While we don’t know much about the new virus “COVID-19”, there has been a longstanding coronavirus history.
The first coronavirus was isolated in chicken embryos in 1937 by Beaudette and Hudson.
The first report of a human coronavirus was in 1965. Tyrrell and Bynoe were the first to isolate a virus taken from the nasal washings, a procedure, of a male child. The symptoms were similar to a common cold and the washing itself was able to induce cold symptoms to others.
Since its discovery, Tyrrell led a group of virologists in the 1960s to learn more about human strains and animal viruses. The viruses studied were bronchitis virus, mouse hepatitis virus, and transmissible gastroenteritis virus of swine. All of these items were later grouped and classified as coronavirus (CoV), a new class of viruses.
The word corona is of Latin origin, with the meaning being ‘crown’. When one observes this new virus under electron micrographs, multiple crown-like surface projections covering the virus can be seen. Coronaviruses are a medium-sized enveloped positive-stranded RNA viruses.
The coronavirus is also a type of virus that falls under zoonotic diseases. This allows the virus to jump from animals to humans and depending on the virus. Depending on the virus, there is a definite set of host range they can infect.
In short, viruses are species-specific.
There are currently four main subgroups within coronaviruses: alpha, beta, gamma, and delta.
Continue reading to learn more about coronavirus history across animals and humans.
Different species have separate versions of the coronavirus. Since the start of coronavirus history in the 1930s, coronavirus has been identified in multiple animal species. The symptoms and outcomes for each species are also different, due to the variations in the virus. There is no crossover protection between any vaccine of two different coronaviruses of different species.
Animal coronavirus diseases affect chickens, turkeys, bats, cows, horses, dogs, cats and so on.
In humans, coronaviruses mainly cause respiratory tract infections, whereas in animals, they cause varying illnesses of different degrees. It can cause respiratory, enteric, hepatic and neurological diseases. Most veterinarians treat coronaviruses in puppies and calves. Animal coronaviruses’ symptoms are very different from human coronaviruses and they are not life-threatening most of the time.
Many coronaviruses in the animal species are not a risk to humans. Mammals and birds are typical hosts for coronavirus, but the majority of these them can’t infect humans according to history.
Human Coronavirus (HCov)
Generally, human coronavirus infections are not deadly illnesses. They are normally associated as the cause of common cold. Based on historical data for human coronaviruses, most people would contract coronavirus at some point. But it is very unlikely to be severe.
The majority of human coronaviruses cause various respiratory illnesses such as the common cold, pneumonia, and bronchiolitis. Up to 5% to 10% of community-acquired upper respiratory tract infections in adults are because of coronavirus. At times, they also play a role in causing severe respiratory infections in children, adults and those with underlying pulmonary diseases.
Infections normally peak during winter and early spring, but it is present all year round.
At the moment, scientists have identified seven human coronaviruses.
Common Human Coronavirus
HCoV-229E (Alpha coronavirus)
Discovered in 1966, the host for this coronavirus is bats.
HCoV-OC43 (Beta coronavirus)
Discovered in 1967, the host for this coronavirus is cattle.
The two viruses listed above are common causes of the common cold.
HCoV-NL63 (Alpha coronavirus)
The first case of this virus was in the Netherlands in 2004, from a 7-month-old baby. Typical patients of this virus are young children with upper and lower respiratory tract infections. This viral infection is a common worldwide occurrence and it is associated with severe lower respiratory tract infection, croup, and bronchiolitis. The hosts for this virus are palm civets and bats.
There is currently no known effective antiviral therapy for this virus.
Based on human coronavirus historical records, HCoV-HKU1 was the fourth coronavirus discovery. Scientists discovered it in Hong Kong when a 71-year-old man returned to Hong Kong after visiting China in 2005.
Children who had this viral infection suffered from upper or lower respiratory tract infection or both.
The host for this virus is mice.
All four viruses mentioned above (HCoV-229E, HCoV-OC43, HCoV-NL63, HCoV-HKU1) typically cause mild to moderate upper-respiratory tract illnesses, like the common cold. The incubation period for these viruses listed above is normally 3 to 4 days.
SARS (SARS-CoV; Beta Coronavirus)
As mentioned earlier, typically those infected with coronaviruses are unlikely to contract a severe disease. At most, they would have a common cold.
However, this all changed with the introduction of the Severe Acute Respiratory Syndrome disease (SARS). In 2002, SARS was the first human coronavirus to cause severe diseases that led to the death of 774 people. It was first recognized in Guangdong, China, as atypical pneumonia with fever, headache and related symptoms of respiratory illnesses. By 2003, SARS spread across to 28 regions around the world with 8096 infected victims and 774 deaths (9.5% fatality rate).
In 2004, research confirmed masked palm civets were the cause of SARS.
Human transmission for SARS is via infected saliva. After a person is infected, it takes three to ten days before symptoms appear. Symptoms of SARS are similar to the flu: fever, dry cough, respiratory difficulties and the like.
At the moment, no new cases of SARS have been reported and neither is there a cure for this disease.
MERS (MERS-CoV; Beta coronavirus)
In 2012, scientists identified the first case of Middle East Respiratory Syndrome (MERS). The victim was admitted to Erasmus Medical Center in Saudi Arabia. Medical staff named the virus human coronavirus-EMC as a temporary name.
The genetic make-up of the virus is closely related to coronaviruses found in bats. After extensive research, evidence suggests that MERS can also affect camels too.
While the disease was mostly contained around the Arabian Peninsula, MERS was seen in other regions as well. The most notable virus outbreak of MERS outside of the Arabian Peninsula was in South Korea in 2015.
The symptoms of MERS were similar to SARS. However, the fatality rate was much higher -a stark 34%. The symptoms of MERS typically appear 2 to 14 days after exposure. However, most of the time, symptoms appear within 5 to 6 days.
Other than showing similar respiratory illness symptoms similar to SARS, severe complications often developed shortly after that. For many, pneumonia and kidney failure followed soon after. However, some patients observed showed no symptoms at all, despite carrying the disease.
For every 10 people reported to have MERS, 3 to 4 would die.
Most of the victims that passed away already had a pre-existing medical condition that weakened their immune system.
There is currently no vaccine for MERS.
Many of us are now fully aware of COVID-19.
Another disaster is looming over, based on the coronavirus history we’ve just reviewed.
While much is still unknown, there are a few things we know for sure.
COVID-19 is the name of the disease ‘Coronavirus Disease’. Its virus strand, on the other hand, goes by a different label.
The labeling of viruses and diseases undergo different processes for different purposes. The International Committee on Taxonomy of Viruses (ICTV) are the ones responsible for naming viruses. The ICTV names viruses on their genetic mock-ups to help with grouping of viral species.
The disease, however, is named by the World Health Organization (WHO) in the International Classification of Diseases (ICD). The goal is to be simplistic enough in terms of recalling to enable discussion on the disease.
Due to COVID-19’s genetic mockup being genetically related to SARS, the ICTV named it after SARS-CoV. The official virus name is “Severe Acute Respiratory Syndrome Coronavirus 2”, or SARS-CoV-2.
While the origin of COVID-19 is still unknown, many scientists believe that the origin is from bats. In order to trace a virus to its source, scientists must look for clues in the biological make-up.
At the moment, scientists have detected similarities between coronaviruses in bats and COVID-19. However, this particular bat virus does not have the capability to be transferable to humans. Therefore, it is likely that the bat coronavirus infected an intermediary animal that was later transferred to humans.
While we can’t say for sure, which animal was the cause of the new pandemic, pangolins are the likely host. The genetic sequence of coronaviruses isolated from this animal showed a 99% similarity to COVID-19.
Across SARS, MERS, and COVID-19, COVID-19 is by far the worst in terms of total victim count.
The worst part of it all is the fact that this is ongoing and the victim count is increasing every day.
From the looks of it, the situation for COVID-19 is dire, with WHO officially declaring this disease as a pandemic.
On the one hand, people are stockpiling food and supplies at home to prepare for shortages.
On the other hand, we have doctors and other medical entities that are already facing shortages in terms of protective gear.
If you can help yourself prepare for shortages, wouldn’t it be nice to help others as well?