The majority - 80 per cent - of coronavirus cases are reported to be mild. However, some underlying heath conditions make you a "high risk" group.
High risk can mean you're more likely to suffer a severe infection of Covid-19, or that you're more likely to catch it in the first place.
This is everything you need to know about the conditions that make you a high-risk group, plus all the latest advice on how to shield yourself from infection.
What underlying conditions make people more likely to catch coronavirus?
As coronavirus is a novel virus, no-one has built up any immunity to it - meaning anyone can become infected, regardless of age, gender or any other factors.
However, evidence suggests that those with weakened immune systems, as with any virus, are more susceptible to becoming infected by coronavirus.
This includes those undergoing cancer treatment, those who are being treated for autoimmune diseases like lupus, Multiple Sclerosis or inflammatory bowel diseases, those with HIV and those having an organ or bone-marrow transplant.
What underlying conditions put people at the highest risk of severe infection?
A report from the World Heath Organisation which studied cases in China said that the underlying conditions which put people at the highest risk of severe disease are hypertension (high blood pressure), diabetes, cardiovascular disease, chronic respiratory disease (such as lung disease or asthma) and cancer.
While patients without comorbid contitions (a medical condition co-occurring with coronavirus) had a crude fatality rate of 1.4 per cent, patients with cardiovascular disease had a fatality rate of 13.2 per cent.
For diabetes this was 9.2 per cent, 8.4 per cent for hypertension, 8.0 per cent for chronic respiratory disease and 7.6 per cent for cancer.
What other conditions or factors make severe infection more likely?
Age is one of the biggest risk factors when it comes to severity of infection, with the highest mortality rates in patients over the age of 80.
It has also been suggested that those who smoke or vape may be more susceptible to catching coronavirus and more likely to contract a severe infection.
Those with eating disorders or any other condition which causes them to lose a large amount of weight may also be more susceptible to catching coronavirus given the condition can cause low-white blood cell counts which weakens the immune system.
What precautions should I take if I have some of these risk factors?
Those at high risk of contracting coronavirus and/or contracting a more severe form of the disease should follow precautions to lower their risk of catching it.
This includes washing your hands regularly and thoroughly, avoiding touching your eyes, nose and mouth and avoiding contact with anyone who is unwell.
Everyone is now being advised to practice social distancing - avoiding all but necessary journeys and contact with others.
The government is issuing guidance by letter to those in the most high risk groups across the UK, advising them to avoid contact with other people and remain inside for 12 weeks beginning from 23 March.
To protect others from becoming unwell, you should also stay at home if you start to feel ill and cover coughs or sneezes with a tissue, and then throw the tissue in the bin.
Coronavirus: the facts
What is coronavirus?
COVID-19 is a respiratory illness that can affect lungs and airways. It is caused by a virus called coronavirus.
What caused coronavirus?
The outbreak started in Wuhan in China in December 2019 and it is thought that the virus, like others of its kind, has come from animals.
How is it spread?
As this is such a new illness, experts still aren’t sure how it is spread. But, similar viruses are spread in cough droplets. Therefore, covering your nose and mouth when sneezing and coughing, and disposing of used tissues straight away is advised. Viruses like coronavirus cannot live outside the body for very long.
What are the symptoms?
The NHS states that the symptoms are: a dry cough, high temperature and shortness of breath - but these symptoms do not necessarily mean you have the illness. Look out for flu-like symptoms, such as aches and pains, nasal congestion, runny nose and a sore throat. It’s important to remember that some people may become infected but won’t develop any symptoms or feel unwell.
What precautions can be taken?
Washing your hands with soap and water thoroughly. The NHS also advises to cover your mouth and nose with a tissue or your sleeve (not your hands) when you cough or sneeze; put used tissues in the bin immediately and try to avoid close contact with people who are unwell. Also avoiding touching eyes, nose and mouth unless your hands are clean.
As of Monday 16 March the government advised that everyone should be observing social distancing - avoiding unnecessary travel and working from home where possible. Anyone with a cough or cold symptoms now needs to self-isolate with their entire household for 14 days.
The government has now instructed bars, restaurants and theatres to close and will review on a ‘month to month’ basis. Schools closed from Friday 20 March for the foreseeable future, and exams have been cancelled.
The over 70s or anyone who is vulnerable or living with an underlying illness are being asked to be extra careful and stay at home to self-isolate. People with serious underlying health conditions will be contacted and strongly advised to undertake "shielding" for 12 weeks.
For more information on government advice, please check their website. https://www.gov.uk/government/topical-events/coronavirus-covid-19-uk-government-response
Should I avoid public places?
The advice now is to avoid public places and any non-essential travel. Travel abroad is also being advised against for the next 30 days at least, and many European countries have closed their borders.
What should I do if I feel unwell?
Don’t go to your GP but instead call NHS 111 or look online at the coronavirus service that can tell you if you need medical help and what to do next. https://111.nhs.uk/covid-19
When to call NHS 111
NHS 111 should be used if you feel unwell with coronavirus symptoms, have been in a country with a high risk of coronavirus in the last 14 days or if you have been in close contact with someone with the virus.
Sources: World Health Organisation and NHS