Indicator – Economy – Do we mean the same when we talk about herd immunity?

There is a disagreement among virologists over whether the SARS-CoV-2 coronavirus might develop frequent flushing immunity against boredom. However, the concept plays a major role in landing a pandemic, as it determines an additional defense path.

We have read and heard the opinions of local and foreign experts, on the basis of which we try to give the clearest possible picture of whether societal immunity can be achieved in Hungary.

Among the well-known immunologists, biologists, infectologists and veterinarians, we have heard Bella Merkelly, Janus Slavic and possibly Miklos Rosvay most often talk about how many people need to be vaccinated in order to develop herd immunity against Covid. Janus Slavik talked about the 5-6 million threshold this week, Bella Merkeli and Rosvay said at least 5 million earlier.

One of the most popular medical journals, The Lancet, comes out in late April In the article Citing a British study of nearly 20,000 samples, he wrote that whether herd immunity is available for Covid is already being discussed, but if it is available, epidemiologists generally believe it requires 70 percent vaccination and / or transmission of the population. If natural cross-infection is not counted, the thesis is that 100 percent of the population should be vaccinated with either one or 80 percent with two vaccines.

In contrast, O Mjong Don, chair of South Korea’s Clinical Committee for Disease Control, explicitly argued in early May that even vaccination of 70 percent of the population may be low to protect the community and herd immunity is unlikely to be achieved.

There are several reasons for this. Nature, the world’s leading science journal, recently released Five Points Summed up these:

• According to one of them, it is not yet possible to confirm with absolute certainty that vaccines will protect us from transmitting infection (transmission). There has been generous news about mRNA-based vaccines in this regard, but it requires a longer investigation to obtain similar vaccines from other vaccines.
• The development of community immunity is also hampered by the fact that global vaccine distribution is uneven: many ampoules have not even reached many developing countries, so the virus can spread freely.
• It can also be a problem that as the virus spreads, it can change constantly, and new variants also change the herd immunity threshold.
• Also of concern is that we do not know how long the vaccine will protect – both Pfizer and Moderna have been tested in this regard, indicating high antibody production for at least half a year.
• Finally, it is also important for people to act responsibly, move in contact after vaccination, wear a mask, and maintain distance when needed.

Interestingly, some virologists and immunologists explicitly hate the term herd immunity and use the term herd protection rather than herd immunity, because the phrase “more vaccination protects the smaller, unvaccinated group” does not cover reality, but rather relates to people who get a vaccine that reduces the risk. Confronting those with weaker pathogen bodies.

Endemic nyájimmunitás

With vaccination of 60-70 percent of a community this can be achieved, but if it is done, it depends on many other factors as to whether community immunity can be established.

– We were told this by a well-known Hungarian virologist, but he immediately added: First of all, the concept itself must be clarified. Textbook herd immunity means that vaccines protect the unvaccinated, but there is no scientific evidence of the potency of granite in Covid, because, as Nature writes, we do not know to what extent the vaccine is transmitted and transmitted through vaccines. This will require looking at the results of all vaccines used and how inhibitory they are for this particular transmission.

Transmission is key when examining herd immunity

This is a result of the increasingly strong scientific view that the potentially fatal or dangerous disease caused by the Coronavirus can be prevented by vaccines, thus reducing the virus to a endemic effect. This, in turn, may be accompanied by the fact that the Coronavirus, as in the case of seasonal influenza, may need a new vaccination every year to prevent hospitals from filling up again. Of course, this depends on how long and how effective the vaccine protection is

Back to herd immunity itself: Merkely, Slavik, Rusvai and other Hungarian experts think about endemic herd immunity when talking about achieving community immunity. An epidemic means that the pathogen is constantly present in a particular geographical area, but the number of reproduction (infection) can be reduced to such an extent that it does not cause mass diseases in the area or a global epidemic like the current epidemic, i.e. a pandemic. If the three aforementioned professionals (and the others who occasionally speak) refer to endemic herd immunity in their data, that means that vaccination of 60-70 percent is sufficient to reduce the epidemic and keep the vaccine under control. Not to the immunity of the aforementioned herd of books, that is, to the gradual disappearance and elimination of the pathogen.

Eradication can happen if vaccines prevent transmission, so we cannot transmit the virus to each other, in mirror translation, this is sterile immunity. In this case, in the current case of infection, the virus subsides with the appearance of certain symptoms, the chain of infection is broken, and the pathogen disappears.

So far, Covid has not been pushed back globally, and the number of new infections daily continues to rise in some regions of Asia and South America. This, in turn, may have an impact on the development of the viral situation in Hungary, and it is sufficient to think about an Indian mutation that has already appeared in neighboring countries and is more contagious than before. The longer the virus survives, the more likely the mutations will develop, the greater their ability to reproduce, and this can constantly change the herd immunity threshold.

So we need to be prepared to have endemic herd immunity over time, which means SARS-CoV-2 stays with us, can emerge as endemic like influenza, and can be controlled with seasonal vaccination. Further studies will decide who should be vaccinated against anyway.

(Cover photo: People wearing protective masks due to the Coronavirus epidemic in central Madrid, Spain, on May 8, 2021. Photo: Marcos Del Mazo / Light Rocket / Getty Images)