Survivors of COVID-19 may develop some immunity, but they still need to be vaccinated.That’s why | Lifestyle

Still, there are a surprising number of unanswered questions as to whether millions of COVID-19 survivors have discovered at least one silver-backed immunity.

President Trump has famously declared that he is immune after a bout of the disease. Senator Rand Paul (R-Ky.), Who tested positive for the virus in March, told survivors last month that these people were immune to “throw away their masks, go to restaurants and live again. I should tell you. “

This is not the way immune experts say that you should act after a positive test, but there is new evidence that important markers of immunity remain strong after infection. That does not necessarily mean that the survivor cannot get sick again or spread the virus while asymptomatic.

“We don’t know enough about that scenario,” said John Wellie, an immunologist and director of the Penn Immunology Institute. “We need to be very careful about changing behavior based on previous infections.”

The question of how immunity to this virus works is becoming increasingly important for countries seeking to approve at least two COVID-19 vaccines in an emergency. At a meeting of the Advisory Committee on Immunization and Implementation (ACIP), which makes vaccine recommendations to the US Centers for Disease Control and Prevention last month, members wondered if recently ill people could wait for their injections. It was. First, the missing dose. The group did not make a decision about it.

Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said he believes that COVID-19 survivors should still be vaccinated.

Since these vaccines are brand new, we do not know how long the immunity they provide will last. Jefferson Health’s infectious disease doctor, John Zuro, said it wouldn’t be a big deal if the COVID-19 vaccine lasted for only a year, for example. We are already accustomed to getting a flu shot every year.

One reason scientists feared that natural protection from COVID-19 might be short-lived is that there is a momentary immunity to the milder coronavirus that causes the common cold. Meanwhile, recent studies have shown that the immune system of survivors of SARS, a much more serious type of coronavirus, is ready to fight the virus 17 years later.

In the early days of the coronavirus pandemic, there was evidence that infected people produced large amounts of antibodies, a protein that recognizes the invasion of new coronaviruses and prevents infection. However, the number of these antibodies decreased after a few months.

Since then, more research has focused on antibody-producing B cells and two types of T cells that help kill infected cells or support the immune response. After the virus begins to replicate, T cells begin to function. This means that the virus can be active and transmitted while the immune system is reacting.

A recent study by the Lahora Institute of Immunology, which has not yet been scrutinized by medical journals, found a reason to expect survivors to have persistent immunity.

Examination of all these elements of immunity up to 8 months after infection revealed that in over 90% of people, some of these “memory” cells respond to the coronavirus or some of them. Participating immunologist Daniela Weiskov said. In this study. “This is good news,” she said. The decline in response is slow, indicating that immunity can be long-lasting. But Weiskopf emphasized that “no one knows” what things will look like in a year or 18 months.

But she said the team was only looking at the components of the immune response in laboratory tests. They don’t know if these memory cells actually prevent people from getting sick, but there is good reason to believe so.

There was a great deal of variability in the number of different cells and proteins that individuals had. Researchers do not know how it correlates with the degree of protection.

Weisskopf said the La Jolla study did not analyze differences in the immune system between specific demographic groups. There is a question about how much the most afflicted group of coronaviruses (people over 65 and those with obesity and other chronic health problems) develop immunity. These groups tend to have a weak immune system and may not respond to vaccines or the virus itself. Older people are less likely to benefit from flu shots than young people, but vaccine experts are thrilled to make sure they respond well to the latest shingles vaccine, Shingrix. I will.

The study also did not investigate whether the degree of later immune readiness correlates with how the virus first made people sick.

Obviously, not everyone is protected by either a vaccine or an illness. The first two vaccine candidates made by Pfizer and Moderna protect 94% to 95% of people. That means that some people are still ill.

There are less than 30 known cases of reinfection among COVID-19 survivors worldwide, but more are suspected. Experts said that if most people had not developed immunity, the numbers would probably be much higher.

“I think this shows that we have some immunity after recovering from the primary infection,” Wheely said. “I don’t know how durable it is.”

It is premature to know if innate immunity is superior or different than vaccine-induced immunity.

Zurlo said the recent surge in cases would be a test of innate immunity. He is waiting to see if the reported reinfections will increase significantly.

“After all, the evidence lies in the clinical outcome,” he said. “To be honest, I don’t know if there is a way to hurry it.”

Thomas Fekete, an infectious disease doctor and director of medicine at Temple University’s Luis Katz School of Medicine, is also on the lookout for reinfection. The few he said were “a little relieved. The longer we don’t wake it up, the better I’ll feel.”

He said patients infected with COVID-19 should be wary of reporting mutations in the virus that may affect immunity, perhaps with some protection.

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