As the global vaccination drive gains impetus and governments are considering immunity passports for people who have had the virus, questions are being asked about coronavirus mutations and immunity levels. Some illnesses only infect a person once, like chickenpox for example, but other viruses, like flu and tetanus, can be caught again. So, can you get the coronavirus twice? Let’s take a deeper look at this question and how it affects public health.
The Science Behind The Covid-19 Virus
What we know about the coronavirus is changing all the time and while there haven’t yet been any peer-reviewed studies on second infections of coronavirus, there have been isolated reports of it happening around the world.
These anecdotal accounts have not been evaluated conclusively either, and scientists are unsure whether they were in fact second infections, or if the patients had not actually fully recovered and cleared the virus after the first infection.
It does ask more questions about immunity, public health and herd immunity and our expectations of vaccinations. In one account, a general practitioner reveals how his patient appeared to have had a second infection of the covid-19 virus. But rather than experiencing a milder infection, as would have been expected after having acquired the antibodies after the first infection, this particular patient had a much worse infection and the general practitioner is surprised by this.
There have been other anecdotal cases where patients have been admitted to the hospital after testing positive, seemingly recovered and then been discharged. A short while later they tested positive for the covid-19 virus again. It is suspected that in some of these cases, the patients had not fully cleared the virus, however, not all facts are known.
Some theories exist on the virus’ dormancy and suggest that the nature of the testing may not paint an accurate picture. Some scientists argue that a throat swab could arguably come back clear after a clinical recovery but that the virus could re-emerge if it found its way into the lungs.
So far it is possible for one part of the respiratory tract to be infected and recover, and for the virus to move into another part of the respiratory tract to cause reinfection – but this is strictly not a second infection.
In order to answer this question accurately, scientists agree that long term studies would need to be conducted into re-exposures. Because we do also know that there is a certain percentage of people who have been infected with the covid-19 virus, recovered, been re-exposed and not become sick a second time.
The reason for this is down to our immune system programming. It’s expected that once the body has been exposed to and reacted to a virus, that it would “remember” the appropriate response the second time around and respond much faster. This is, of course, the principle that the vaccine works on too: it’s designed to elicit an immune response that we expect the body to remember if it encounters the real virus. If you have any questions about the vaccine, speak to your general practitioner.
In the anecdotal examples, it’s not clear whether the patients had underlying health conditions, or what the state of their health was.
Can A Second Infection Be Worse Than A First Infection?
According to experts on public health, this is possible, and due to a very rare process known as ‘antibody-dependent enhancement of disease‘. It occurs with dengue fever but it hasn’t been studied properly with the covid-19 virus yet.
What About Future Mutations Of The Virus?
Experts don’t really know yet but they do agree that anything is possible. One school of thought holds the belief that the covid-19 virus will become seasonal and behave similarly to the flu. This is important for public health because it means that there will be a season for it every year when it will peak, and then taper off again.
This theory is based on current understandings of the other coronaviruses that are in circulation. There are four of them, one of which causes the common cold. These strains, and the flu virus, circulate every year and infect people during their season. It is possible to catch these strains of coronavirus more than once.
How To Stay Safe From A Second Infection?
So can you get the coronavirus twice? It’s better to be safe than sorry. Practising the right safety protocols needs to be continued in the interests of public health as we learn more about the covid-19 virus. If you are concerned about a second infection speak to your general practitioner for more specific tips.
- Avoid unnecessary excursions and travel
- Avoid large crowds and badly ventilated areas
- Wash your hands and sanitise regularly
- Wear a face mask and practice social distancing
If you have concerns about ‘can you get the coronavirus twice’, it’s best to discuss them with a general practitioner. Please contact us for an appointment: (02) 9159 6903.