Cases of Covid-19 first emerged in December 2019, when a mysterious illness was reported in Wuhan, China. The cause of the disease was soon confirmed as a new kind of coronavirus, and the infection has spread to a number of countries around the world.
The most commonly reported symptoms include a fever, dry cough and tiredness, and in mild cases people may get just a runny nose or a sore throat. In the most severe cases, people with the virus can develop difficulty breathing, and may ultimately experience organ failure. Some cases are fatal.
On 11 March, the WHO announced that the outbreak should be considered a pandemic – a term that has no universally agreed definition, but means that multiple countries are seeing sustained transmission between people of an outbreak causing disease or death.
The risk of death has been difficult to calculate, as it relies on accurate numbers of those who have symptoms but survive – and some countries, including the US, have been slow to increase capacity for testing. A small study of people who contracted covid-19 in Wuhan suggests that the risk of death increases with age, and is also higher for those who have diabetes, disease, blood clotting problems, or have shown signs of sepsis.
Read more: https://www.newscientist.com/term/covid-19/#ixzz6HTDRGI3T