Scientists disagree whether infection and vaccination give equal Covid protection

Dr. Aaron Kheriaty, a psychiatry professor at the University of California, Irvine, said he didn’t need to be vaccinated against Covid-19 because he contracted the disease in July 2020.

In August, he sued the university system’s vaccination mandate, saying that “natural” immunity had given him and millions of other people better protection than any vaccine could.

A judge dismissed Kheriaty’s motion for an injunction against the university because of her mandate, which went into effect on September 3. While Kheriaty plans to pursue the case further, legal experts doubt that his and similar lawsuits, filed across the country, will ultimately be successful.

However, there is growing evidence that contracting SARS-CoV-2, the virus that causes Covid-19, is generally as effective as vaccination at stimulating your immune system to prevent the disease. However, federal officials were reluctant to recognize equivalence, citing the wide differences in Covid patients’ immune responses to infection.

As with many disputes during the Covid pandemic, the uncertain value of previous infection has created legal challenges. Marketing offers and political tribune, even when scientists work quietly in the background to clarify the facts.

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For decades, doctors have used blood tests to determine whether people are protected from infectious diseases. Pregnant women are tested for antibodies to rubella to make sure their fetuses don’t get infected with the rubella virus, which causes devastating birth defects. Hospital workers are screened for antibodies to measles and chickenpox to prevent the spread of these diseases. But immunity to Covid seems more difficult to detect than immunity to these diseases.

We don’t yet know exactly what the presence of antibodies tells us about immunity.

The Food and Drug Administration has approved the use of Covid antibody tests, which can cost around $ 70, to detect previous infections. Some tests can differentiate whether the antibodies are from infections or vaccines. But neither the FDA nor the Centers for Disease Control and Prevention recommend using the tests to determine if you are actually immune to Covid. The tests are essentially useless for this, as there is no consensus on the amount or type of antibodies that would signal protection against the disease.

“We don’t yet know exactly what the presence of antibodies tells us about immunity,” said Kelly Wroblewski, director of infectious diseases at the Association of Public Health Laboratories.

Likewise, experts disagree on how much protection an infection offers.

How does natural immunity compare to vaccination?

In the absence of certainty, and with vaccination regulations being imposed across the country, lawsuits seek to advance the issue. People who claim vaccination regulations violate their civil liberties argue that the immunity acquired through infection protects them. In Los Angeles, six police officers have sued the city, claiming they have natural immunity. In August, law professor Todd Zywicki alleged that George Mason University’s vaccination mandate violated his constitutional rights because he had natural immunity. He cited a series of antibody tests and an immunologist’s medical opinion that vaccination was “medically unnecessary”. Zywicki dropped the lawsuit after the university granted him a medical exemption that allegedly had nothing to do with the lawsuit.

Republican lawmakers have joined the crusade. the GOP doctors caucus, made up of Republican doctors in Congress, has urged people suspicious of vaccinations to get antibody tests instead, in contravention of the CDC and FDA recommendations. In Kentucky the state senate has decided a resolution granting the same immunity status to those who show evidence of vaccination or positive antibody tests.

Hospitals were among the first to mandate vaccinations for their frontline staff, as there was a risk they could pass the disease on to vulnerable patients. Only a few offered exceptions to those previously infected. But there are exceptions.

Two Pennsylvania hospital systems allow clinical workers to postpone vaccination for a year after testing positive for Covid. Another in Michigan allows employees to decline the vaccination if they have had infections and positive antibody tests in the past three months. In these cases, the systems indicated that they were careful to avoid staff shortages that could result from the departure of nurses who refused to be vaccinated.

Everyone is just waiting for Fauci to say: “A previous infection offers protection”.

For Cheriaty, the question is simple. “The research into natural immunity is now pretty much final,” he told KHN. “It’s better than immunity given by vaccines.” But such categorical statements are clearly not shared by most in the scientific community.

Dr. Arthur Reingold, epidemiologist at the University of California, Berkeley, and Shane Crotty, virologist at the prestigious La Jolla Institute for Immunology in San Diego, issued expert reports In the Kheriaty lawsuit, the level of immunity from re-infection, particularly against newer variants of Covid, is unknown. You noticed that Vaccination gives a huge boost to immunity to people who have already been sick.

Yet not all rush Recognizing past infections are vaccination critics or torchbearers of the anti-vaccine movement.

Dr. Jeffrey Klausner, clinical professor of population and public health at the University of Southern California, co-authored an analysis released last week this showed that infection was generally protective for 10 months or more. “From a public health perspective, there is no point in denying jobs and access and travel to people who have recovered from infection,” he said.

In his testimony against Kheriaty’s case for “natural” immunity, Crotty cited studies on the massive Covid outbreak that swept Manaus, Brazil earlier this year that involved the gamma variant of the virus. One of the studies estimated, based on donor blood tests, that three-quarters of the city’s population were infected before Gamma arrived. This suggested that previous infection may not protect against new variants. But Klausner and other suspect that the rate of previous infections presented in the study was a gross overestimation.

A big study in August from Israel, which showed better protection against infection than before vaccination, could help turn the tide towards acceptance of an earlier infection, Klausner said. “Everyone is just waiting for Fauci to say, ‘A previous infection offers protection,'” he said.

When Dr. Anthony Fauci, the foremost federal infectious disease expert, asked in a CNN interview Last month, he wondered whether infected people were protected as well as vaccinated people. “There could be an argument,” he said. Fauci did not immediately respond to a request from KHN for further comments.

CDC spokeswoman Kristen Nordlund said in an email that “current evidence” shows large differences in antibody responses after Covid infection. “We hope to have some additional information on protecting vaccine immunity versus natural immunity in the coming weeks,” she said.

A “monumental effort” is underway to determine which antibody level is protective, said Dr. Robert Seder, the head of the Cell Immunology Department at the National Institute for Allergies and Infectious Diseases. Youngest Have studies taken a stab at a number.

Dr. George Siber, a vaccine industry advisor and co-author of one of the papers, said antibody testing will never give a yes-or-no answer to protection against Covid. “But there are people who don’t get vaccinated,” he said. “Trying to predict who is at low risk is a worthwhile endeavor.”

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