The question was: “Do you have covid?” Now it’s: “How many times have you got it?” We’ve both had covid (re) infections in recent months. Most of us have a laid back attitude when it comes to painting a picture about a loved one. In the week ending June 24, 1 in 30 people (approximately 2.3 million people) in the UK were infected with covidosis, 32% more than the previous week. (Also read: Mild Covid Side Effects: To See General Long Covid Symptoms)
It largely reflects a mutable virus. The UK’s Health Safety Agency estimates that too many transmissible subarachnoids of Omicron make up more than half of all BA.4 / 5 new infections. Centers for Disease Control in the United States came to a similar conclusion.
While people with Kovid are still hospitalized, and there are still Kovid deaths (especially among the very weak or non-vaccinated), most people who are vaccinated recover quickly, although the disease can still be bad for many. “In terms of its kind of lethality, the picture is much, much, much closer now than it was for the seasonal flu. [coronavirus] Appeared for the first time, “Jonathan Van-Tam, deputy chief medical officer for the East of England, recently told the BBC.
This leaves the question of how to manage the virus in the coming winter. On the one hand, countries with high levels of vaccination should have higher flexibility and therefore lower restrictions. On the other hand, the virus’s ability to mutate means that high infection levels pose a risk. We discuss what lies ahead for booster shots and other strategies to include epidemics.
Theres Raphael: Pfizer Inc. And Moderna Inc. Both have announced that their candidate vaccines targeting Omicron will provide more powerful and potentially more durable immune responses. The FDA’s advisory panel on Tuesday recommended that the updated Covid-19 booster shots contain omicron components. Do you think it is right to go ahead with Omicron-specific booster?
Sam Fazeli: There was some uncertainty among members of the FDA panel as to whether the Omicron shots could defeat the current vaccine, but the majority believed that vaccines containing the Omicron sequence had a better chance of being beneficial against Omicron while providing immunity against other variants. However, when you look at the data presented by the companies, they both failed to show the statistical superiority of their new vaccines against BA.1 compared to the currently available shots.
TR: So what gives the panel the confidence that they will be the best?
SF: The shots still showed improved antibody responses in BA.1, the original Omicron version. But the panel said they want a BA.4 / 5 omicron shot, and I think regulators will ask companies to update their vaccines again. Data from shots based on Omicron BA.1 induced three times less neutralization against BA.4 and BA.5 than BA.1. My math suggests being 50% effective against BA.4 and BA.5 infections after three to four months.
Pfizer has already begun work on vaccines to counter BA.4 and BA.5, and they showed some promising data at the meeting looking neutral in mice. If those findings reach humans, it would make a better vaccine than a vaccine based on BA.1.
TR: This is good, because most of us who are re-infected seem to be getting later subvariets. It’s not too hot here, but thinking ahead, should we do something different this winter? Especially with the flu, is it possibly more prevalent than the previous two years? Or will the level of natural immunity work as booster shots?
SF: Neither vaccinations nor previous infections are going to prevent re-infection. I was fully vaccinated and tested positive two weeks before the Delta infection last October. Vaccination can delay it for a few months, but infections will eventually occur, although Moderna is right that a bivalent vaccine (treatment of both Omicron and previous versions) can induce long-lived antibodies.
In terms of infection, the concept of herd immunity is really dead. What we need to do is ensure that the weakest segments of the population are protected against serious diseases, as noted by the FDA panel several times. Whether it’s people over 65 or 60 or over 50, we’ll see what the FDA says.
TR: We were told that mRNA technology could be easily adapted to fit emerging virus strands so it’s no surprise that we don’t even have a booster shot for BA.1 on the market. Why not
SF: Well, don’t forget that this is the first time we are updating vaccines and the virus is changing very fast. Nevertheless, Pfizer mentioned in the meeting that it could produce BA.4 / 5 shots by September and higher modes by October or November. This suggests that the FDA does not require a large human test with a few months of safety data. Both companies still insist on production within 90 to 100 days.
TR: There are two things that most vaccinated people worry about when they think of new covid versions. One is the risk of serious disease and the other is long covid. Have those risks changed in light of BA.4 / 5?
SF: Data from South Africa and Portugal do not suggest a major change in severity with BA.4 / 5 compared to BA.1. But don’t forget that this is the background of many people infected with BA.1 in the first omicron wave, so it’s not easy to compare.
It is noteworthy that recent studies show a much higher severity after re-infection, which included the Omicron variant. The problem is that this study was conducted on patient data from the U.S. Department of Veterans Affairs Electronic Health Records, in which most subjects are over 60 years of age and have comorbidities that increase the risk of serious disease. It is also noteworthy that most of the vaccines included in the analysis were not vaccinated.
But its biggest flaw is what we call “test bias”, which arises when some members of the target population are less likely to be included than others. For example, if most people do not bother to get tested officially if they have mild symptoms due to a re-infection, the data will deteriorate into a more serious disease that is highly evaluated.
In the case of long covid, recent studies have shown that Omicron appears to cause shorter covid cases than previous versions. Note, this was in the UK, where many people have been triple-vaccinated.
TR: Most of us face re-infection this winter. Does this make it possible for us to see another significant mutation with greater potential for immune avoidance? Will the updated vaccines be able to protect us from new variants?
SF: The problem is that we don’t know what the next version will look like. Everyone thought that any new variant would be based on the Delta variant – instead it came with a host of mutations from the left zone that Thoreau had hoped for. Using a bivalent vaccine may already be the first step towards a polyvalent shot. However, we must not forget that most people are either vaccinated or infected, so these booster shots are on top of pre-existing immunity. This leads to immune imprinting, where the body is forced to make similar antibodies.
In terms of new mutations, it is not background immunity that has so far led to large mutant jumps such as omicron but long-term infections in immunocompromised individuals.
If there are major changes to the Omicron again or a completely new variant appears, we may need to develop another variant of the vaccine. However, if immune imprinting is not a problem, vaccination with each frequent infection or updated vaccine broadens the immune response and reduces the risk of serious disease. Unfortunately, as antibody levels drop within a few months of each infection or vaccination, there is a risk of re-infection and mild disease recurrence.
Theresa Raphael is a columnist covering health care and British politics for Bloomberg Opinion. Prior to that, she was the editor of the Wall Street Journal Europe.
This story has been published from the wire agency feed without modifying the text. Only the headline has been changed.