Antibody testing for COVID-19 is now widely available in New York City. Unlike the polymerase chain reaction test used to detect coronavirus from the infamous nasal and throat swab, the antibody test does not determine whether you currently have the disease. Instead, it can detect antibodies against COVID-19 present in blood and determine whether you had COVID-19 in the past. The body produces antibodies to facilitate the destruction of invading pathogens, such as SARS-CoV-2, by immune cells. Antibody tests are designed to detect two specific types of antibodies, IgG and/or IgM. Patients with COVID-19 develop IgM antibodies shortly after the virus attacks. IgM antibodies are then replaced with IgG antibodies which become detectable in the blood of COVID-19 patients approximately ten days after they become symptomatic. While all patients recovering from COVID-19 develop antibodies against SARS-CoV-2, scientists and health authorities are debating whether the presence of antibodies protects people from reinfection. In addition, antibody levels may wane over time effectively erasing any acquired immunity. For instance, a 2006 study showed that antibodies against SARS-CoV, a coronavirus closely related to the virus that ravaged the world in the past months, lasted for several months to two years, although all study participants had low antibody levels after about fifteen months. While the longitudinal profile of antibodies against SARS-CoV-2 is still unclear, a predictive modeling study showed that, in the absence of recurrent vaccination, short-term immunity (~ten months) against SARS-CoV-2 would lead to annual outbreaks of the novel coronavirus, while long-term immunity (~two years) would cause biennial outbreaks. However, it is critically important to conduct antibody tests to better understand the impact of the novel coronavirus on communities that are heavily affected by it.
Over a two-week period in May, the NYC Department of Health conducted a citywide antibody survey and tested approximately 70,000 NYC residents for the presence of antibodies against SARS-CoV-2. Launched in partnership with BioReference Laboratories, the study was designed to help health authorities better understand the spread of COVID-19, how the body responds to the virus that causes it, how often the virus causes an infection with symptoms, the frequency of specific symptoms, and risk factors for this disease. “For New York, a city that has been seriously impacted by the COVID-19 pandemic, this type of information will be of great value in helping healthcare professionals to analyze the presence and progression of the disease in order to identify at risk populations for possible early intervention,” said Jon R. Cohen, M.D., the Executive Chairman of BioReference Laboratories, in a press release posted on the BioReference website on May 7. The antibody test was offered to NYC residents for free with testing sites available in all five boroughs. Several members of our editorial board participated in this antibody survey at the testing site closest to The Rockefeller University campus in Long Island City, Queens. Located inside a repurposed warehouse, the testing site prioritized the safety of study participants with temperature scans at the entrance and free personal protective equipment (PPE). Several blood draw stations were spaced out to allow for a distance of at least six feet between them. Colorful tape on the floor indicated the direction of foot traffic and prevented crowding. The nurses, in full PPE, drew blood through vein puncture and collected one tube of blood per participant. For those who filled out the screening survey online, the entire process could take less than ten minutes. To determine the presence of antibodies in blood samples, BioReference used the Roche Elecsys test with 99.8% specificity and 100% sensitivity. The results of the test were available online on the BioReference portal 24-48 hours after the test was administered. As of this writing, the NYC Department of Health paused the recruitment of new participants for this survey. However, you can still access antibody testing in NYC, often with $0 co-pay for those with private health insurance, Medicaid, or Medicare. Some testing sites might also provide free antibody tests for those without health insurance. For example, Mount Sinai is looking for volunteers to donate convalescent plasma used to treat patients with COVID-19. They are screening the members of the public who have previously had the symptoms of COVID-19 and waiving fees for antibody tests. To participate, fill out this survey. For the full list of testing sites available near you, visit the New York State Department of Health website.