Coronavirus symptoms: What are they and how do I protect myself?
Coronavirus has claimed nearly 70,000 lives. Hundreds of thousands of people have been infected around the world.
Among them is UK Prime Minister Boris Johnson, who was admitted to hospital in London on Sunday 5 April as a precautionary measure because of "persistent symptoms" including a temperature.
He has since been moved into an intensive care bed.
What happens in intensive care?
Intensive care units (ICUs) are specialist hospital wards that provide treatment and monitoring for people who are very ill.
They're staffed with specially trained healthcare professionals and contain sophisticated monitoring equipment. There will normally be one nurse for every one or two patients.
The prime minister was moved to an ICU ward at St Thomas's Hospital after doctors judged that his condition had worsened. Mr Johnson is said to be conscious and the move has been described as "a precaution", should he need ventilation treatment to help with his breathing.
Coronavirus patients in ICUs will get oxygen support and there are different ways of doing this. This can involve using a facemask, or a tube in the nose.
The most invasive way - for the most seriously ill patients - is ventilation where air, with increased levels of oxygen, is pushed into the lungs mechanically via a tube in the mouth, nose or through a small cut in the throat.
Patients are given medication to relax the respiratory muscles so their breathing can be fully regulated by the machine.
What are the coronavirus symptoms?
Coronavirus infects the lungs. The two main symptoms are a fever and a dry cough, which can sometimes lead to breathing problems.
The cough to look out for is a new, continuous cough. This means coughing a lot for more than an hour, or having three or more coughing episodes in 24 hours. (If you usually have a cough, it may be worse than usual).
You have a fever if your temperature is above 37.8C. This can make you feel warm, cold or shivery.
It takes five days on average to start showing the symptoms, but some people will get symptoms much later than this. The World Health Organization (WHO) says the incubation period lasts up to 14 days.
A sore throat, headache and diarrhoea have also been reported in some cases and a loss of smell and taste may also be a symptom. But these symptoms aren't specific to this coronavirus.
When do people need to go to hospital?
The majority of people with coronavirus will recover after some bed rest and pain relief (such as paracetamol).
The main reason people need hospital treatment is difficulty breathing.
Doctors may scan the lungs to see how badly they have been affected and give other support, such as oxygen or ventilation, if needed.
However, people should not go to A&E if they are concerned. In the UK, the NHS 111 website will guide you through what you need to do.
If you are so breathless that you are unable to speak more than a few words then you will be told to call 999 as this is a medical emergency.
If you become so ill that you've stopped doing all of your usual daily activities then it will advise speaking to nurse by dialling NHS 111.
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What should I do if I have mild symptoms?
Patients with mild symptoms should self-isolate at home for at least seven days, according to Public Health England.
People are being advised not to ring NHS 111 to report their symptoms unless they are worried. They should also not go to their GP, or A&E.
If you have come into contact with somebody who may be infected, you may be told to self-isolate.
Other countries have introduced their own measures. For example, the US Centers for Disease Control and Prevention advises people showing symptoms to call their healthcare provider, and those who are mildly ill to self-isolate.
The World Health Organization has also issued advice for the public.
How deadly is coronavirus?
The proportion dying from the disease appears low (between 1% and 2%) - but the figures are unreliable.
Thousands are being treated but may go on to die - so the death rate could be higher. But it may also be lower if lots of mild cases are unreported.
A World Health Organization examination of data from 56,000 patients suggests:
- 6% become critically ill - lung failure, septic shock, organ failure and risk of death
- 14% develop severe symptoms - difficulty breathing and shortness of breath
- 80% develop mild symptoms - fever and cough and some may have pneumonia
Older people, and those with pre-existing medical conditions (such as asthma, diabetes, heart disease, high blood pressure), are more likely to become severely ill. The data from China also suggests that men are at slightly higher risk of dying from the virus than women.
Treatment relies on keeping the patient's body going, including breathing support, until their immune system can fight off the virus. Work to develop a vaccine is under way.
What do I need to know about the coronavirus?
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How do I protect myself?
The best thing is regular and thorough hand washing, preferably with soap and water.
Coronavirus spreads when an infected person coughs small droplets - packed with the virus - into the air. These can be breathed in, or cause an infection if you touch a surface they have landed on, then your eyes, nose or mouth.
So, coughing and sneezing into tissues, not touching your face with unwashed hands, and avoiding close contact with infected people are important for limiting the spread.
Face masks do not provide effective protection, according to medical experts.
However, the World Health Organization (WHO) is currently looking at whether the public might benefit from using face masks.
This follows a study suggesting that the virus can travel further in coughs and sneezes than previously thought.
People will be most infectious when they have symptoms, but there have been suggestions some can spread the virus even before they are sick.
The early symptoms can easily be confused with other winter bugs including colds and flu.
Who gets tested and how does it work?
In its latest advice, Public Health England (PHE) has said those who are self-isolating with mild symptoms will not be tested.
If you need testing in the UK results may be available on the same day, but you may be asked to stay at home and self-isolate. while you wait.
How fast is it spreading?
Tens of thousands of new cases are being reported worldwide each day. However, it is thought health agencies may be unaware of many cases.
After starting in China, coronavirus is now spreading fast in many other countries.
It took 67 days from the first reported case to reach the first 100,000 cases, 11 days for the second 100,000 cases and just four days for the third 100,000 cases.
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