Thank you for listening to our last townhall discussion about Covid issues, and the many kind remarks. I will divide the frequently asked questions into four broad categories: Covid testing limitations, vaccine boosters after acquired immunity, questions about therapies and laboratory confirmation of cellular immunity (T-cell testing).
1. What are the limitations of testing for acute Covid infections?
Different Covid tests have strengths and weaknesses. The rapid antigen tests are most sensitive between days 2 and 5 of illness. If the rapid antigen test is positive, one with Covid symptoms has evidence of the SARS-CoV-2 spike protein and this evidence confirms the infection. The rapid antigen test is more likely than the PCR test to give a “false negative” result. It is not as sensitive as the PCR test and was not designed to test asymptomatic people. The Omicron variant is very contagious. If someone in the same household tested positive and another resident is symptomatic with Covid-like symptoms, they can assume that they are infected with the Omicron variant.
The PCR tests amplifies viral genetic material, but it does not differentiate between active and inactive viral genomic particles. A PCR test does not always differentiate between a previous infection and an active infectious state. The presence of Covid symptoms and the number of days after an illness begins are better predictors of one’s risk of transmitting the virus to others.
2. Should I get a Covid booster shot after natural infection?
Physician opinions differ about how to answer this question. The CDC recommendation is to get a booster after natural infection. They previously recommended a 90-day delay after infection, but now recommend a booster after full recovery. The booster can be given if there has been an appropriate time lapse after the previous Covid inoculation and monoclonal antibodies were not used as a treatment for the infection. If monoclonal therapy was used for an infection, a Covid booster shot should be delayed for at least 90 days.
During my presentation, I opined that every individual should be able to exercise choice based upon their own health considerations, personal risk factors and existing immunity. They should also have the right to discuss questions with their physician to make an informed decision. I do not agree with vaccine mandates or passports for SARS-CoV-2. My hope is that the Omicron variant will serve as a live attenuated vaccine, and our communities can move on from these authoritarian directives.
3. There were multiple questions about therapeutic interventions for acute Covid infections.
As a physician practicing for over 27 years in the outpatient and inpatient settings, I have always appreciated well researched guidelines to help me improve therapeutic choices for my patients. However, there was always an understanding that guidelines do not substitute for a physician’s judgement or the informed consent process. These basic concepts were seemingly deemed no longer relevant by many during this pandemic.
During pandemics, traditional medical practice is not suspended, and clinical decision making is not delegated to non-treating physicians because the leadership of some medical institutions assume that privilege. My immediate responsibility is to my patients. These institutions will never be able to adjust treatment based upon real time empiric evidence and rapidly changing clinical data and research. Physicians on the front lines who have treated Covid patients began to understand the stages and patterns of disease. Many of us read research concurrently to help the patients in front of us. Our skills in treating this disease improved significantly over time.
It is true that treating early and empirically has brought unwanted regulatory attention. We have been very careful not to “promote” any specific treatment modality. We believe that early treatment efforts attenuated the hospitalization rates in our community during the Delta surge. I provided data to support this statement during the presentation. A future townhall discussion may include the complex subject of Covid therapeutics, but it was not the focus of this presentation.
4. How do you test for T-cells?
We have used the T-detect test supplied by Adaptive biotechnologies. This test received emergency use authorization in 2021. It has been used in clinical research as well. It has a 99.8% specificity for SARS-CoV-2 and a sensitivity of 95% at 6 months and 90% at 10 months after an infection. Insurance does not pay for the test. Most people do not need the test. If one tested positive with a rapid antigen test while having symptoms, immunocompetent individuals will develop T-cell immunity or immunity with a memory. Some commercial labs (Quest or LabCorp) may draw the blood for the test and send the sample to Seattle, Washington. Most labs are charging about $250 for the T-Detect test. Please understand, this is not an advertisement since most people do not need the test. For those who do want to confirm that they had Covid in the past, Evergreen’s Occuhealth still has some tests available, and the charge is $200. The test result returns in 7-10 days as a positive or negative result for evidence of T-cell immunity against COVID-19. The test is not authorized for use under the age of 18.
Lastly, since my presentation that included a discussion about the protective effect of natural or recovered immunity, the CDC published this document on 1/19/2022. It provides evidence that recovered immunity protected people from hospitalization in New York and California during the Delta surge.
The diagram below from the CDC study shows that natural immunity protected against hospitalizations as well or better than vaccination during the Delta surge.