scenarios like the one we are living today happened over and over again in the past.

HIV – 1920

HIV crossed from chimps to humans in the 1920s in what is now the Democratic Republic of Congo. This was probably as a result of chimps carrying the Simian Immunodeficiency Virus (SIV), a virus closely related to HIV, being hunted and eaten by local people. The virus was transmitted either by eating their meat, or with their blood getting into cuts and wounds on people in their course of hunting.

Ebola – 1976

Ebola virus was discovered near the Ebola River in the Democratic Republic of Congo. Similarly to HIV, the most trusted theory is that the virus was passed on from bats to non-human primates and than passed to humans via direct contacts of blood or other bodily tissues.

SARS – 2002

For example, in 2002/2003 something very similar happened when a strain of coronavirus was passed on from bats to civets (animal found in tropical Asia and Africa) and then to humans. This gave rise to an epidemic called SARS (Severe Acute Respiratory Syndrome) and it stared in China, specifically in the wet market of Foshan (southern China).

MERS – 2012

In this case a strain of coronavirus was passed on from bats to camels and than to humans. This gave rise to the Middle East Respiratory Syndrome also knows as MERS. The outbreak happened in the the Saudi Arabia peninsula.

Why China?

But why COVID-19 originated in a market? And why in China? And why SARS started in China in 2002? And how could a bat infect a civet cat in the case of the SARS? and how could a bat infect a pangolin in the case of the COVID-19? And why are there tropical animals in China?

Let’s start by clarifying what wet markets are. Wet markets are types of market where live animals are butchered and sold. These animals include chicken, bats, goats, crocodiles, civet cats, pangolins, dogs, cats, koalas, snakes and rats (just to mention a few). These markets are scattered world-wide mainly in Africa, Saudi Arabia, South-East Asia and a few areas of Latin America. But the most well-known and powerful markets are in China, like the ones where SARS and COVID-19 originated from, Foshan and Wuhan wet markets respectively. These markets are well known for the variety of wildlife that they have, animals from all over the world with each one with its own potential to carry its virus to the market.

Animals are stack in little cages one on top of the other, making it possible for cross-contamination to happen with fecal material, blood and pus to drip on other species.

This condition creates the perfect “soup” for viruses and bacteria to thrive and to be transmitted to different animals and then to humans.

Nature didn’t really predict that a bat would be over a pangolin, or over a dog, or over a camel in an environment very close to humans.

The reason why all these animals are in the same market at the same time is because of a decision made by the Chinese government a few years ago.

In 1970 China was going through a very rough period, the communist regime had the control over the food production, and it was struggling to feed its 900 million people, 36 million of which died because of very little food resources. In 1978 the Chinese regime allowed private farming and many farmers did very well with swine and poultry meat, but small farmers could not still sustain themselves, and they started to hunt and sell wild animals.

China saw a very lucrative business with the trade of wildlife, and in 1988 the government approved the “wildlife protection law”, which stated that wildlife belonged to the government and it also encouraged the domestication and breeding of wildlife. These animals were than introduced to the wet market to make profit out of them.

Parallel to this activity, an illegal commerce was also developing, with the importation of endangered species like tigers, rhinos and pangolins to China and sold in the wet markets. These animals were used not only as food, but also as aphrodisiac ingredients mainly bought by rich people.

In 2000, the markets were full of a wide variety of wildlife and this brought to the SARS outbreak in 2002, originating from Foshan. Scientists found out that the virus shared the genetic material of civet cats, and the Chinese government was forced to shut the wet market banning the breeding of wildlife.

However, a few months after, China not only reopened the wet markets, but it legalized the breeding of 54 species of wildlife, including civet cats.

We all know the very similar story that led us to this situation today.

How does the virus attack the body

The virus spreads via respiratory droplets either directly (for example a person talking/sneezing very close to us) or indirectly (for example touching contaminated surfaces).

Once the virus enters into your body from either your eyes, nose or mouth it starts by attacking your upper respiratory system from your nasal mucosa to your throat, hence the temporary loss of smell, taste, as well as flu-like symptoms. According to the CDC, symptoms might appear 5-14 days after the exposure to the virus. When the virus reaches the lungs it deposits in the air sacs called alveoli, which are extremely important structures in your lungs where oxygen can get distributed into the body via your circulatory system. The immune system tries to fight off the virus, and this generates local inflammation. Depending on the severity of the infection, fluid and pus builds up in the air sacs and this generates bronchitis and pneumonia. At this point oxygen cannot reach the blood vessels and Acute Respiratory Distress Syndrome (ARDS) might happen. It may be required to place the patient on a ventilator to help supply the oxygen.

In critical cases, the combination of lack of oxygen to the rest of the body and this persistent infection can lead to organ failure that can potentially be fatal.

The mortality rate varies depending on the age group of the affected patients as well as the presence of underlying medical conditions (i.e., hypertension, diabetes, cardiovascular conditions, chronic respiratory illnesses, cancer, immunosuppressed patients, etc).

Symptoms

COVID-19 presents with the following symptoms

• Coughing
• Throat-ache
• Fever
• Muscular and joint pain
• General feeling of being unwell
• Shortness of breath
• Congested or runny nose
• Anosmia (loss of smell sensation);
• Ageusia (loss of taste sensation);

Some people can be asymptomatic, which means that they present no symptoms at all and still be positive.

Testing

As a general rule, if you have been in contact with anyone with COVID-19 or have the symptoms discussed above, you have COVID-19 unless proved otherwise by reliable testing.

To date, two types of tests are available for COVID-19: viral tests, which tells you if you have a current infection; and antibody tests, which tells you if you have been previously exposed to the virus.

Treatment

To date, the only treatment available at the moment is supportive care (pain killers, fluids, ventilator etc…) but there is not a gold standard cure as such. However, there are several clinical trials out there that are tying to come up with a cure for it.

As of today, the FDA (Food and Drug Administration) approved the emergency use authorisation for three drugs: hydroxychloroquine and chloroquine (anti-malaria drugs), remdesivir (anti-viral medication), and a drug used to sedate people on a ventilator.

A very promising and safe treatment seems to be the hyper-immune plasma transfusion. According to preliminary studies, transfusion of plasma from people who have recovered from COVID-19 appears to be safe for severely ill patients and may speed up recovery. Again, the level of evidence for this treatment method is very premature at the moment.

Vaccine

As of today, there is no vaccine against SARS-COV2. There are about 100 active projects worldwide that are working restlessly to develop an effective and safe vaccine. Some researchers are positive to deliver the vaccines within next year.

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