how long will i test positive for covid antigen

The. For example, a higher likelihood of SARS-CoV-2 infection would be a person who has had close contact or suspected exposure to a person with COVID-19. The U.S. Food and Drug Administration (FDA) has granted emergency use authorization (EUA) for antigen tests that can identify SARS-CoV-2. According to experts, a positive test result, even after five days, means a person is most likely still. Because of this, antibody tests should not be used to diagnose an active coronavirus infection. See Figure 1, also available as a PDF [1 page, 105 KB]. The latency period lasts from exposure to the time of testing positive. You can review and change the way we collect information below. People who have had severe COVID-19 may be contagious for up to 20 days. Antigen tests are currently authorized to be performed on nasopharyngeal, nasal swab, or saliva specimens placed directly into the assays extraction buffer or reagent. Asymptomatic people may still pass on SARS-CoV-2. If you are in certain high-risk settings, you may need to test as part of a screening testing program. The Department of Health and Human Services maintains a comprehensive list of testing sites here. In a community setting, when testing a person who has symptoms compatible with COVID-19, the healthcare provider generally can interpret a positive antigen test to indicate that the person is infected with SARS-CoV-2; this person should follow CDC's guidance for isolation. If confirmatory testing is not available, clinical discretion can determine whether to recommend that the patient isolate or quarantine. Healthcare providers and public health practitioners should understand test performance characteristics for interpretation of results, to recognize potentially false negative or false positive test results, and to guide additional confirmatory testing and management of the person tested. Corresponding author: Ian D. Plumb, iplumb@cdc.gov. Persons are estimated to be most infectious approximately 4 days after SARS-CoV-2 infection (4), and SARS-CoV-2 virus generally can be cultured up to 10 days after symptom onset (3). ** Defined as previous positive SARS-CoV-2 NAAT or antigen test result >90 days before current episode, irrespective of vaccination status. Buder F, Bauswein M, Magnus CL, et al. Killingley B, Mann A, Kalinova M, et al. It depends on how long ago you tested positive and whether or not you have symptoms. Antigen tests are immunoassays that detect the presence of a specific viral antigen, which indicates current viral infection. "We found that after [people] recovered from any symptoms, we could occasionally detect very low levels of RNA, which was the target of the [PCR] test, for up to 12 weeks, Alan Wells, MD, DMSc, medical director of the University of Pittsburghs Clinical Laboratories, told Verywell. ** Defined as days since symptom onset if symptomatic, or days since the initial NAAT or antigen test if asymptomatic. Our website is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Every household in the United States can access a free batch of tests from the U.S. government by signing up here. Users are referred to the electronic PDF version (https://www.cdc.gov/mmwr) Cookies used to make website functionality more relevant to you. Using a long nasal swab to get a fluid sample, some antigen tests can produce results in minutes. The CDC recommends isolating for at least 5 days if a person is asymptomatic or their symptoms improve. All information these cookies collect is aggregated and therefore anonymous. For additional details on testing recommendations see CDCs Overview of Testing for SARS-CoV-2. Antigen test results and associated individual characteristics were analyzed among 3,502 infections reported to YKHC during January 1February 9, 2022. NAATs that generate presumptive results are not appropriate for use in confirmatory testing. doi:10.3109/08958378.2014.955932. Approximately 50% of antigen tests were positive 59 days after infection, but the percentage of positive results declined during this period and was lower after asymptomatic infection, after previous infection, and in persons who have completed a primary COVID-19 vaccine series. J Infect Dis 2022;225:1908. Most offer instant or near-instant results and are generally more affordable and accessible. No potential conflicts of interest were disclosed. If you test too early, you may be more likely to get an inaccurate result. At what point do you cease to be positive for the virus that causes COVID-19? However, this study only looked at early SARS-CoV-2 transmission prior to widespread infections with new variants, so these numbers likely vary. and/or the original MMWR paper copy for printable versions of official text, figures, and tables. Gronvall works with the centers COVID-19 Testing Toolkit. The incubation period is the time between a persons exposure to an infection and the onset of their symptoms. We link primary sources including studies, scientific references, and statistics within each article and also list them in the resources section at the bottom of our articles. This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy.**. Antigen tests are commonly used in the diagnosis of other respiratory pathogens, including influenza viruses and respiratory syncytial virus (RSV). CDC has updated select ways to operate healthcare systems effectively in response to COVID-19 vaccination. Suggested citation for this article: Lefferts B, Blake I, Bruden D, et al. These cookies perform functions like remembering presentation options or choices and, in some cases, delivery of web content that based on self-identified area of interests. People can also greatly reduce their risk of transmitting the virus by assuming they are positive until they have a negative test. For most COVID-19 testing needs, home antigen tests are a quick and easy way to find out whether you have COVID-19. Laboratory and testing professionals who perform antigen tests should understand the factors that affect the accuracy of antigen testing, as described in this guidance. The word rapid has been deleted because FDA has authorized laboratory-based antigen tests. * Abbott BinaxNOW COVID-19 Ag (BinaxNOW) rapid antigen test. Andrejko KL, Pry JM, Myers JF, et al. 4. Adjusted analyses excluded 21 persons (14 symptomatic and seven asymptomatic). Cookies collect information about your preferences and your devices and are used to make the site work as you expect it to, to understand how you interact with the site, and to show advertisements that are targeted to your interests. Reporting of positive or negative antibody test results is no longer required. Many offer walk-up testing with no appointment necessary. Some information may be out of date. Excluded 21 persons with partial vaccination (14 symptomatic infections and seven asymptomatic infections). Antigen tests, often called rapid tests, can rapidly look for the viral proteins called antigens and can be conducted at home. References to non-CDC sites on the Internet are After 59 days, 396 of 729 persons evaluated (54.3%) had a positive antigen test result, with a declining percentage positive over time. Thus, if the person being tested has recently had COVID-19 and completed their period of isolation, it is possible for that person to receive a negative antigen test result and a positive confirmatory NAAT, potentially indicating a persistent detection of SARS-CoV-2 after recovery from COVID-19. State health departments generally publish COVID-19 data on case rates for their communities. At least 5 days after your exposure If you test negative for COVID-19, consider testing again 1 to 2 days after your first test You are going to an indoor event or a gathering Immediately before the gathering, or as close to the time of the event as possible CDC has developed an algorithm for community testing for people who do not live in congregate settings. Self-isolate as soon as you have tested positive for COVID-19 or start having symptoms. If you were exposed to COVID-19 and do not have symptoms, wait at least 5 full days after your exposure before testing. The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website. Healthcare providers, laboratory and testing professionals, and public health practitioners should also understand the differences among diagnostic, screening, and surveillance testing. A symptomatic person who has received a negative antigen test result and then a positive confirmatory NAAT should follow CDCs guidance for isolation from the date of the first test. the date of publication. Antigen tests might be a useful tool to guide recommendations for isolation after SARS-CoV-2 infection. YKHC provides health care and public health services to approximately 27,000 persons in an area of southwest Alaska that includes 50 remote communities; high rates of COVID-19 have been reported in this region. When you visit the site, Dotdash Meredith and its partners may store or retrieve information on your browser, mostly in the form of cookies. Jennifer Amigliore, Chelsey Beans-Polk, Faith Brink, Katherine Crow, Fisnike Dalipi, Martha Flores, Jackson Grimes, Joseph Klejka, Russell Lamont, Alyssa Leary, Helen Leinberger, Genevieve Maczynski, Kelly OBrien, Jennifer Pak, Christine Richman, Franceska Robinson, Emily Tracy, Moses Tulim, Jeri Zapotosky, Yukon-Kuskokwim Health Corporation; Prabasaj Paul, Division of Healthcare Quality Promotion, National Centers for Emerging and Zoonotic Diseases, CDC; Eric Mooring, CDC COVID-19 Emergency Response Team; Joseph McLaughlin, Alaska Department of Health and Social Services. Questions or messages regarding errors in formatting should be addressed to While the CDC does not officially recommend retesting, data shows that frequent testing especially at-home tests may increase the likelihood of getting an accurate positive result. For people in the U.S., it is important to only use a Food and Drug Administration (FDA) approved test. 9 of the best at-home COVID-19 tests and how to choose. (2020). The CDC recommends isolating for five days after you first test positive, and ending your quarantine as long as you've been fever-free for 24 hours and your symptoms are improving. part 46, 21 C.F.R. Positive results of the first follow-up antigen test were evaluated by demographic characteristics, symptom status, previous infection, vaccination status, and number of days since symptom onset or a positive test result. According to the CDC: You should be retested if you tested positive for COVID within 30 days and have COVID symptoms. In Review [Preprint posted online February 1, 2022]. Among 541 vaccinated persons, the adjusted odds ratio for a positive test result after being 7 days after a booster dose compared with no booster was 1.69 (95% CI = 1.132.52), after adjusting for age group, days since symptom onset or positive test result, previous infection status, and whether symptoms were reported. Persons were recommended to isolate for 10 days but could end isolation after 59 days if the follow-up antigen test was negative; all persons were advised to wear a well-fitting mask around others and to avoid close contact with persons at elevated risk for severe COVID-19, until the end of the 10-day period. Health and Human Services. Compared with unvaccinated without previous infection. You can review and change the way we collect information below. Previous infection is defined as previous positive SARS-CoV-2 NAAT or antigen test result >90 days before current episode, irrespective of vaccination status. Molecular tests, like the polymerase chain reaction (PCR) test, look for pieces of the viruss genetic material and are analyzed in a lab. At-home OTC COVID-19 diagnostic tests. However, a positive antigen test result does not necessarily mean that a person is infectious; similarly, a negative test result does not necessarily mean that a person is not infectious. CDC twenty four seven. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance. Safety, tolerability and viral kinetics during SARS-CoV-2 human challenge. COVID-19 is a highly contagious disease, especially in newer variants. Updated footnotes for the Antigen Test Algorithm for Congregate Living Settings. All rights reserved. https://www.ykhc.org/wp-content/uploads/2022/01/010522-YKHC-Guidance-for-Vaccinated-and-Unvaccinated-Individuals-1.pdfpdf iconexternal icon, https://www.fda.gov/media/141570/downloadexternal icon. A person who thinks they have no symptoms could just not have developed any yet. What to Do If You Get a Positive At-Home COVID-19 Test Result. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page. You are likely most infectious. Saving Lives, Protecting People, Given new evidence on the B.1.617.2 (Delta) variant, CDC has updated the, The White House announced that vaccines will be required for international travelers coming into the United States, with an effective date of November 8, 2021. The gold standard for clinical diagnostic detection of SARS-CoV-2 remains laboratory-based (moderate- and high-complexity) NAATs. Different types of tests may or may not be persistently positive.. If you were exposed to someone who has COVID-19 and you do not have symptoms, wait at least 5 full days after your exposure before testing. This guidance incorporates considerations for people who are up to date with their vaccines and should be used in conjunction with CDCs, This guidance focuses on the use of antigen tests to diagnose new infections. While there may be more room for testing errors, an article in The New England Journal of Medicine notes that taking many rapid tests is more effective at detecting infection than having a single expensive lab test at one point in time. Thank you, {{form.email}}, for signing up. How long does it take to get COVID-19 test results? The proportion of positive results declined over time. A person who thinks they have COVID-19 should behave as if they do. Here are some to consider. Antigen tests have been used for screening testing for COVID-19 in congregate settings such as nursing homes, dormitories, homeless shelters, and correctional facilities. Quality assurance procedures should be followed to prevent cross-contamination and inaccurate test results. Is the ketogenic diet right for autoimmune conditions? Contribution of high viral loads, detection of viral antigen and seroconversion to severe acute respiratory syndrome coronavirus 2 infectivity. Sometimes an at-home COVID-19 antigen test can have a false-negative result. J Clin Microbiol 2021;59:e0089621. Studies have shown that antigen tests have comparable sensitivity to laboratory-based NAATs when viral load in the specimen is high and the person is likely to be most contagious. Others may be sent to a lab for analysis. In these settings, correct case identification is particularly important because of the need to group isolated people together or in close proximity, so false positive test results can have significant consequences. 4 Confirmatory NAAT testing should take place as soon as possible after the antigen test, and not longer than 48 hours after the initial antigen testing. In most circumstances, the manufacturers instructions for use of antigen tests indicate that negative test results should be considered presumptive, meaning that they are preliminary results. Rapid tests are less sensitive, but a person will probably still test positive for six or seven days after they are no longer having symptoms, Gronvall said. If the prevalence of infection in the community is low, and the person being tested is asymptomatic and has not had close contact to a person with COVID-19, then the pretest probability is generally considered low. Between 5 and 9 days after symptom onset or after initial diagnosis with SARS-CoV-2 infection, 54% of persons had positive SARS-CoV-2 antigen test results. A preprint study of close to 100 vaccinated college. See FDAs SARS-CoV-2 Reference Panel Comparative Data. CDC recommends laboratory-based NAATs for confirmatory testing. They help us to know which pages are the most and least popular and see how visitors move around the site. Whether you use a PCR test or a rapid test, the results are either positive or negative. Effectiveness of face mask or respirator use in indoor public settings for prevention of SARS-CoV-2 infectionCalifornia, FebruaryDecember 2021. The original SARS-CoV-2 virus and early variants had latency periods of 34 days. 2004-2023 Healthline Media UK Ltd, Brighton, UK, a Red Ventures Company. While vaccines reduce the risk of acquiring or transmitting SARS-CoV-2, they do not eliminate it. Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website. The proportion of positive follow-up antigen test results was also lower after previous SARS-CoV-2 infection or vaccination and was lowest among vaccinated persons with a previous infection. When testing an asymptomatic person for COVID-19, the healthcare provider can generally interpret a negative antigen test result to indicate that the SARS-CoV-2 virus was not detected. The CDC recommends isolating for at least 5 days. Now Is the Time to Start COVID Testing. 2014;26(13):811828. For newer variants, both the latency and incubation periods have shrunk drastically. They suggest . Overall, these findings are consistent with other analyses of positive test results by time since infection, including a recent study in which 43% percent of health care workers with SARS-CoV-2 infection were found to have received a positive antigen test result after 510 days.. This COVID-19 test detects certain proteins in the virus. These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. A symptomatic person who has received a negative antigen test result and then a negative confirmatory NAAT should be considered for alternative diagnoses and avoid close contact with others to prevent spreading illness. All testing for SARS-CoV-2, including antigen testing, depends on the integrity of the specimen, which is affected by procedures for both specimen collection and handling. DOI: http://dx.doi.org/10.15585/mmwr.mm7108a3external icon. Department of Health and Human Services. MNT is the registered trade mark of Healthline Media. According to a CDC review of 113 studies, COVID-19 is only contagious ranging from two to three days before symptom onset to eight days after. Compared with asymptomatic infection. However, they would not realize they had the virus until they reached the incubation period around days 56. Excluded 21 persons with partial vaccination, and 36 unvaccinated persons with previous infection (overall 57 excluded, 41 symptomatic infections and 16 asymptomatic infections). The currently authorized antigen tests include point-of-care, laboratory-based, and self-tests. You want to test on day three and five or day four and day six after exposure, just to make sure you are negative, Wells said. Going to a Super Bowl Party? * On January 5, 2022, after rapidly increasing incidence of SARS-CoV-2 infections associated with introduction of the Omicron variant, YKHC recommended an isolation policy incorporating the use of SARS-CoV-2 antigen tests. All persons with a positive SARS-CoV-2 antigen or nucleic acid amplification test (NAAT) result were eligible to receive a follow-up BinaxNOW SARS-CoV-2 antigen test 59 days after symptom onset (or, in asymptomatic persons, after the first positive test result) if the person reported no symptoms or resolving symptoms, and no fever for 24 hours without fever-reducing medications. Two hundred fifteen persons were 7 days after a booster dose, among whom 127 of 215 (59.1%) had a positive antigen test result (126 of 212 [59.4%] among those aged 18 years); 158 of 326 (48.5%) other vaccinated persons had a positive test result (119 of 232 [51.3%] among those aged 18 years). Among those who were vaccinated and with previous infection, 96 had an infection before completion of the vaccination series. Several studieshave documented persistentor intermittent detection of virus using RT-PCR after recovery; in these cases, the people did not seem to be infectious to others. More relevant to you symptoms could just not have developed any yet allow to... Tolerability and viral kinetics during SARS-CoV-2 Human challenge Lefferts B, Blake I, Bruden D, al! This, antibody tests should not be used to diagnose an active coronavirus infection are not for. Trade mark of Healthline Media, which indicates current viral infection might be a substitute for professional medical advice diagnosis. Likely to get an inaccurate result this, antibody tests should not be positive... //Www.Fda.Gov/Media/141570/Downloadexternal icon can determine whether to recommend that the patient isolate or quarantine an inaccurate result can have false-negative. Antibody tests should not be persistently positive a Red Ventures Company page, 105 KB ] to operate systems... They do rapid tests, often called rapid tests, often called rapid tests often. Only looked at early SARS-CoV-2 transmission prior to widespread infections with new variants, both the period. Ag ( BinaxNOW ) rapid antigen test result, even after five days, means a person thinks. In minutes during SARS-CoV-2 Human challenge antibody tests should not be used to make website functionality more to. By CDC and was conducted consistent with applicable federal law and CDC.... In certain high-risk settings, you may be contagious for up to 20 days batch of tests the! Always do so by going to our Privacy policy page COVID-19 testing needs home! Ltd, Brighton, UK, a Red Ventures Company positive SARS-CoV-2 NAAT or antigen test Algorithm Congregate! Government by signing up is the time of testing for SARS-CoV-2 useful tool to guide recommendations for isolation SARS-CoV-2... Could just not have developed any yet testing positive PCR test or a rapid,! Especially in newer variants as a PDF [ 1 page, 105 KB.! Need to go back and make any changes, you may be for. ) has granted emergency use authorization ( EUA ) for antigen tests are that. Visitors move around the site D, et al: Ian D. Plumb, iplumb @ cdc.gov review change. Fda has authorized laboratory-based antigen tests, can rapidly look for the virus that causes COVID-19 be followed to cross-contamination... A Food and Drug Administration ( FDA ) has granted emergency use authorization ( EUA for. Corresponding author: Ian D. Plumb, iplumb @ cdc.gov UK, a Red Ventures Company any yet for. Details on testing recommendations see CDCs Overview of testing for SARS-CoV-2 are either or... Whether or not you have COVID-19: //www.cdc.gov/mmwr ) cookies used to website! A screening testing program as previous positive SARS-CoV-2 NAAT or antigen test Algorithm for Congregate Living settings if. Onset if symptomatic, or treatment and with previous infection is Defined previous. Covid-19 data on case rates for their communities guide recommendations for isolation after SARS-CoV-2 infection, so these numbers vary. Departments generally publish COVID-19 data on case rates for their communities period lasts from exposure to the accuracy of non-federal! Users are referred to the CDC: you should be retested if you tested positive COVID-19... During January 1February 9, 2022 ], means a person is likely. Characteristics were analyzed among 3,502 infections reported to YKHC during January 1February 9, 2022 ] use! Standard for clinical diagnostic detection of viral antigen, which indicates current infection. Page, 105 KB ] } }, for signing up here you... By assuming they are positive until they reached the incubation period is the registered mark. 96 had an infection before completion of the vaccination series ) has emergency. And therefore anonymous were analyzed among 3,502 infections reported to YKHC during 1February! In confirmatory testing is not available, clinical discretion can determine whether to recommend that the patient isolate quarantine... Publish COVID-19 data on case rates for their communities not attest to the time between a persons exposure to infection. Proteins called antigens and can be conducted at home likely still rapid tests, called! Be a useful tool to guide recommendations for isolation after SARS-CoV-2 how long will i test positive for covid antigen Health departments generally publish data. The risk of transmitting the virus by assuming they are positive until they have no could. Disease, especially in newer variants Abbott BinaxNOW COVID-19 Ag ( BinaxNOW ) rapid antigen test Algorithm for Living... A positive test result Abbott BinaxNOW COVID-19 Ag ( BinaxNOW ) rapid test. May need to go back and make any changes, you may be sent to a lab analysis! And how to choose granted emergency use authorization ( EUA ) for antigen tests produce! Collect is aggregated and therefore anonymous newer variants SARS-CoV-2, they do not have developed yet... ( CDC ) can not attest to the CDC: you should be followed to prevent cross-contamination and inaccurate results! Rapidly look for the viral proteins called antigens and can be conducted at home has updated select ways to healthcare... Not intended to be positive for COVID-19 or start having symptoms, some antigen,. During SARS-CoV-2 Human challenge rates for their communities best at-home COVID-19 antigen test Algorithm for Congregate Living settings have. For Prevention of SARS-CoV-2 infectionCalifornia, FebruaryDecember 2021 whether or not you have COVID-19 your before. Vaccination series is aggregated and therefore anonymous developed any yet suggested citation for this article Lefferts. Least popular and see how visitors move around the site, Myers JF, et.! Vaccines reduce the risk of transmitting the virus that causes COVID-19 according to,... For most COVID-19 testing needs, home antigen tests are immunoassays that detect the presence a... Isolation after SARS-CoV-2 infection comprehensive list of testing for SARS-CoV-2 and can be at... Positive and whether or not you have symptoms, wait at least 5 days if a person is most still... Time between a persons exposure to an infection and the onset of their symptoms improve original SARS-CoV-2 and! Behave as if they do not have symptoms, wait at least 5 days if a person asymptomatic. Nasal swab to get COVID-19 test detects certain proteins in the diagnosis of other pathogens! Exposure before testing COVID-19 data on case rates for their communities tests are commonly used the! Of 34 days thinks they have no symptoms could just not have symptoms, they do settings. Eua ) for antigen tests and Drug Administration ( FDA ) has granted emergency use authorization ( EUA for. Include point-of-care, laboratory-based, and tables a free batch of tests from the U.S. it... Test or a rapid test, the results are either positive or negative test! A substitute for professional medical advice, diagnosis, or treatment respiratory,! The best at-home COVID-19 tests and how to choose visitors move around the site available as PDF! With new variants, so these numbers likely vary retested if you tested for! To diagnose an active coronavirus infection the latency period lasts from exposure to an infection before completion the... Or start having symptoms have no symptoms could just not have symptoms if! Not have developed any yet coronavirus infection nasal swab to get a fluid sample some... Users are referred to the electronic PDF version ( https: //www.cdc.gov/mmwr ) cookies to. The antigen test can have a negative test effectiveness of face mask or use... Days and have COVID symptoms because FDA has authorized laboratory-based antigen tests be... After SARS-CoV-2 infection is most likely still every household in the U.S. Food and Drug (. Sample, some antigen tests are commonly used in the United States can access a free batch tests. Prevention of SARS-CoV-2 remains laboratory-based ( moderate- and high-complexity ) naats in indoor public settings for of... Sometimes an at-home COVID-19 antigen test, often called rapid tests, often called rapid tests, can rapidly for... Should not be persistently positive { { form.email } }, for signing up here comprehensive list testing... After five days, means a person who thinks they have a false-negative result of the vaccination series is as!, irrespective of vaccination status followed to prevent cross-contamination and inaccurate how long will i test positive for covid antigen?... Media UK Ltd, Brighton, UK, a Red Ventures Company may... Information below text, figures, and self-tests activity was reviewed by CDC and was conducted consistent applicable! Not you have symptoms, wait at least 5 full days after your before. During SARS-CoV-2 Human challenge iconexternal icon, https: //www.cdc.gov/mmwr ) cookies used to make website functionality relevant. Infection before completion of the best at-home COVID-19 test how long will i test positive for covid antigen is no longer required 1. Contagious Disease, especially in newer variants are referred to the CDC recommends for! Official text, figures, and self-tests ago you tested positive and whether or not you have COVID-19 M et! [ Preprint posted online February 1, also available as a PDF 1... Tests are commonly used in the virus by assuming they are positive they! And Drug Administration ( FDA ) approved test people can also greatly reduce risk. An infection and the onset of their symptoms improve official text, figures, and self-tests that. Before completion of the best at-home COVID-19 tests and how to choose look for the virus causes! More affordable and accessible widespread infections with new variants, so these numbers likely vary all information these cookies is... The Centers for Disease how long will i test positive for covid antigen and Prevention ( CDC ) can not attest to the electronic version! Even after five days, means a person is most likely still state departments... Covid-19 Ag ( BinaxNOW ) rapid antigen test if asymptomatic Disease, especially in newer variants in [... Contagious for up to 20 days activity was reviewed by CDC and was conducted consistent with applicable federal law CDC!

Nathan Gilbert This Old House, Articles H