The Dark History Behind COVID-19: Types of Coronaviruses and Outbreak Causes
Published on May 30, 2020
By Dr. Surya Bhagwati
Chief In- House Doctor
BAMS, DHA, DHHCM, DHBTC | 30+ Years of Experience
With the current coronavirus pandemic it helps to understand the background and facts of coronavirus outbreaks. This is especially important because of the vast amount of misinformation from politicians, celebrities, and influencers who have no medical knowledge. Many who try to undermine the seriousness of the problem suggest that this is the 19th coronavirus outbreak because it’s called COVID-19. They then question lockdown measures believing that we’ve already survived 18 such outbreaks! This just reveals their lack of knowledge, as the infection has been termed COVID-19 due to its emergence in late 2019. This highlights the importance of getting COVID-19 information from trusted sources based on medical facts. Here are some facts about coronaviruses and past outbreaks.
The Coronavirus Family
COVID-19 is not the first human infection to be caused by a coronavirus. In fact, the term coronavirus describes a large group of viruses that infects various birds and mammals, also including us. The coronavirus pandemic that we are currently dealing with is just the latest type of coronavirus infection in humans and it first appeared in Wuhan, China, in December 2019 – hence, the name COVID-19.
The coronavirus family was first recognized in 1937, when it was found to cause a type of avian bronchitis that could threaten poultry stocks. Over the next 80 years, researchers found that there were various strains of coronavirus, causing a wide range of infections in rodents, birds, horses, pigs, livestock, and other domesticated animals too. In fact, there are hundreds of coronaviruses, but only a few of these are known to cause infection in humans. Coronaviruses that affect humans were first found in people who suffered from the common cold, during the 1960s. To be precise, 7 types of coronaviruses cause human infection, with 4 resulting in mild cold and flu-like symptoms, while only 3 are threatening. COVID-19 of course, fits into the latter category.
While most coronaviruses do not affect humans, sometimes viruses can jump between species under favorable conditions. This is what happened with some of the more recent coronavirus outbreaks and such diseases are described as zootonic – originating from animals.
Types of Coronaviruses in Humans
As mentioned earlier, there are 7 coronaviruses that cause infection in humans. All of these involve the upper respiratory tract, causing cold and flu symptoms like nasal congestion, coughing, sore throats, fever, and headaches. Occasionally, they cause complications in the lower respiratory tract, but this is more common among infants, aged adults, and those with preexisting conditions or weakened immune system.
Of the 7 human coronaviruses, 4 are regarded as non-threatening as they usually only cause mild symptoms. In fact, most people suffer from at least one of these infections during their lifetime and many recover without the need for medical care. These non-threatening coronaviruses include:
- 229E (alpha coronavirus)
- NL63 (alpha coronavirus)
- OC43 (beta coronavirus)
- HKU1 (beta coronavirus)
There are 3 other coronaviruses that now infect humans and these pose a greater threat. All of these originated as zootonic diseases, jumping to humans only recently. These include:
Better known to most of us as SARS, which is the acronym for Severe Acute Respiratory Syndrome, this disease also emerged in southern China. The first cases were identified in 2002 and it is believed that the SARS-CoV virus originated in bats, then jumping to other animals, before finally infecting humans. The scope of SARS-CoV now pales in comparison to COVID-19, as the epidemic caused just 8,000 infections and 774 deaths across 26 nations. This was only because the outbreak was successfully contained with stringent containment practices including isolation and quarantines. Since the outbreak was contained in mid-2003, the disease hasn’t really surfaced in public. However, a re-emergence is believed to pose a serious public threat.
Like SARS, MERS is an acronym for Middle East Respiratory Syndrome, caused by the MERS-CoV virus. This viral strain first surfaced in Saudi Arabia, in 2012, but its origins were then traced to Jordan. In this case, humans first contracted the virus from infected camels. It then went on transmit from human to human. Since its emergence 8 years ago, the virus has caused infections in 27 countries, although most were restricted to Saudi Arabia. The number of infections stands at roughly 2,400. Outside of Saudi Arabia, the only major outbreak was reported from South Korea, leading to 186 cases and more than 30 deaths. Last year, more than 200 cases were recorded in Europe and global health authorities continue to track the situation to prevent further outbreaks.
The coronavirus that has caused the COVID-19 outbreak is actually known as SARS-CoV-2. It first emerged in Wuhan, China in late 2019. The virus is also believed to be zootonic, with reports suggesting that the virus may have first caused human infection at a wet market in Wuhan. This is by far the deadliest of all the coronavirus infections so far due to the high rate of transmission through social contact and the nature of asymptomatic transmission. The rapid spread of the virus forced much of the world to enforce lockdowns and social distancing measures. Despite these efforts, there have been more than 4 million infections and over 300,000 deaths globally. Without the slew of preventive measures, the toll would be even higher.
Causes & Origins of Recent Coronavirus Outbreaks
It is now the widespread belief that all 3 virus outbreaks (SARS, MERS, and COVID-19) originated from bats. This has been confirmed to an extent by analysis of the 2019-nCoV genome, which points to a shared RNA with a coronavirus that was already known to exist in a specific bat species found in China. While the disease may have originated for bats, it should be noted that bats are not to blame for the infection. If anything, we need to do more to conserve our environment and protect the habitat of other species.
All of these viruses in bats have been around for decades if not centuries, but they did not cause infections in the past. The rise in zoonotic transmissions in recent decades is linked to unrestricted population growth, which puts greater pressure on natural resources, increases deforestation for living space and farmland, and increases contact with wild animals. Wet markets where livestock and wild animals are sold and slaughtered greatly exacerbate the problem with their unhygienic and unsanitary conditions. All of these problems can be linked to our disconnect with nature and a lack of respect for natural resources, the environment, and other species.
This makes Ayurved all the more relevant for us today with its lessons in harmonious living with nature. We can also take a page from Ayurved to better protect ourselves with healthy diet and lifestyle habits, as well as the use of herbs to strengthen immunity. Most importantly, stay informed and don’t succumb to misinformation or rumors
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