Dr Yousuf Ali Al mulla
At a time when the medical sectors in various countries of the world are struggling to develop the vaccine for coronavirus, some countries have taken a step further by starting an expanded campaign, to test a sample of whole or some population for antibody testing, which helps in determining the overall impact of COVID-19.
However, earlier many people were worried with questions in mind like, can people be infected with coronavirus twice? Can they get the disease again after recovery from the illness? In fact what I could explain here that really it is two ways it could this happen if people I would say re-infected!
The first question would be- is this virus is mutating so quickly that someone could be infected with the virus one day and make immunity and then dramatically the virus change too quickly and can such individual re-infected as the immune system no longer recognises the virus.
The good news is that the virus is not mutating that quickly and we are fortunate, so immune system will recognize it. On other hand, the second reason why people might be re-infected, is they fail to generate the adequate immune response.
The same virus came back few months later and causes the disease all over again, if someone does not generate an immune response. However it looks that it is not the case either! What I mean here, that if someone had the virus, we tick of this person and he won’t hopefully will be sick again, meaning that he won’t catch infection.
So he or they would contribute to the community herd immunity, allowing us for instance to give them an immunological passport and free to return to normal duties or travelling. Interestingly, you see some patient after recovery from COVID-19, after weeks testing positive!
Ideally speaking these test what we use for the virus are remarkably sensitive for viral RNA. Therefore, in the fight against coronavirus, there is still one big unknown! How many people actually contracted it, without showing any symptoms? And because of the urgent need to get ahead of outbreak and preventing more people from dying as well as pushing the businesses to resume, many countries launched a test for their people for antibodies against coronavirus. However the attractiveness of such a test is clear, as the positive result could be a one way ticket to normalcy.
On other hand, we do recognize that those individual who recovered from viral infection, their immune system in response produced antibodies that will recognize the virus if it attacked second time. Definitely it is understandable that most people seeking their antibody test to learn if they were infected already with coronavirus or not, even if they did not show any symptoms.
Of course, here we must ask ourselves do these antibodies in COVID-19 patient do last in the blood. Earlier last May 2020 I did look to the views expressed by World Health Organization, saying there is no evidence that such tests could show that the individual has immunity or is protected from infection again!, but later the organization reframed it and explained that most people with COVID-19 virus will develop an antibody response that will provide a level of protection!
We noticed that countries began testing for the antibodies and moving forward to an accelerated rate due to several reasons, including for instance, to indicate a previous infection for an individual with possible immunity and I think such test is going toward estimating the number of people who have not been infected so far, tracing the possibility of future development of herd immunity.
Obviously, with countries and companies worldwide racing for vaccine , countries will use also such antibody testing to estimate the number of people who will need a vaccine and forecast the possible infection numbers assuming that there might be a future second wave for such pandemic.
In addition, this COVID-19 antibody testing is important for governments to support future decisions to return to work or schools. It is best to consider the immune system in two distinct parts.
The first one is known as innate immunity and is comprehensive response, which can recognize the general molecular patterns that many different pathogens use to attack the body.
Regrettably, in many cases such system is not enough to prevent viral infection and here begins the second stage of the adaptive immune response. Within few weeks, the B cells in the body will have started producing a long –lasting antibody called Ig-G, which is what most tests are looking for. Yet, no one knows how strong these antibodies are in the coronavirus case, but as long as the person produces them in sufficient quantities, most immunologists agree that they have a degree of protection against infection again.
However, what currently I see that if antibody test comes positive, this will result in increase in the possibility of social mixing or interaction with relatives in particular , which can be especially important for elderly people and people belonging to a risk group like diabetes or other illness. Absolutely, antibodies take a relatively long time to appear and will not appear if you have symptoms of the virus last week.
More importantly, studies showed lately that immunity to the emerging coronavirus may not last for more than months and this is also the case for immunity to other viruses such as influenza. At the end, because there is not enough evidence yet, the positive outcome of antibody test does not necessarily mean that you are immune for long time or not contagious and therefore at least for now you cannot ignore the physical distancing, wearing mask and other related recommendation, as a person should always make his own evaluation based on his personal situation and assume his own responsibility toward himself and those he loves.
Dr Yousuf Ali Al Mulla is a physician, medical innovator and educator
