COVID-19 Basics
COVID-19 Basics
What is coronavirus?
The COVID-19 virus is a new pathogen that is highly contagious, can spread quickly, and must be considered capable of causing enormous health, economic and societal impacts in any setting.
What is coronavirus disease 2019 (COVID-19)?
Coronaviruses (CoV) are a large family of viruses that cause illness ranging from the common cold to more severe diseases such as Middle East Respiratory Syndrome (MERS-CoV) and Severe Acute Respiratory Syndrome (SARS-CoV).
A novel coronavirus (nCoV) is a new strain, which has now been termed SARS-CoV-2 that has not been previously identified in humans. COVID-19 is short for CoronaVirus Disease-19, which is a respiratory illness caused by SARS-CoV-2. It is a highly contagious disease that can spread from person to person rapidly.
Why is the disease being called Coronavirus, COVID-19?
On February 11, 2020 the World Health Organization announced an official name for the disease that is causing the 2019 novel coronavirus outbreak, first identified in Wuhan China. The new name of this disease is coronavirus disease 2019, abbreviated as COVID-19. In COVID-19, ‘CO’ stands for ‘corona,’ ‘VI’ for ‘virus,’ and ‘D’ for disease. Formerly, this disease was referred to as “2019 novel coronavirus” or “2019-nCoV”. There are many types of human coronaviruses including some that commonly cause mild upper-respiratory tract illnesses.
History of Coronavirus
Coronaviruses are a big family of different viruses. Some of them cause the common cold in people. Others infect animals, including bats, camels, and cattle. But how did SARS-CoV-2, the new coronavirus that causes COVID-19, come into being?
Here’s what we know about the virus that was first detected in Wuhan, China, in late 2019 and has set off a global pandemic.
Where did the coronavirus come from?
Experts say SARS-CoV-2 originated in bats. That’s also how the coronaviruses behind Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS) got started.
SARS-CoV-2 made the jump to humans at one of Wuhan’s open-air “wet markets.” They’re where customers buy fresh meat and fish, including animals that are killed on the spot.
Some wet markets sell wild or banned species like cobras, wild boars, and raccoon dogs. Crowded conditions can let viruses from different animals swap genes. Sometimes the virus changes so much it can start to infect and spread among people.
Still, the Wuhan market didn’t sell bats at the time of the outbreak. That’s why early suspicion also fell on pangolins, also called scaly anteaters, which are sold illegally in some markets in China. Some coronaviruses that infect pangolins are similar to SARS-CoV-2.
As SARS-CoV-2 spread both inside and outside China, it infected people who have had no direct contact with animals. That meant the virus is transmitted from one human to another. It’s now spreading in the U.S. and around the globe, meaning that people are unwittingly catching and passing on the coronavirus. This growing worldwide transmission is what a pandemic is now.
Coronavirus Evolution
Scientists first identified a human coronavirus in 1965. It caused a common cold. Later that decade, researchers found a group of similar human and animal viruses and named them after their crown-like appearance.
Seven coronaviruses can infect humans. The one that causes SARS emerged in southern China in 2002 and quickly spread to 28 other countries. More than 8,000 people were infected by July 2003, and 774 died. A small outbreak in 2004 involved only four more cases. This coronavirus causes fever, headache, and respiratory problems such as cough and shortness of breath.
MERS started in Saudi Arabia in 2012. Almost all of the nearly 2,500 cases have been in people who live in or travel to the Middle East. This coronavirus is less contagious than its SARS cousin but more deadly, killing 858 people. It has the same respiratory symptoms but can also cause kidney failure.
The Outbreak
As of 15th May 2020, a cumulative total of 4,527,811 COVID-19 cases have been reported all over the world with over 300,000 deaths
Who is at the highest risk?
COVID-19 is a new disease and there is limited information regarding risk factors for severe illness. Based on currently available information and clinical expertise, older adults and people of any age who have serious underlying medical conditions might be at higher risk for severe illness from COVID-19.
Sex:
| Share of total deaths (%) | |
| Males | 61.8% |
| Females | 38.2% |
Age:
| Share of total deaths (%) | |
| 45-64 years old | 3.7% |
| 65-74 years old | 6.5% |
| 75+ years | 14.3% |
Pre-existing Medical Conditions:
Patients who reported no pre-existing (“comorbid”) medical conditions had a case fatality rate of 0.9%. Pre-existing illnesses that put patients at higher risk of dying from a COVID-19 infection are:
| Pre-existing Condition | Death Rate |
| Cardiovascular disease | 13.2% |
| Diabetes | 9.2% |
| Chronic respiratory disease | 8.0% |
| Hypertension | 8.4% |
| Cancer | 7.6% |
| No pre-existing conditions | 0.9% |
Routes of Transmission
Person-to-person spread: The virus is thought to spread mainly from person-to-person
- Between people who are in close contact with one another (within about 3 feet)
- Through respiratory droplets produced when an infected person coughs or sneezes
These droplets can land in the mouths or noses of people who are nearby or possibly be inhaled into the lungs.
Spread from contact with infected surfaces or objects: It may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes.
