The signs of COVID-19, the infection caused by the coronavirus, are often mild and are very similar to a cold, flu or chest infection.
Typical symptoms of infection include a fever, a cough, and shortness of breath or difficulty breathing.
These are common complaints at this time of year, so where someone has travelled or who they have come into contact with are important in determining whether they might have coronavirus.
The NHS considers people to be at risk if they have the symptoms above and have recently travelled to mainland China, South Korea, Thailand, Japan, Hong Kong, Taiwan, Singapore, Malaysia, Macau, Vietnam, Cambodia, Laos, Myanmar, or the north of Italy (north of Pisa and Florence).
People who have, in the past two weeks, been to the Hubei province of China, Iran, the South Korean cities of Daegu or Cheongdo in South Korea, or one of 11 quarantined towns in northern Italy are considered to be at risk even if they feel well.