Can you get coronavirus twice? What happens to the body after a Covid-19 infection – and if the immune response lasts
Prime Minister Boris Johsnon is now self-isolating after being in contact with an MP who has tested positive for Covid-19
Strict lockdown restrictions still remain in place across the UK as part of efforts to drive Covid-19 infections down in as winter approaches.
The pace of the virus has caused increasing concerns about further spread, and as more people are diagnosed, it has prompted the question if it is possible to contract the virus more than once.
Can you get coronavirus twice?
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 fears that the virus could be contracted more than once after reports of reinfection.
A woman in her 40s in Osaka, Japan, tested positive for Covid-19 for a second time. She 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 5 March, stating more discharged patients had been readmitted after falling ill a second time.
More recently, Hong Kong scientists have reported that a healthy man in his 30s has become reinfected with coronavirus four and a half months after his first diagnosis.
Scientists said the genome sequencing shows that the two strains of the virus are "clearly different", making it the world's first proven case of reinfection. However, the World Health Organization has warned that conclusions cqannot be made on the basis of just one patient.
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, those who have been infected with the virus develop an immune response as their bodies fight it off, helping to protect them against it in the future.
It has been found that the most seriously ill patients develop the strongest immune response, but it is still unclear as to how strong this immunity is, or how long it lasts.
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) explains, “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.”
PM self-isolating again
Prime Minister Boris Johnson is currently self-isolating for a second time after being in contact with an MP who has since tested positive for Covid-19.
Mr Johnson, who was admitted to intensive care with coronavirus in April, attended a 35-minute meeting on Thursday (12 November) alongside MP for Ashfield, Lee Anderson, who received a positive test result on Sunday (15 November).
A Downing Street spokesman said the PM was “well” and does not have any coronavirus symptoms. He is continuing his work from Downing Street while in isolation.
In a statement on Twitter, Mr Johnson said he is feeling great and is “bursting with antibodies”, but will follow the rules on self-isolating to prevent any further spead.
He said: “Hi folks, the good news is that NHS Test and Trace is working ever-more efficiently, but the bad news is that they’ve pinged me and I’ve got to self isolate because someone I was in contact with a few days ago has developed Covid.
“It doesn’t matter that we were all doing social distancing, it doesn’t matter that I’m fit as a butcher’s dog, feel great – so many people do in my circumstances.
“And actually it doesn’t matter that I’ve had the disease and I’m bursting with antibodies. We’ve got to interrupt the spread of the disease and one of the ways we can do that now is by self-isolating for 14 days when contacted by Test and Trace.”