How much do we already know about the sars-cov-2 virus?
We know the virus pretty well. However, much more difficult issues remain unresolved, e.g. why it sometimes causes a more severe form and why a milder form of the disease. Also, we do not know those things that will appear in just a few months, e.g. what are the permanent consequences of the infection or how long the immunity may last. We will get the answer only when we can follow the patients for a long time, ie only for a year or similar. Unfortunately, research to date has shown that the amount of antibodies in patients begins to decline in a matter of weeks to months, which means that protection in a natural way is unlikely to be long-lasting.
How far are we in detecting the virus? How far have we progressed since the beginning of the year?
From the very beginning, we had the best possible tests for microbiological diagnostics, ie molecular tests (PCR). These are very sensitive and very specific. This means that they detect extremely small amounts of the virus and distinguish very well between the new coronavirus and the old coronavirus, which are also present in our population. These are also not 100% safe, but they are the best that are currently available.
There are currently more than 800 different tests on the market. Progress is mainly seen in the arrival of the second type of tests, these are antigen tests, also known as rapid tests. In them, we do not detect the presence of the virus by multiplying the viral genes that may be present in the sample, but we use artificially made antibodies and use them to look for viral particles in the patient. The advantage of these tests is mainly the speed, because the result is known in a few minutes. However, at the expense of speed, reliability is lost.
Can these quick tests still be an appropriate solution to facilitate the organization of work, for example in hospitals or companies?
Only in part, for example in hospitals, because they have the knowledge of the proper use of such a test; especially the risks posed by such use. What other organizations do not have this knowledge. Therefore, it would be pointless and wrong to, say, large jobs start routinely using these tests.
What about the different viral strains? What is circulating in Slovenia and what else, are they otherwise dangerous?
Five genomes are known for Slovenia, each different. If we imagine the virus genome as a sequence of 30,000 letters, then different in this case means that each of them had six to seven different letters. These specific small changes are not currently associated with a different hazard or infection. However, a change in the virus was discovered around the world, where part of the genome was lost. If we stick to the previous comparison, a lost part about 400 letters long, and for these viruses, scientists have shown that they are associated with a milder form of the disease in humans.
Changes in the viral genome are random, so it is not possible to predict in which direction its development will take place in a particular geographical area. Many similar viruses are circulating in Europe and we can not say that one form is more dangerous than the other, because we have very little data on how these changes found in the genome affect patients.
Somehow, now it seems that the mortality of covid-19 is lower. Is the virus no longer as strong as it was at the beginning of the year?
The virus has also spread to a population with a lower mortality rate, so overall mortality has also declined. However, as the number of cases increases, so does the number of seriously ill and dead, which carries a heavy burden on the health system. Also, with the increase in the number of cases, the possibility of continuing the transmission increases and thus the epidemic, and the possibility of its introduction in vulnerable groups increases.
Has a drug or vaccine been discovered, the only solution to prevent the spread of the virus has been stopped in public life?
As long as the virus is spreading globally as it is now, it does not help if only one region or one country closes completely, as it is not possible to prevent an outside intrusion as soon as the country reopens. So now it is not possible to stop the virus completely, but we need to reduce the transmission as much as possible. In environments where there are multiple viruses, transmission needs to be reduced drastically, and ongoing action is needed to address this. However, when the frequency of the virus in a particular environment decreases again, life can return to normal. I think in the second wave, we will all learn that these simple measures can actually be very effective.
What does the arrival of autumn and winter mean for the spread of the virus?
Just as summer is a time of gastrointestinal infections, so winter is a time of respiratory infections. Therefore, autumn-winter weather is also more favorable for the spread of the new coronavirus. Partly because cold weather lowers our mucous membrane defense mechanisms, we also have less vitamin D, while providing better resistance to the virus in the environment. The spread of the virus is also easier because we spend more time indoors in the winter. I expect that the situation in our country will worsen during the upcoming winter, and in the summer of next year there will be a slowdown again, as it was this summer.
So, the end of the epidemic is not expected soon?
The epidemic will surely end, but unfortunately not in two months. History teaches us that there will probably be another wave next fall, and then the new coronavirus will slowly begin to disappear from the headlines and begin to follow us normally. For viruses that cause respiratory infections, it is a natural way to slowly get used to each other and begin to coexist.
The problem with the new coronavirus is that it is not yet known to us. For example, the flu virus has been with us for decades and we are used to it, so there are no such dimensions. Our immune system has a memory and the flu is remembered, so if a hundred people came in contact with the flu, less than half would get sick. If these same 100 people come in contact with the new coronavirus, more than three-quarters of them will get sick. And that is the difference. Even if influenza and covid-19 have the same percentage of more severe disease courses, the difference in the number of more severe patients is huge.
Can the next Covid-20 come?
Covid-20 or a new form of influenza may appear and the next new pathogen may be even more dangerous. In fact, we are now lucky that the Covid-19 has arrived, which is spreading extremely fast, but is still relatively mild. For example, we could face a form of coronavirus that would spread like covid-19, but it would be much more lethal.
Mankind has faced diseases throughout history, and from this point of view, the current epidemic is not unusual, and recently such phenomena have only spread better as a result of globalization. We are also lucky due to the fact that protection against the new coronavirus is relatively simple – hand washing, distance, ventilation and protective masks.