On 11 March 2020, the World Health Organisation (WHO) declared the COVID-19 coronavirus a pandemic. This is an important change from its previous classification as an epidemic and shows how the virus has spread very quickly across the world.

An epidemic is the fast spread of a disease that affects lots of people in one particular area – it can be quite a big area – in a short period of time.

A pandemic refers to the worldwide spread of a new disease.

The coronavirus infection emerged in Wuhan, a large city in China, in late December last year – the year 2019. (Hence, the number 19 attached to COVID). At first it was an epidemic, in one area. But now it has become a pandemic.

A coronavirus is a virus that causes disease in animals. In the past seven of these coronaviruses have jumped over to infect humans but most of these only cause mild symptoms similar to a common cold.

The COVID-19 coronavirus seems to have made the transfer from a particular animal to humans in a Chinese live animal market in late 2019. Exotic animals, such as the pangolin, were sold at this market, and that’s where scientists think the disease came from, but they are not absolutely sure.

It’s important to note that the COVID-19 coronavirus is NOT present in the animals and pets around us, so you don’t need to worry about them infecting you!

There have been a few other coronaviruses that have caused considerable disease in people but generally this is rare. You may remember some of the names of these:  Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) are other examples of serious diseases caused by coronaviruses.

SARS was identified in 2002 and spread to around 30 countries. 8,000 cases were reported worldwide, with 774 deaths (so about 10% of people who caught SARS died). This outbreak subsided, and no new cases have been identified since 2004.

MERS was first reported in September 2012 in Saudi Arabia. There have been nearly 2,500 infections (with at least 850 related deaths) in 27 countries. About 35% of people who get MERS die, but recently the number of cases has declined sharply.

On 31 December 2019, China alerted the WHO of several flu-like cases in Wuhan, and it was seen as an epidemic. However, since then things have changed quickly.

In a statement, WHO director-general Dr Tedros Adhanom Ghebreyesus said: “WHO has been assessing this outbreak around the clock and we are deeply concerned both by the alarming levels of spread and severity and by the alarming levels of inaction.

“We have therefore made the assessment that COVID-19 can be characterised as a pandemic.

“We have never before seen a pandemic sparked by a coronavirus. This is the first pandemic caused by a coronavirus. And we have never before seen a pandemic that can be controlled, at the same time.”

The new coronavirus (Covid-19) is spreading fast. At the point of writing (mid-March 2020), more than 300,000 people are known to have been infected and over 14,000 deaths have been recorded. While the outbreak started in China, today most of the cases and fatalities (deaths) are now outside the country, and the virus is spreading internationally. As of 22 March, South Africa has 274 confirmed cases, but the WHO has said that Africa needs to ‘wake up and prepare for the worst’.

As you are reading this, how many cases more are there now?