Immunity to Covid 19 is a hot topic. Medical Officers and politicians are continually being questioned about testing, vaccines and antibodies. Understanding immunity could help us to emerge from lockdown. We need to identify who has had the virus and no longer at risk of catching or spreading it. As well as tracking people who are infectious and tracing their contacts. With this information, we will be in a far stronger position to return to a new normality.
As the coronavirus is such a new phenomenon, there are many unanswered questions about how to manage it long-term. Research is ongoing.
In this article, we will provide you with up-to-date information about COVID-19 and immunity. The following information is largely taken from the World Health Organisation, BBC Health and other reputable sources.
Is it possible to become immune to COVID-19?
Our immune system is capable of developing antibodies to fight off bugs. It also remembers them for the next time they attack the body.
Unfortunately, as the COVID-19 strain of coronavirus is still so new, it’s not yet known whether our bodies will build up an immunity to the virus.
“We do not know enough about the interaction between the current coronavirus and our immune system. This is to definitely say if we would develop a protective immune memory response,” explains Dr Macciochi.
“And if we do, we don’t know if the memory response is long-lived. Nor do we know whether the virus will mutate and evade that protective memory.”
But there is some good news. People are recovering from COVID-19. This suggests our bodies are capable of an immune response to the virus.
Dr Barnish adds, “We know that the immune system can successfully fight off the COVID-19 virus. Evidence of the role each immune cell type plays is emerging. There are some similarities to the flu virus response.”
The issue stands that, like many viruses, coronavirus can change easily and often. A new version of the virus may have the ability to hide from the immune memory cells. This is why each year we need flu jabs to keep up with these changes.
Can you get Covid-19 more than once?
The immune system’s memory is rather like our own. It remembers some infections clearly but has a habit of forgetting others.
For example, measles is highly memorable – one bout should give life-long immunity. (as the weakened version in the MMR vaccine does).
The new coronavirus has not been around long enough to know how long immunity lasts. But there are six other human coronaviruses that can give a clue.
Four produce the symptoms of the common cold and immunity is short-lived. One Study shows some patients could be re-infected within a year.
“The question is not whether you become immune, it’s how long for. It almost certainly will not last for life” said Prof Paul Hunter, a professor in medicine at the University of East Anglia.
Maria Van Kerkhove in another BBC interview discusses re-infection. This follows reports of many people in South Korea testing negative post infection and then re-testing positive again. She states that they are positive these people were not re-infected. She explains that as part of the healing process post Covid-19. Some people continue to cough up particles within their lungs, for weeks post Covid-19. These particles will still test positive for the virus. However they are not a sign of re-infection, nor is there sufficient infection for them to be contagious.
If I have antibodies am I immune?
Some governments suggest that the detection of antibodies to coronavirus could serve as the basis for an “immunity passport” or “risk-free certificate”.
This is a suggestion that would enable individuals to travel or to return to work assuming that they protect against re-infection. This would be particularly valuable for staff in care homes or hospitals who encounter those at risk of developing severe symptoms.
WHO state that there is currently no evidence that people who have recovered from COVID-19 and have antibodies are immune from a second infection.
While you will find some antibodies in nearly every patient, not all are equal. Neutralising antibodies are the ones that stick to the coronavirus and can stop it infecting other cells.
That is why the World Health Organization says “that cellular immunity [the other part of the adaptive response] may also be critical for recovery”.
Another issue is that just because your antibodies may protect you, it does not mean you cannot still harbour the virus and pass it onto others.
Maria Van Kerkhove also suggests that the WHO believe that the more seriously someone gets the disease, the more antibodies someone produces. Therefore, it is possible that someone who is asymptomatic with Covid19 (and tests positive for the virus), may not produce enough antibiodies to prevent them getting the virus again. Children and adolescents appear to have a different response to the virus and don’t tend to produce antibodies in the same way as adults.
Why is Covid19 experienced at different severity in different people?
Maria Van Kerkhove states that people have different ACE2 receptors in their respiratory tract. The virus uses these receptors to infect the respiratory tract.
Older men seem to have more ACE2 receptors. Different ethnic groups appear to also have a different response to the virus too, however it is not fully known why this is. Young people have a different immune response and so consequently don’t produce antibodies in the same way – therefore antibody tests are less reliable.
As the immune system ages, it becomes less able to overcome the viruses. Experiencing a high load of the virus (such as with healthcare workers) appears to mean the body makes it harder to overcome the virus.
Is testing the answer to getting us out of the COVID-19 crisis?
- A viral test tells you if you have a current infection.
- An antibody test tells you if you had a previous infection
An antibody test may not be able to show if you have a current infection, because it can take 1-3 weeks after infection to make antibodies. We do not know yet if having antibodies to the virus can protect someone from getting the virus again, or how long that protection might last.
The Scottish Government are heavily promoting the importance of viral testing. They state that ‘testing people who have COVID-19 symptoms will enable them to know whether they can resume normal activities because they are negative, or to receive the care and advice they need to help them and their contacts isolate effectively.’
Many countries have successfully used the track and trace method to carefully control the spread of the virus. Until there is a vaccine, or effective cure for the disease, it is the only way to identify and isolate individuals who may be infectious. Hence the Government is looking to follow the lead of others in developing an app to help track and trace potentially contagious individuals and enable the UK to return to a new normality.
Award-winning first aid training tailored to your needs – Please visit our site and learn more about our practical and online courses. It is vital to keep your skills current and refreshed.
It is strongly advised that you attend a fully regulated Practical or Online First Aid course to understand what to do in a medical emergency. Please visit?https://firstaidforlife.org.uk?or call 0208 675 4036 for more information about our courses.
First Aid for Life is a multi-award-winning first aid training provider. Our trainers are highly experienced medical, health and emergency services professionals who will tailor the training to your needs. Courses for groups or individuals at our venue or yours.
First Aid for life provides this information for guidance and it is not in any way a substitute for medical advice. First Aid for Life is not responsible or liable for any diagnosis made, or actions taken based on this information.