Updates On Antibody Testing

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Let’s start with the good news: the coronavirus pandemic update in the United States is slowing. Hospitals in NYC and around the country are no longer overwhelmed, and they have adequate PPE and ventilators. The death rate, which most consider a lagging indicator of disease, is trending down across the country. States are finally reporting a good supply of tests, swabs, and reagents, and testing is increasing significantly in most states, including Virginia. State health departments have taken steps to bolster their contact tracing teams to suppress any new outbreaks of disease. In addition, the anti-viral drug Remdesivir has been shown to be effective at reducing the severity of illness in hospitalized patients, and it appears there is significant progress on a vaccine.
Another interesting type of treatment is antibody therapy. Different from treatment with serum from a recovered COVID patient, antibody therapy is the laboratory production of one or more antibodies that can give temporary protection against the virus. While the serum from one recovered patient can treat one sick patient, the monoclonal or polyclonal antibody treatments can be mass-produced. We are still far from clinical trials with this modality, but the race is on between multiple companies to develop this potentially promising treatment.


Having said this, the deaths from COVID-19 have reached 75,000 and will tragically reach 100,000 before August. Life and work restrictions remain in place across the country, social distancing and facemasks will be with us for the foreseeable future, and the economy remains in a very precarious condition. As I predicted in a previous newsletter, the debate about opening the economy has intensified and is following familiar battle lines. Cathy and I hope that politicians and public health experts at the state and national level will find the middle ground that allows the economy to gradually open without risking a large second wave of COVID disease. The bottom line is that each of us, individually, have a responsibility to remain safe and encourage our family and friends to exercise caution regardless of the decisions of our political leaders. You, our patients, have done a marvelous job so far, and we ask that you continue to be cautious. You must resist the temptation to let down your guard.


At Family Healthcare, we have expanded our testing criteria to include most if not all patients with coronavirus symptoms. We hope the supply of tests in our office remains steady, so we can continue to do our part to identify new cases. Each case is reported to the health department, and there has been an effort on their part to contact trace those exposed. We are not fully confident in the effort, so we are supplementing the state’s activity by doing our own contact tracing.
Please note that the Virginia Governor finally has announced plans to expand testing. We have been almost dead last among states in tests per million residents. Virginia, almost certainly, has many more cases than have been identified, and the number of cases will go up substantially in the next few weeks. The CDC has set gated requirements to relax restrictions, which include a
declining number of cases for two weeks, so it is likely that the current expansion of testing in Virginia will affect the time to reach a two-week decline in cases. How an increase in cases due to testing should be viewed when hospitalizations are
declining is a question that needs to be addressed.


Patients are asking us about antibody testing and hoping this test will allow a safe return to normal life or answer whether the illness they had in January/February was COVID. Everyone, including patients, doctors, and politicians, want the following things: a test that guarantees a person is free of coronavirus and not contagious to others, a test that guarantees a person is immune to coronavirus, a treatment that cures the disease if a person gets infected, and a vaccine to prevent a significant outbreak in the future. None of the above exists today but there is substantial progress in all these areas.
Our research informs us that antibody testing is not the panacea most are expecting. So far, limited studies in hard-hit areas (NYC) show antibodies in 15- 25% of patients, but across the US, the expected exposure rate is estimated to be 5% or less. We do not know yet if the antibodies detected will protect patients from catching the disease a second time, although we expect they will, or for how long that protection will last. You may have heard the term “herd immunity,” which is a condition where exposure to disease (natural immunity) or immunization rates reach 50-60%. This is thought to be the level of protection necessary for a population to resist an epidemic, and we are far from that level without a vaccine.
Antibody testing is still not confirmed to be as accurate as normally required of tests used by laboratories. Only a few tests have received an emergency authorization for use by the FDA, and over a hundred are in development. Stories are circulating about the inaccurate results of bad tests, so until we have good evidence of accuracy, we need to be cautious about testing for antibodies. Some of you may be aware that test results can be falsely positive, indicating antibodies are present when in fact the patient was never infected and does not have immunity. False positives happen rarely while testing communities with a large
prevalence of disease but occur as a higher percentage of tests when conducted in areas of low prevalence of disease, undermining the tests reliability and usefulness.
Cathy and I believe there are instances where antibody testing of our patients is indicated, including in highly suspicious cases where the patient tested negative for coronavirus. However, as far as testing for immunity as a passport to return to work, antibody testing is likely to provide misleading information, especially in low-prevalence communities like ours.


At Family Healthcare, we are making plans to reopen the office to patients utilizing a safety protocol that we will soon publish for your review. The video visits have helped enormously, but in-person appointments for physical exams, cancer screening, childhood immunizations, and laboratory tests for serious diseases have been delayed for many patients. Office visits will need to resume to avoid significant medical problems. We believe we will be able to see patients in person safely once the disease curve declines to an acceptable level (mid to late May).
Safety is the primary consideration for you and our staff, and there will be substantial changes in our office procedures to maintain a safe environment for all. If anyone feels uncomfortable with an office visit, we encourage you to contact us to discuss our protocol so that we may reassure you. Please continue to stay physically distanced but socially connected and know that we are always here for you!
For more information please call our office 703-573-6400 or Email: fhfairfax@yahoo.com

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