What is COVID-19 and SARS-CoV-2?
SARS-CoV-2, a Betacoronavirus, is a direct relative of the highly deadly SARS-CoV-1 virus and is the causative virus for COVID-19, a multifaceted disease that can display “flu-like” symptoms and lead to severe respiratory distress and organ failure. COVID-19 currently displays an approximately 2.2% mortality rate (~2 out of 100 exposures result in death) in the United States, much improved over the >5.0% mortality rate experienced in the United States early in the pandemic as research and treatments have evolved and improved over time. Though symptoms can be similar, the mortality rate of the seasonal flu in the United States is ~0.1 – 0.2%, in part due to differing cellular effects as well as decades of research and evolving treatments for an established virus as compared to the novel SARS-CoV-2 virus.
How does SARS-CoV-2 affect me?
SARS-CoV-2 has been shown to be highly transmissible, being easily passed from person to person, with recent research suggesting airborne transmission where person-to-person contact is not required to “catch” the virus. Controlling this virus is made all the more difficult by the existence of asymptomatic “carriers” who do not have those elements or underlying conditions that can lead to severe disease. However, these individuals can easily transmit the virus to those who are at highest risk. As with most respiratory viral infections, individuals at highest risk of severe illness from SARS-CoV-2 include those with underlying medical conditions, including Type 2 diabetes, COPD, heart conditions, obesity, pregnancy, sickle cell anemia, current/former smokers, and those in an immunocompromised state such as the elderly, cancer patients, and those that suffer from autoimmune disorders.
DevLab bio offers a variety of testing that can help you understand more about Covid-19 and your health. Patients can determine exposure and understand progression in their immune response, allowing them to protect themselves and others. All testing offered by DevLab bio is FDA EUA approved, with the exception of IgA antibody testing (currently pending FDA EUA approval).
What kind of testing does DevLab bio offer and why is it important?
SARS-CoV-2 RT-PCR – THE Gold Standard of SARS-CoV-2 testing. Using nasal/nasopharyngeal swabs collected by trained professionals, the genetic material (RNA) of the SARS-CoV-2 virus can be detected early in infection within 1 week of initial exposure in asymptomatic or symptomatic individuals. Early detection is the key, allowing the individual to take appropriate preventative measures to prevent spread of the virus to others around them and in their community.
Antibody Testing – Antibodies are the human bodies natural response to infection and can be an indicator of recent infection, recovery, and potentially short-term and/or long-term immunity. Using blood collected by trained phlebotomists, Immunoglobulin M (IgM), Immunoglobulin A (IgA), and Immunoglobulin G (IgG) can be detected in serum following exposure to SARS-CoV-2.
IgM Antibodies – IgM antibodies are the body’s initial immune response to infection. IgM antibodies provide the initial short-term immune response and first appear early in infection, sometimes within the first week following exposure. The presence of IgM antibodies can be a key determinant in whether an individual has been recently exposed to SARS-CoV-2. If an individual is positive for SARS-CoV-2 RNA, they will most likely be positive for IgM antibodies against the virus. IgM antibodies will seroconvert to IgG antibodies.
IgA Antibodies – IgA antibodies appear within the first two weeks of SARS-CoV-2 infection and although detectable in human serum, they are at their highest concentrations in saliva and mucous due to their production by cells located in mucosal surfaces. Research is ongoing as to the role of IgA antibodies in the immune response to IgA but are believed to be a potential source of protection due to localization in saliva and mucous, the first location SARS-CoV-2 and other respiratory viruses typically encounter in an infection. IgA antibodies will seroconvert to IgG antibodies.
IgG Antibodies – IgG antibodies are the final class of antibodies to arise in the body, near 2 weeks post-exposure, and are associated with the bodies long-term sustained immune response. IgG antibodies can be long lasting well into convalescence/recovery and even after full recovery. The length of time IgG antibodies against SARS-CoV-2 last in the human body and immunity they confer may vary by individual and is an area of a depth of current research.
COVID-19 Protective Antibody Test (DevNab)
Protective (neutralizing antibodies) are a specific “class” of IgM/IgA/IgG antibody isotypes able to disrupt SARS-CoV-2 viral entry into host cells by interacting with specific SARS-CoV-2 Spike (S) protein epitopes responsible for recognition by the ACE2 (Angiotensin Converting Enzyme 2) receptor. ACE2 is the host cell receptor protein that is recognized by SARS-CoV-2 Spike (S) protein and mediates viral entry into host cells. Presence of SARS-CoV-2 neutralizing antibodies in serum are indicative of a protective immune response to SARS-CoV-2 due to their ability to interrupt the interaction of Spike (S) protein with ACE2. The presence of neutralizing antibodies is indicative of a protective immune response (immunity). The length of time neutralizing antibodies last in the human body depends on their specific isotype. Neutralizing antibodies may be more prevalent in some specific SARS-CoV-2 vaccines.
The DevLab bio SARS-CoV-2 Neutralizing Antibody (DevNAb) assay is a competitive inhibition enzyme-linked immunosorbent assay intended to qualitatively detect the presence of neutralizing antibodies to the SARS-CoV-2 virus in human serum that may prevent infection or re-infection with SARS-CoV-2. Antibodies to SARS-CoV-2 are generally detectable in blood several days to weeks after initial infection, although the duration of time neutralizing antibodies are present post-infection is not well characterized. As a Laboratory Developed Test (LDT), testing is limited to DevLab, LLC which is certified under the Clinical Laboratory Improvement Amendments of 1988 (CLIA), 42 U.S.C. §263a, and meet the requirements to perform high complexity tests.”
- Bar-On, YM, et al. Science Forum: SARS-CoV-2 (COVID-19) by the numbers. eLife 2020;9:e57309 (https://doi.org/10.7554/eLife.57309)
- Azkur, AK, Akdis, M, Azkur, D, et al. Immune response to SARS‐CoV‐2 and mechanisms of immunopathological changes in COVID‐19. Allergy. 2020; 75: 1564– 1581. (https://doi.org/10.1111/all.14364)
- Official Website of the Centers for Disease Control and Prevention. Coronavirus (COVID-19). (https://www.cdc.gov/coronavirus/2019-ncov/index.html)