Vaccine Will Be Effective Against New Strain Of COVID-19, Doctor Says | TODAY
Hildegund Ertl:; We cannot rule out the possibility that even people vaccinated with Pfizer or Moderna vaccines can contract the coronavirus and infect others with it
Can a person vaccinated against a coronavirus become infected and infect others? Will existing vaccines against new strains of coronavirus help? When can we get back to normal? Hildegund Ertl, professor at the Hildegund Ertl, The Wistar’s Vaccine Immunotherapy Center, answers these and other questions from the Voice of America correspondent..
Margot Gontard: Can a person vaccinated with Pfizer or Moderna vaccines get the coronavirus and infect others?
Hildegund Ertl: We learned from clinical trials that the vaccine helps to ease the course of the disease and avoid complications. This means that vaccinated people do not die when they contract the coronavirus. At the same time, they may not have symptoms of coronavirus. But the absence of symptoms does not mean the absence of the virus: vaccinated people can become infected, get an upper respiratory tract infection. The disease is likely to be milder and therefore less likely to infect others. But this issue has not been sufficiently studied yet..
Much depends on what the clinical research is focused on. Astra Zeneca tested vaccinated patients for the COVID-19 virus and found that 70% of people vaccinated with their vaccine developed immunity against the virus, which means they could no longer infect it or infect others. At the same time, Pfizer and Moderna focused their research on the symptoms of the coronavirus. Therefore, the results of their studies do not answer the question: can vaccinated people become asymptomatic, infect others, and how long can this take place? We just do not have this information yet..
M.G .: Relatively recently, two new strains of coronavirus have been discovered. How they differ from the ubiquitous COVID-19 strain?
H.E .: The strain found in the UK has indeed mutated, but only slightly. Pfizer has analyzed the antibodies of those people who were vaccinated against the main strain of coronavirus to test the effectiveness of these antibodies against the new strain. They turned out to be similar in many ways. So there is a good chance that these antibodies will protect against this strain as well. Accordingly, we believe that existing – and licensed – vaccines will be as effective against the UK strain as against the old COVID-19 strain..
As for the strain found in South Africa, it has mutated much more. And the more mutations a virus has, the more difficult it is to create an effective vaccine. I have not heard of anyone conducting a study on whether the South African strain is neutralized by antibodies arising from an immune response to pre-existing vaccines. So, at the moment, we do not have an answer to this question..
We are currently in the process of working on a vaccine effective against strains originating in the UK and South Africa. I’m sure Pfizer and other companies are working to make sure we are protected from these mutations..
M.G .: How often will it be necessary to re-vaccinate if existing vaccines are used, and how long will the immunity arising from their action last?
H.E .: This will depend on the vaccine. To be honest, we don’t know that at the moment. Preclinical studies have shown that the immunity acquired through adenovirus vaccines lasts long enough. We have been conducting clinical trials of adenovirus rabies vaccine in monkeys for a year and a half. The antibody level remained stable throughout the entire period. When we exposed the monkeys to the rabies virus, they all survived. Based on the results of one and a half years, it can be concluded that the amount of antibodies in the blood of monkeys decreased slightly. Of course, monkeys are not people, but they are the closest species to humans, from the point of view of genetics. So my guess is that adenovirus vaccines elicit a fairly robust immune response. My guess is that the immunity created by the AstraZeneca vaccine will last for years, if not decades..
It is difficult to guess how long the reaction is caused by RNA vaccines (such as Pfizer and Moderna – Voice of America). My guess is that RNA vaccines may have a shorter exposure to humans, but we don’t know for sure. We only started developing vaccines in February, and only in June we conduct clinical trials, so at the moment we can only say that the vaccine provides guaranteed immunity for 4-5 months. We do not yet have data on longer periods. I am confident that Pfizer and Moderna continue to monitor the effectiveness of their vaccines. Only over time will we find out how much the immunity acquired thanks to them is enough, and how often we will need to re-vaccinate.
M.G .: This is because RNA vaccines are being used for the first time.?
H.E .: In fact, there has already been one clinical trial of an RNA vaccine against rabies in the past. The immunity caused by it did not last very long: after a year it was gone. Of course, this was quite a long time ago, and I am sure that the technology for creating RNA vaccines has been improved since that time. So I am not suggesting that any RNA vaccine will provide short-term immunity. All I am saying is that we need to monitor and repeat vaccinations if necessary..
M.G .: Every day there are more and more vaccinated people. Who is watching over their condition, and how exactly does this happen? How and under what conditions can a decision be made on the need for re-vaccination?
H.E .: Once the vaccine is on the market, the company has little control over the process. I am confident that the US Centers for Disease Control and Prevention will continue to collect data on how many people get sick, how old they are, what origin, where they come from, and how many of them have been vaccinated. I’m sure that now, when people come to the hospital with coronavirus, the first thing doctors ask is: have they been vaccinated against COVID-19, and they report this to the Centers for Disease Control and Prevention..
True, it will be rather a belated signal. Participants in the final phase of vaccine clinical trials will be observed more closely. It is much easier: after all, the company conducting them can control this process. Test participants are usually followed for at least a year, if not longer. Therefore, we already know that those who received the vaccine are 92% protected from the disease: these are the test results published in December. They continue to be watched. So if, for example, in April, companies see the vaccine efficacy decrease, say, to 70%, I’m sure they will notify us..
M.G .: How common are allergic reactions to vaccines??
H.E .: Allergic reactions to vaccines are common. This can usually be predicted in this way: for example, if a person is allergic to eggs, he should not get the flu vaccine. Again, there is a difference between skin redness and an anaphylactic reaction. About one in 100,000 Americans vaccinated by Pfizer has an anaphylactic reaction. This is a fairly high score, as the usual average is about one person in a million..
M.G .: What Can Cause Allergies If You Get The Pfizer Vaccine?
H.E .: One of the oils that has been added to the RNA vaccine to improve efficacy, called polyethylene glycol, is likely the cause of the allergy. By the way, I myself am allergic to peanuts. However, nuts and polyethylene glycol are like heaven and earth. Unless you are allergic to components of the vaccine, which can be found on the Internet, your personal allergies will not affect the effect of this vaccine on you. Again, while allergies are not great news, they are very easy to deal with. If I had a choice between an anaphylactic reaction to a vaccine in a hospital setting, where a doctor or nurse can immediately inject me with epinephrine, and the chance of contracting COVID-19, I would confidently ask for the vaccine..
On the other hand, if you have an anaphylactic reaction after the first dose of the shot, you probably won’t want to ask for a second dose. In this case, you can ask for another vaccine..
M.G .: Are there any other illnesses or medical conditions that you consider to be a contraindication to being vaccinated with existing vaccines??
H.E .: At the moment, we do not have enough information about this. In the news, there was a recent case where a healthy doctor in Florida was vaccinated with the Pfizer vaccine and later developed a complication and passed away. According to his wife, this was due to the vaccination. This may have been the case, but one case is not enough to state this with certainty. At this point, I believe that negative side effects from approved coronavirus vaccines are extremely rare and that people should get vaccinated..
M.G .: When can we get back to normal?
H.E .: I think that somewhere in the late summer or autumn of this year. We will definitely need to continue wearing masks for a while even after more people are vaccinated: after all, even if a person is vaccinated, they can still pick up the virus and infect others. I think people will need to wear masks until we are convinced that the rate of increase in incidence has significantly decreased..
Let’s say I get grafted and want to fly to Europe. I will be able to do this, but I will be wearing a mask on board the plane and will wear it on the trip and when I return to the United States. The reason is very simple: even though I know I won’t die or get sick if I get infected, I risk the lives of other people because I can still infect them if I catch the virus..
So I think that by the end of summer or by the middle of autumn in the United States, most people will be vaccinated, and the incidence rate will decrease significantly. For example, instead of 200 thousand new cases of infection per day, we will have 10 thousand, and then two thousand. Then we can relax the rules for maintaining social distance. True, we will probably still wear masks. I think this will last for a while. This is if the virus does not mutate enough that existing vaccines will no longer work against it. In this case, obviously, it will all take longer..