Covid survivors protected from reinfection for five months, study shows
It has been one of the great unanswered questions of the Covid-19 pandemic - does having the virus give any immunity from catching it again? A new study involving hundreds of hospital staff in Hull shows it does. Simon Bristow reports
Hundreds of staff at Hull’s hospitals have played a crucial role in a landmark scientific study which shows people who have had Covid-19 are protected from catching it again for at least five months after contracting the virus.
Staff at Hull University Teaching Hospitals NHS Trust took part in the SIREN study, undertaken by Public Health England (PHE) to see if healthcare workers who had already contracted the virus had any immunity to future infection.
In its first report, produced today, PHE has revealed:
Antibodies from past Covid-19 infection provide people who have already had the virus with 83 per cent protection against reinfection for at least five months;
Reinfections were rare with just 44 potential reinfections in the study of 6,614 people who had antibodies after contracting the virus earlier.
However, early evidence suggests a small number of people with antibodies may still be able to carry and transmit Covid-19; underlining the need for people to follow national guidance to stay at home, and the rules of “hands, face, space”, whether they have had the infection or not, the trust said.
The research nonetheless begins to answer one of the key questions that has dogged scientists since the pandemic began - whether having the virus offers any protection from catching it again.
Phillipa Burns, higher specialist scientific trainee clinical scientist, led the SIREN study in Hull with microbiology consultant Dr Kavitha Gajee.
Speaking exclusively to The Hull Story, Mrs Burns said: “It’s wonderful news and the first major study that’s looked at the protection for healthcare workers.
“It was designed to see if people who’ve got a high level of occupational exposure to the virus, and that’s healthcare workers, to see whether they would have any ongoing protection.
“I’m immensely proud to have been able to lead this piece of research, and to know it’s going to make a difference and provide reassurance to healthcare workers, when at the moment we are all feeling quite vulnerable.
“This will be a boost for so many people because there were so many who had this infection in the first wave and are so worried about having it again. To be able to give reassurance - it’s not definitive but there is a high level of protection - is phenomenal.”
‘IMMENSELY PROUD’: Phillipa Burns, who led the study in Hull
The research involved 550 staff at Hull Royal Infirmary and Castle Hill Hospital - a much higher proportion than from most of the other trusts taking part.
Mrs Burns also praised the “phenomenal” work of research nurse Gemma Walker for helping to deliver such a high participation rate.
Those taking part in the study in Hull ranged from frontline ICU staff to porters, receptionists, and others in non-clinical roles who all have contact with patients.
She added: “The findings are really encouraging and it’s fantastic that staff working on the frontline during the pandemic have contributed so much to our understanding of this terrible disease and how it works.
“By taking part in this major study, our staff are playing a huge role in determining our future response to the virus.”
Those taking part have been having nose and throat swabs every fortnight, and blood tests every month.
Public Health England has been regularly testing tens of thousands of healthcare workers across the UK since August for new Covid-19 infections as well as the presence of antibodies, which suggest people have been infected before.
However, the first report provides no evidence towards the antibody or other immune responses from Covid-19 vaccines, and those involved said no conclusion should be drawn on their effectiveness. The SIREN study will consider vaccine responses later this year.
If you value the content we produce then please consider becoming a Patron of The Hull Story. For just £2.50 a month you can help support the continued operation and development of this independent journalism project dedicated to Hull.
PHE scientists working on the study have concluded naturally acquired immunity as a result of past infections provides 83 per cent protection against reinfection, compared to people who have not had the disease before. This appears to last at least for five months from first becoming sick.
While the SIREN study will continue to assess whether protection may last for longer, this means people who contracted the disease in the first wave may now be vulnerable to catching it again.
Professor Susan Hopkins, senior medical advisor at Public Health England, and the SIREN study lead, said: “This study has given us the clearest picture to date of the nature of antibody protection against Covid-19 but it is critical people do not misunderstand these early findings.
“We now know that most of those who have had the virus, and developed antibodies, are protected from reinfection but this is not total and we do not yet know how long protection lasts. Crucially, we believe people may still be able to pass the virus on.
“This means even if you believe you already had the disease and are protected, you can be reassured it is highly unlikely you will develop severe infections, but there is still a risk that you could acquire an infection and transmit to others. Now more than ever, it is vital we all stay at home to protect our health service and save lives.”
She added: “We are immensely grateful to our colleagues in the NHS for giving up their time to volunteer and whose continued participation at a time of great stress is making this research possible.”