So it's important to know what you're doing before you get into it. Lateral flow testing. While it's clear when someone receives a strong single line or a double line, many people don't know what a faint line means on their lateral flow tests. "If both tests are negative and you do not have a high temperature, you're less likely to pass Covid-19 to others and you can go back safely to your normal routine. But even faint lines can indicate the presence of infection. In her study, about 50% of students who tested positive on a rapid test five days after symptom onset were negative in the lab culture tests, leading the researchers to believe that the rapid tests had, in some cases, detected a residual proteinnot an active virus. What does a faint line on a COVID test mean? Our website is not intended to be a substitute for professional medical advice, diagnosis, or treatment. We, Yahoo, are part of the Yahoo family of brands. She is most passionate about stories that cover real issues and spark change. So the bottom line, say our experts: If you're testing positive even with a faint line you should behave as if you are contagious. Michael Mina, MD, PhD, chief medical officer at eMed and former Harvard epidemiology professor, told Verywell the darkness of a line on a positive rapid test is reflective of how much virus a person has, which is the best indicator for their level of infection. At-home tests have an extremely low chance of giving you a false positive, so regardless of whether it seems like you have a lot of virus or just a little, if the test is picking up on it, the best thing is to follow antigen test kit instructions and CDC guidelines, and seek treatment if you think you might need it. Rapid antigen tests look for the virus protein. No matter the circumstances, if you're worried that you could have COVID-19, our experts think your best bet is to repeat your at-home test over a couple of days. The Darkness of Your COVID-19 Rapid Test May Indicate Your Level of Infection. So that first negative test is likely a good sign, but taking an additional test 24 hours later is a great way to confirm the result and rule out errors in testing. Marley Hallis a writer and fact-checker specializing in medical and health information. AN expert has shown how fast the result of a lateral flow test can change from negative to positive, amid the rapid spread of Omicron. Newer PCR tests have a turnaround time of 45 minutes to a few hours, Chan said. The fainter the line, the less virus there is," Peter Chin-Hong, MD, a professor of medicine and infectious disease specialist at the University of California, San Francisco told Health. COVID rapid tests can indicate if a person is infectious and contagious at the exact time of testing. But the self-isolation advice for people with Covid-19 has changed. A PCR test, which detects a virus's genetic material, is more like a forensics detective, who "shows up at the scene of the crime after the crime has already taken place," Mina added. IE 11 is not supported. After carefully inspecting the result, he got . They look for viral genetic material in a respiratory sample, such as a nose or throat swab or a saliva sample. When it comes to testing for COVID-19, RACGP Victoria Chair Dr Anita Muoz has noticed growing confusion among her patients. The opaqueness of the lines also can indicate more, Vail said. If your line is really dark, you might be a super spreader; you might go into a bar and infect 30 people, Mina said. Its not always as simple as positive or negative. With new FDA recommendations on testing, how many times should you test for a definitive result? A negative result on a Healgen Covid-19 Rapid Antigen Test "Essentially, if *any* line appears before the end of the interpretation window (check leaflet, often this is 30 minutes), then this is a . This is a phenomenon called Paxlovid rebound or COVID-19 rebound. How many times do I need to test negative before it's OK to assume I'm virus-free? Still, whether the line or lines are bright or faint, two lines still mean positive, one line still means negative, and the safety precautions remain the same: "Five days of [isolation] and then five days of masking if you have no symptoms," before going back to your normal routine, Vail said. COVID-19 testing. Or you're just getting back from your summer vacation and the back of your throat has a worrisome itch. Testing accuracy depends on when you get tested Both rapid and PCR tests have the potential to be wrong. If you take a rapid test at a pharmacy or at home and its negative, make an appointment for a confirmatory PCR test especially if you have symptoms or have been in close, unmasked contact with someone who has the virus, she added. Scientists can determine that by taking samples from someone who's been infected and trying to grow the virus in a lab . Plus, there are a bunch of other reasons a test line might be darker or lighter that dont have anything to do with the actual amount of viral particles in your body, she said. If you test negative on day 5 or any day after, you can end isolation. So, if you start to feel symptoms like congestion, cough or fever, being able to accurately test yourself for COVID-19 at home can help clarify which illness you might have. A fainter line will probably take longer to show up because it's taking more time for the antibodies to match with pieces of the virus. Well, maybe you might feel better about coming out of your room to see your family, if you wear a mask. Get in touch with Ruby at ruby.gregory@reachplc.com, For more of the latest news from across the capital, head to our homepage, Last month the Omicron variant overtook the Delta variant, and became the most dominant strain in the country. Faint Positive Results Look, How to Order Your Free COVID Tests From the Government. If your rapid COVID test is positive, you should believe it. Also, keep an eye on the expiration date on the rapid tests you're using. If the antibody sticks to part of the virus, it will prevent infection. If you use a home test after its expiration date, you may not get accurate results. By the way, Dr. Russo recommends looking at your test results under good lighting, just to be sure youre getting accurate results. You do not need to isolate and you do not need to book a PCR.". "But if the test is performed correctly, any line no matter how faint is a true positive.". We posed your questions to the experts: Dr. Abraar Karan, infectious disease researcher at Stanford; Meriem Bekliz, virologist at the University of Geneva; and Dr. Preeti Malani, professor of medicine at the University of Michigan. A spokesperson for Abbott, which produces the widely available BinaxNOW COVID-19 Antigen Self Test, told Verywell that it is most important for people to know that if a second line shows up in addition to the control line, to any extent, it means that the test is positive and the person has potential to transmit the virus. While there is currently no requirement to test out of isolation after having COVID, Chicago's top doctor has warned that the new BA.5 omicron subvariant is making people test positive longer . Thomas Russo, M.D., a professor and the chief of infectious diseases at the University at Buffalo in New York, agrees. This is also why a negative antigen test after five days of isolation likely means that the person is no longer contagious, Dr. Chin-Hong added. Covid-19 testing facility overseer Dr Sally Shaw told 3AW a faint line should be considered a positive result on a RAT if the person has symptoms. "A security guard works by recognizing that that something bad is happening right in that moment, and is able to act immediately.". While that's reassuring, there wasn't agreement among our experts about exactly what to do. The latest vaccine data shows antibodies drop off fairly steeply in the first few months after the second dose. Essentially, a positive result is still a positive result, no matter how it looksand you should follow the same COVID safety precautions, regardless. If You've Never Had COVID Are You More Susceptible to Variants? Photo by Getty. A positive result means you almost certainly have Covid. I also wanted to know more about what the tests are actually measuring, what that line actually means and whether a darker or lighter positive line on a COVID-19 test can tell you anything about your individual infection. Goodbye, brain scrapers. Coronavirus FAQ: I'm confused by the new testing advice! Potentially, we do need a panel of tests that are looking at how antibodies bind to different spikes since spikes differ from variant to variant.. Here's what you need to know about taking a rapid COVID-19 test and figuring out what your results mean even if they're a little faint or hard to parse. This probably means that the person is not infected with the coronavirus. The information in this article is current as of the date listed, which means newer information may be available when you read this. If you have been exposed to a person with COVID, the right time to be tested is within three to five days. She uses her experience in medical research to ensure content is accurate across multiple Dotdash Meredith brands. It is now possible to end self-isolation . Does this mean I could have COVID-19? Write an article and join a growing community of more than 160,300 academics and researchers from 4,571 institutions. They may even have symptoms for a few days before turning positive. You didnt do the best job taking your test, which happens. Infectious Diseases (except HIV/AIDS); 2022. doi:10.1101/2022.02.01.22269931. Just because a faint line might mean the impending end of an infection for one person, it just may mean user errorlike if a person didn't swab their nose correctlyfor another. Sarah Jacoby is a health reporter at TODAY. If the line is fainter, the patient is likely to be less sick, less infectious, or might be nearing the end of infection, Vail said. It's especially important to test before gathering indoors with people who are at a higher risk for severe COVID-19 symptoms, such as older adults, people who are immunocompromised and children who are too young to be vaccinated, the CDC says. Once you have tested positive and your body starts clearing the virus, a negative rapid test should be a pretty good indication you're no longer infectious, so long as you follow the test protocols correctly and wait an appropriate amount of time before testing. But what does a faint line on a COVID test after 15 minutes mean? In some cases, retesting the original sample may give more confidence of an infection with SARS-CoV-2. "A faint line on a COVID test means the test is positive," says infectious. For those who do test positive, the time it takes for the line to appear on the COVID test and what that line might look likefrom barely visible to bright and opaquecan vary. Julie Garcia is a features reporter at the Houston Chronicle focusing on health, fitness and outdoors. With school starting, regular COVID testing will likely become more common for adults and children. Also, if people test multiple times over the span of their infection and see the lines growing fainter, that's probably a good sign that they're almost done with their infection, Dr. Chin-Hong added. I think it might be helpful in little environments like that, but we can't use [line intensity] for the large public. The way that at-home tests currently work, Dr. Vail explained, is to give the person a yes or no response to the question of whether or not they have the virus in their bodies. People who have active COVID symptoms should wait until theyve fully recovered and are out of isolation before considering making a vaccine appointment at a pharmacy, clinic or their doctors office, said Dr. Galant Chan, infectious disease physician at Baylor St. Lukes Hospital.