Questions have been raised as to whether it is possible to contract coronavirus more than once.

The current outbreak of coronavirus - also known as Covid-19 - has now been declared a global pandemic by the World Health Organisation (WHO).

So far, the virus has reached more than 120 countries, with Europe currently at the epicentre of the outbreak, which originated in China. The pace of the virus has caused increasing concerns about further spread.

Can you get coronavirus twice?

Since coronavirus first emerged in China - with the first suspected cases reported on December 31, 2019 in Wuhan - the virus has killed more than 6,500 people worldwide.

The Covid-19 strain originated in Wuhan City, Hubei Province - the largest city in central China - and is in the same family as SARS and MERS (Middle East respiratory syndrome).

Most people get infected with these viruses at some point during their lives, although they usually only last for a short period of time.

However, there are now fears that the virus could be contracted more than once, after a woman in her 40s in Osaka, Japan, tested positive for Covid-19 for a second time.

The woman was first diagnosed with the virus in late January and was later discharged from hospital on 1 February, but has since been reinfected.

Philip Tierno Jr, professor of microbiology and pathology at New York University, told The Express: “Once you have the infection, it could remain dormant and with minimal symptoms. And then you can get an exacerbation if it finds its way into the lungs.”

A professor of emerging infectious diseases at Duke-NUS Medical School in Singapore, Eng Eong Ooi, told USA Today that it is still too soon to know how long people may be safe from the virus, even after their body has fought it off.

He said: “Inflammation appears to be a cause of severe Covid-19. It also helps in the development of immunity. Any conclusion will be premature, I fear. We will need studies.”

Second positive tests of coronavirus have also been reported in China, with Shanghai-based news portal The Paper reporting that one of Wuhan’s makeshift health facilities had issued an emergency notice on March 5, stating more discharged patients had been readmitted after falling ill a second time.

Are you immune to coronavirus after you get it?

Much like the flu can mutate, it is possible that coronavirus can do the same, meaning it would make someone who has already contracted the virus susceptible to contract it a second time.

However, Dr Stephen Gluckman, an infectious diseases physician at Penn Medicine, told The Express that it seems likely that having the disease once results in immunity in most individuals, as is the case with other coronaviruses.

He said: “Coronaviruses aren’t new, they’ve been around for a long, long time and many species - not just humans - get them. So we know a fair amount about coronaviruses in general.

“For the most part, the feeling is once you’ve had a specific coronavirus, you are immune. We don’t have enough data to say that with this coronavirus, but it is likely.”

If this proves to be the case, people who initially recovered from the virus are more likely to relapse, rather than get reinfected.

However, that doesn’t mean it is not possible to contract the virus again, as the Centers for Disease Control and Prevention (CDC) explained: “The immune response to Covid-19 is not yet understood.

“Patients with MERS-CoV infection are unlikely to be reinfected shortly after they recover, but it is not yet known whether similar immune protection will be observed for patients with Covid-19.”

Coronavirus: the facts by the World Health Organisation and the NHS

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.

Should I avoid public places?

Most people who feel well can continue to go to work, school and public places and should only stay at home and self isolate if advised by a medical professional or the coronavirus service.

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.

When to call NHS 111