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Sitting Out “War”: COVID-19 Antibody Tests

Updated: Apr 24



A Long Island, New York, resident was screened for novel coronavirus antibodies in Hempstead on April 18 (Seth Wenig/Associated Press)

I’m not fighting a war. I’m sitting this one out. I’m staying at home.

U.S. President Donald Trump calls himself a wartime president waging war against an invisible enemy. He is not that.

I am not at war with the novel coronavirus, which is sickening and killing so many around the world.

Coronaviruses are a group of related viruses that cause diseases in mammals and birds. In humans, coronaviruses cause respiratory tract infections that can range from mild to fatal. Mild illnesses include some cases of the common cold, which has other possible causes, while more lethal varieties can cause SARS, MERS and COVID-19, according to Wikipedia. The COVID-19 virus also is called the new, or novel, coronavirus, and SARS-CoV-2. The disease name stands for corona, (CO), virus (VI), disease (D) discovered in 2019 (19).

COVID-19 is highly contagious. But what scares me most is the lack of knowledge about it. Only four months after its first detection, scientists and doctors have not had much time to study it. While educating myself about the disease, I realize that what I’m learning now may change with more research.

Amid the global surge of COVID-19, there are demands for more testing. Diagnostic tests, of which there are many kinds, can detect the presence of the new coronavirus. Antibody tests, of which there also are many, can detect antibodies produced in response to infection. Antibody testing is now at the fore.

The duration and effectiveness of the antibody immune response are still unclear, according to “The Promise and Peril of Antibody Testing for COVID-19” in JAMA (Journal of the American Medicine Association) Network, April 17, 2020.

However, microbiologist Florian Krammer, PhD, of Mount Sinai’s Icahn School of Medicine in New York, told CNN’s journalist Anderson Cooper April 20 that “at this point in time, we make assumptions based on what we know about (the other) human coronaviruses.” Antibodies of the common cold are effective for one to two, maybe three years while those of SARS last two to three years. Krammer emphasized that these timelines are extrapolations that need more studies, which are underway now. He also said that we don’t understand the amount of antibodies needed to protect an individual.

The JAMA publication said: “Antibody tests reveal markers of immune response – the IgM and IgG antibodies -- that for most people show up in blood more than a week after they start to feel sick, when symptoms may already be waning.

“Serologic (blood serum) antibody tests not only can confirm suspected cases after the fact, they can also reveal who was infected and didn’t know it. Up to a quarter of people with SARS-CoV-2 (novel coronavirus) infection may unwittingly spread the virus because they have mild or no symptoms.

“Antibody tests are ramping up quickly, with a growing list of commercial kits and test protocols from academic researchers, including Krammer’s team and a Dutch team coming online in recent days and weeks. Scientists said the tests will be critical in the weeks and months ahead, when they may be used for disease surveillance, therapeutics, return-to-work screenings, and more.

“But the tests must be deployed appropriately, they added, and with an acknowledgment of unanswered questions.”

In Portugal, a number of cities and research organizations are rolling out antibody tests even though national authorities warn that it may be too early to draw conclusions on immunity among the population as a whole, according to Reuters on April 20.

“We can have antibodies after 15 days, but they may not protect us,” said Graça Freitas, head of Portugal’s health directorate, DGS. “When we know more about these tests, they will be very useful.”

In a letter in mid-April, 167 doctors, business and union leaders called on the government to launch widespread antibody tests and contact tracing, according to Reuters.

Some city councils have bought antibody tests from private laboratories for use on their populations or in nursing homes and on frontline staff as a substitute for diagnostic testing for the virus itself.

The Champalimaud Foundation for biomedical research, in Lisbon, is working with the Order of Nurses to test 667 nurses and auxiliary staff the week of April 19 in Lisbon and Porto, using German tests, a foundation spokesperson told Reuters.

A consortium of research institutes at the University of Lisbon, Nova University of Lisbon and the Gulbenkian Science Institute hopes to mass-produce inexpensive tests by the end of the week of April 19, said Gulbenkian director Monica Bettencourt-Dias.

Also, in Portugal, the Ricardo Jorge National Institute of Health, a public health organization of the Ministry of Health, aims to launch a pilot antibody testing project with a sample of 1,700 people in the coming weeks, said Reuters. It also is evaluating a method of curing seriously ill patients through infusing blood plasma from people who have recovered from COVID-19.

Germany and Italy will conduct large-scale antibody testing. Germany plans to issue “immunity certificates” to transition its citizens out of lockdown, said the Journal of the American Medical Association article on April 17. The National Health Service in Britain is discussing plans for nationwide antibody screening which would begin once a rapid at-home finger-prick test under consideration is assessed for accuracy. The Guardian reported on April 11 that Britain had bought 3.5 million unusable tests which proved to give wildly inaccurate results. In the United States, the White House has not announced similar antibody testing plans.

As with diagnostic COVID-19 tests, there are different kinds of antibody tests.

Both the Mount Sinai and United Biomedical tests are enzyme-linked immune sorbent assays, or analysis, (ELISAs), a common laboratory platform that uses a solid-phase enzyme immunoassay to detect the presence of an ion or molecule, commonly a protein, in a liquid sample using antibodies directed against the protein to be measured.

“However, a substantial number of the new commercial COVID-19 antibody tests aren’t ELISA-based. They’re lateral flow assays (simple devices, such as the home pregnancy test, intended to detect the presence of a target substance in a liquid sample without the need for specialized and costly equipment), which provide a simple positive or negative result, with no quantitative information. These kits are cheap and easy to use and, depending on how they’re employed, may be helpful for disease surveillance,” said Elitza Theel, PhD, director of the Mayo Clinic Infectious Diseases Serology Laboratory in Rochester, Minnesota.

Diazyme Laboratories in Poway, California has developed chemiluminescence immunoassays, which are nearer in concept to ELISAs than lateral flow assays. The tests generate a light signal proportional to COVID-19 IgM antibodies, according to the JAMA publication.

The Food and Drug Administration has received requests for Emergency Use Authorization from 120 antibody-test developers. As of mid-April, it has granted formal approval to only four: the Mount Sinai Laboratory, Cellex Inc in Research Triangle Park, North Carolina, Chembio Diagnostic Systems and Ortho Clinical Diagnostics, according to The New York Times.

Also, in April, the FDA allowed about 90 companies to sell COVID-19 antibody tests without this emergency authorization, albeit with some stipulations, said the JAMA publication. Manufacturers, for example, must state they have clinically validated their tests using specimens from patients with confirmed infections. Also, the test reports must note that the FDA has not reviewed the assays and that they should not be used as the sole basis to diagnose or exclude the new coronavirus infection or to inform patients of infection status.

Several companies are marketing lateral-flow tests as rapid, point-of-care tests to identify active COVID-19. The FDA will take action against them, said Theel of the Mayo Clinic in JAMA Network. “We really do not know how well these assays work at this point.”

There are so many unanswered questions about COVID-19.

The one thing we do know is that quarantining ourselves will reduce exposure to the new coronavirus and transmission of it. Staying at home is the only certain strategy to prevent the virus from entering our lives and farther infiltrating our communities.

In my six weeks of retreat, breakfast is my constant as it was before the three 15-day States of Emergency began in Portugal. I begin my days with the smell of coffee and lemons, classical music on the radio and a few Jumble word puzzles. After that, anything could happen, anything but fighting battles under the marshaling of a narcissistic president.

Metaphors of war don’t comfort me in this global pandemic. In fact, they frighten me. They seem like a desperate grasp at leadership by a weak man.

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© 2017-2020 by Cynthia Adina Kirkwood