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The advent of a new extremely contagious virus variant has made the prospect of overburdening hospitals severely ill with COVID-19 real again. Despite the third dose of the vaccine, the number of those infected continues to rise. The omicron with its 50 mutations has made the currently administered vaccines in fact less and less effective. Israel even made a decision to give high-risk people (mainly the elderly and immunodeficient people) another, fourth dose. However, American experts are not convinced that the world should go this way. Giving consecutive doses every six months seems unrealistic. – It’s time for a new strategy to fight the pandemic – experts say in an interview with The New York Times.
Strengthen protection against omicron and other virus variants
Booster vaccines are not unusual in immunology. This is the case, for example, with the injections against whooping cough and diphtheria, with the annual flu shots recommended being a prime example. However, a fourth dose of the same “old” COVID-19 vaccine does not seem to be the best solution to experts (except for people with a weakened immune system, who may benefit from subsequent doses of the vaccine).
Boosters increase antibody levels and help protect against COVID-19, thereby reducing pressure on the healthcare system by temporarily slowing the spread of the virus. And here the experts agree – we should all take the third dose. However, there is no such certainty about the fourth dose.
The injections bring about a temporary increase in the level of antibodies, but unfortunately this does not last long. As time passes, the concentration of neutralizing antibodies decreases, moreover, even the third dose does not always protect against infection with the omicron, which has “learned” to bypass the body’s immune defenses.
Speaking to the daily Shane Crotty, a virologist at the La Jolla Institute of Immunology in California, states that – despite the high levels of anti-COVID-19 antibodies seen after the third dose – it will now be very difficult to contain the virus for longer. What is needed is a vaccine that targets a specific virus variant, ie the omicron, and not the “classic” SARS-CoV-2.
– There is no point in continuing to reinforce against a variant that has already passed. With a fourth dose of vaccine, I would definitely wait for a vaccine that targets the omicron, said Ali Ellebedy, an immunologist at Washington University in St. Louis. Pfizer, Moderna and Johnson & Johnson are now testing redesigned vaccines with the omicron in mind.
A change of strategy is needed if vaccines are to increase resistance to omicron and future virus variants. Experts believe that inhaled or oral preparations could be used as enhancers for an already administered COVID-19 vaccine. Currently, work is underway on this type of “boosters” of the vaccine. They would prevent infection in a strategic place, that is in the nose and mouth, which the virus attacks in the first place.
In addition, leaving a longer interval between successive doses of the vaccine can also strengthen immunity, as noted by several experts. Therefore, some initially objected to the third dose. However, the omicron and the sharp increase in the number of infected caused them to change their minds.
One vaccine for all coronaviruses
The second route is through the so-called pancoronavirus vaccine. Work on a universal vaccine against coronaviruses is already underway, and the results obtained in the laboratory seem very promising (however, the first small human studies are just taking off).
Recently, scientists at the Walter Reed Army Institute of Research (WRAIR) in the US reported that their trial vaccine appears to offer extensive protection against new and worrying variants of SARS-CoV-2 and against other coronaviruses (such as SARS-CoV-1).
– We are striving to create a pancoronavirus vaccine – one that would provide safe, effective and durable protection against many variants of SARS-CoV-2 and other strains – said Dr. Kayvon Modjarrad, co-creator of the preparation.
The vaccine protects against the hospital
We do not currently have strong scientific evidence that a fourth dose of the vaccine will significantly increase neutralizing antibody levels, and for longer. Perhaps it is worth putting your trust in your immune system and the work that has already been done. After vaccines (after three or two doses), we still have strong cellular protection, i.e. T and B lymphocytes, which take over some of the tasks related to the fight against the virus. They do not protect against omicron infection, but they alleviate the symptoms and course of the disease, thus avoiding hospitalization.
Remember that in the case of the newest or new variants of the virus, the third dose will not prevent infection, but protect against severe disease. This is evidenced by statistics: currently, the absolute majority of patients in intensive care units are patients who have not been vaccinated.
“People who are vaccinated do really well with hospitalization,” said Michel Nussenzweig, an immunologist at Rockefeller University in New York.
To immunize the whole world (and not just our own population)
The coronavirus will continue to spread (and mutate) as long as it does not run out of hosts. And this is one of the arguments in favor of helping countries for which the vaccine is either lacking or unable to afford it.
– If the pandemic slows down in most countries of the world, the risk of new virus mutations emerging is reduced. And this is the argument for helping other nations immunize their populations rather than just strengthening our own, says Dr. Scott Hensley, an immunologist at the University of Pennsylvania.
As experts emphasize, it should be borne in mind that preventing infection requires a different approach than protection against the severe symptoms of the disease. – Or maybe vaccinate first of all children? scientists are now wondering. This strategy works well with pneumococci. Viruses spread quickly between young children and then to adults, so stopping the infection in schools or kindergartens will help protect adults as well.
Source: The New York Times