Bold expectations for virus antibody tests are still incomplete


WASHINGTON (AP) – At the height of the coronovirus lockdown, President Donald Trump and his top health advisers conducted a new test, which would help Americans reclaim their lives – one that would tell them if they already had the virus. Was and was saved from being received. Again.

His arrival would help “get Americans back to work,” which could show “amazing, beautiful immunity,” Trump said, repeating a point in the daily briefing last April.

Months later, the US is aware of the tests, but bold predictions about their usefulness are yet to materialize.

Dr. of New York City’s Public Health Laboratory. “There was definitely a lot of wishful thinking that there was going to be a magical ordeal that was going to save us all, but we’re not there yet,” said Alison Rakman.

The tests examine the blood for antibodies that the body makes to fight an infection. Scientists are still working to find out how antibodies to coronovirus can protect someone from another infection, or how long there may be protection. Some early studies suggested intensifying any immunity; Research published last week was more promising, suggesting that antibodies last for at least four months after diagnosis and do not fade quickly.

For now, the Centers for Disease Control and Prevention and the American Medical Association explicitly warn that antibody tests should not be used to make decisions about whether the office or students return to school, although some laboratories still use those. Promotes them for. The CDC recommends everyone – even those who were ill and cured – take precautions to prevent the virus from spreading and spreading.

Experts say it was probably unrealistic to expect answers to key immune questions in the outbreak. Mark Jenkins of the University of Minnesota said those questions have traditionally been answered through long-term animal or human studies.

The National Institutes of Health and Universities are conducting some of this work, but most of it is a seat to the rapid development of vaccines in the midst of an epidemic.

“Everyone is impatient and I can see why,” Jenkins said. “But there is no easy path to this knowledge about immunity”.

Antibody tests are different from standard nasal swab tests that diagnose active infection. Instead, they use a blood sample or finger prick to look for signs of a chronic infection, whether the person was ill or had no symptoms. Depending on other viruses, experts expect those with coronovirus antibodies to be at least partially immune for several months, if not longer.

Dr. Anthony Fauci and other members of the White House task force said it was soon a reasonable assumption that “if you have antibodies, you are safe” but said there was no evidence.

To get that evidence, scientists first experiment in animals. Human trials come next and may take even longer. Researchers track those who have had infections and develop antibodies to see if they are reinforced. Their antibodies are measured to measure the level required for immunity.

Jenkins and others stated that it is entirely possible that an effective vaccine will arrive before the completion of a coronovirus antibody study, which will help answer some key questions. Vaccines promote the production of antibodies, and many coronavirus virus vaccines are now being tested worldwide.

Meanwhile, experts say antibody tests are useful for two things: large studies in the general population to see how widely the coronovirus has spread, and are examining people who have their antibody-rich blood May be able to donate plasma, which is used. Experimental treatment for COVID-19.

But according to Nielsen, those uses did not receive the attention of White House briefings last year, which attracted between 8 million and 10 million cable TV viewers. A spokesman for the White House Coronovirus Task Force did not respond to a request for comment.

Anticipating the huge demand, the Food and Drug Administration chose a “flood-the-zone” strategy, allowing more than 170 trials to be launched with greater oversight.

At the same time, Trump highlighted the “spectacular progress” of his administration, bringing antibody testing to market, with some officials expressing concern. Reports from European governments forced millions to abandon faulty tests.

Admiral Brett Girir, the administration’s “test czar”, said, “We’re going to take great care to make sure when we tell you that you’re potentially immune to the disease … the test actually said that,”.

The FDA pulled back on its loose policy for antibody tests in May, forcing companies to start presenting data on accuracy. The FDA has thus authorized about 40, while dozens more are awaiting review.

Despite precautions from regulators, some testing companies continue to advertise tests for workers and others. Larger labs, including LabCorp and Quest, offer employers tests, along with other services such as temperature checks.

“We are aware of the CDC’s guidance,” Quest spokesman Kimberly Gorod said in a statement. This is why we recommend that employers use antibody testing as part of a holistic approach to return their employees to the office.

LabCorp said in a statement: “As knowledge increases, there may be benefit in having access to this information.”

At testing sites in New York City in April, doctors with Somos – a medical nonprofit service to low-income communities – told people who tested positive for antibodies that they could safely return to work , Although he admitted that “nothing is 100%.” In a recent interview, the group’s founder Drs. Ramon Tallaz defended the trial. He said that the workers would be expected to return anyway. He said that antibody testing only provides “an extra layer of protection”.

The CDC and state public health agencies continue to use antibody testing to track the spread of the virus in the US. In most areas studied so far, less than 5% of the population has antibodies. This is far below the level that most experts think would be necessary for herd immunity against coronaviruses, underscoring the need for a vaccine.

For now, Jenkins does not recommend spending money to test for antibodies unless doctors recommend it.

“Even the research community can’t really tell you what the results mean,” Jenkins said.

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Follow Matthew Peron on Twitter: @AP_FDAwriter

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AP videojournalist Marshall Ritzel in New York contributed to this report

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The Associated Press Department of Health and Sciences has support from the Science Education Department of the Howard Hughes Medical Institute. AP is solely responsible for all content.