SARS-CoV-2 Pandemic

Archive: this article was written in April 2020, in the early months of the pandemic. The figures and scientific understanding described reflect what was known at that time. Retained as a historical record — for current information, see NHS guidance on COVID-19.

On 31 December 2019, Chinese public health authorities reported several cases of acute respiratory syndrome in Wuhan City, Hubei province, to the World Health Organization.

Investigators identified the causative agent as a coronavirus, and a strain not previously seen in humans. The disease was named COVID-19, an abbreviation of coronavirus disease 2019. There was early confusion between the name of the disease and the virus: COVID-19 is the illness, caused by the virus SARS-CoV-2.

Coronaviruses

Two other coronaviruses caused epidemics in the preceding two decades. SARS-CoV emerged in southern China in November 2002 and was recognised as a global threat by March 2003, spreading to 24 countries and causing 8,098 cases and 774 deaths. WHO declared that outbreak over in July 2003.

MERS-CoV was identified in Saudi Arabia in April 2012 and has since been detected in 26 other countries. Between April 2012 and September 2019, 2,494 cases were reported, including 912 deaths.

COVID-19 case numbers rose sharply through early 2020, leading WHO to declare a pandemic on 11 March 2020.

Coronaviruses are a large family of single-stranded RNA viruses, believed to originate in animals before transmitting to humans. SARS-CoV originated in the Himalayan palm civet and MERS-CoV in dromedary camels. The origins of SARS-CoV-2 remain debated.

Structure

Coronaviruses are positive-stranded RNA viruses with a distinctive crown-like appearance under an electron microscope, created by glycoprotein spikes on their surface. This family of viruses is responsible for a meaningful share of acute respiratory infections.

Transmission

The earliest cases were linked to a market in Wuhan, suggesting initial animal-to-human transmission. As the virus spread, human-to-human transmission became the clear driver.

Like influenza, coronaviruses spread largely via respiratory droplets released when coughing and sneezing. This is why public health guidance focused on regular handwashing with soap for at least 20 seconds, covering the mouth and nose when coughing or sneezing, and disposing of tissues promptly.

Transmission from contaminated surfaces was also considered likely at the time. Early laboratory work suggested the virus could persist for up to 24 hours on cardboard and up to three days on plastic and stainless steel. Later research indicated surface transmission plays a considerably smaller role than airborne spread — a good illustration of how understanding evolved after this article was written.

About Rightangled

Rightangled is a UK-registered online pharmacy offering prescription treatments, home blood tests and DNA tests. Our clinical team includes GPhC-registered independent prescribers, with medical oversight from our doctor, Dr Abdullah.

This page is retained as a historical record and should not be used as current health guidance.