The new coronavirus (Covid-19) has spread to nearly every country in the world since it first emerged in China at the beginning of the year. More than 16.5 million people are known to be infected and more than 655,000 deaths have been recorded – including 45,878 in the UK.
What is a coronavirus?
Coronaviruses are a family of viruses that cause disease in animals. Seven, including the new virus, have made the jump to humans, but most just cause cold-like symptoms.
Covid-19 is closely related to severe acute respiratory syndrome (SARS) which swept around the world in 2002 to 2003. That virus infected around 8,000 people and killed about 800 but it soon ran itself out, largely because most of those infected were seriously ill so it was easier to control.
Another coronavirus is Middle East respiratory syndrome (MERS), cases of which have been occurring sporadically since it first emerged in 2012 – there have been around 2,500 cases and nearly 900 deaths.
Covid-19 is different to these two other coronaviruses in that the spectrum of disease is broad, with around 80 per cent of cases leading to a mild infection. There may also be many people carrying the disease and displaying no symptoms, making it even harder to control.
So far, around 20 per cent of Covid-19 cases have been classed as “severe” and the current death rate varies between 0.7 per cent and 3.4 per cent depending on the location and, crucially, access to good hospital care.