COVID-19 testing

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COVID-19 pandemic
Scientifically accurate atomic model of the external structure of SARS-CoV-2. Each "ball" is an atom.
Scientifically accurate atomic model of the external structure of SARS-CoV-2. Each "ball" is an atom.
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CDC 2019-nCoV Laboratory Test Kit.jpg
The US CDC's COVID-19 laboratory test kit

COVID-19 testing involves analyzing samples to assess the current or past presence of SARS-CoV-2, the virus that cases COVID-19 and is responsible for the COVID-19 pandemic. The two main types of tests detect either the presence of the virus or antibodies produced in response to infection.[1][2] Molecular tests for viral presence through its molecular components are used to diagnose individual cases and to allow public health authorities to trace and contain outbreaks. Antibody tests (serology immunoassays) instead show whether someone once had the disease.[3] They are less useful for diagnosing current infections because antibodies may not develop for weeks after infection.[4] It is used to assess disease prevalence, which aids the estimation of the infection fatality rate.[5]

Individual jurisdictions have adopted varied testing protocols, including whom to test, how often to test, analysis protocols, sample collection and the uses of test results.[6][7][8] This variation has likely significantly impacted reported statistics, including case and test numbers, case fatality rates and case demographics.[9][10][11][12] Because SARS-CoV-2 transmission occurs days after exposure (and before onset of symptoms), there is an urgent need for frequent surveillance and rapid availability of results.[13]

Test analysis is often performed in automated, high-throughput, medical laboratories by medical laboratory scientists. Rapid self-tests and point-of-care testing are also available and can offer a faster and less expensive method to test for the virus although with a lower accuracy.[14][15]

  1. ^ "Coronavirus Disease 2019 (COVID-19)". U.S. Centers for Disease Control and Prevention (CDC). 11 February 2020. Archived from the original on 14 March 2020. Retrieved 9 June 2020.
  2. ^ Kobokovich A, West R, Gronvall G. "Global Progress on COVID-19 Serology-Based Testing". Johns Hopkins Center for Health Security. Archived from the original on 9 June 2020. Retrieved 9 June 2020.
  3. ^ Kubina R, Dziedzic A (June 2020). "Molecular and Serological Tests for COVID-19 a Comparative Review of SARS-CoV-2 Coronavirus Laboratory and Point-of-Care Diagnostics". Diagnostics. 10 (6): 434. doi:10.3390/diagnostics10060434. PMC 7345211. PMID 32604919.
  4. ^ "Test for Past Infection". U.S. Centers for Disease Control and Prevention (CDC). 2020. Archived from the original on 16 May 2020. Retrieved 19 May 2020. Antibody blood tests, also called antibody tests, check your blood by looking for antibodies, which show if you had a previous infection with the virus. Depending on when someone was infected and the timing of the test, the test may not find antibodies in someone with a current COVID-19 infection.
  5. ^ Cite error: The named reference JAMA_antibody was invoked but never defined (see the help page).
  6. ^ Brotschi M (7 March 2020). "Bund sucht nicht mehr alle Corona-Infizierten" [The federal government is no longer looking for all those infected with corona]. Der Bund (in German). ISSN 0774-6156. Archived from the original on 29 March 2020. Retrieved 9 June 2020.
  7. ^ Van Beusekom M (24 March 2020). "Italian doctors note high COVID-19 death rate, urge action". CIDRAP News. Archived from the original on 9 June 2020. Retrieved 9 June 2020.
  8. ^ Otmani M (22 March 2020). "COVID-19: First results of the voluntary screening in Iceland". Nordic Life Science. Archived from the original on 29 March 2020. Retrieved 9 June 2020.
  9. ^ Ward D (April 2020). "Sampling bias: explaining wide variations in COVID-19 case fatality rates". Preprint. Bern, Switzerland: WardEnvironment. doi:10.13140/RG.2.2.24953.62564/1.
  10. ^ Henriques M (2 April 2020). "Coronavirus: Why death and mortality rates differ". BBC News. Archived from the original on 2 April 2020. Retrieved 9 June 2020.
  11. ^ Ward D (May 2020). Sampling Bias: Explaining Variations in Age Distributions of COVID-19 Cases. Technical Report (Report). WardEnvironment. doi:10.13140/RG.2.2.27321.19047/2.
  12. ^ "Why More Younger People Are Testing Positive for COVID-19". Time. Archived from the original on 26 February 2021. Retrieved 18 August 2020.
  13. ^ Mina MJ, Parker R, Larremore DB (November 2020). "Rethinking Covid-19 Test Sensitivity - A Strategy for Containment". The New England Journal of Medicine. 383 (22): e120. doi:10.1056/NEJMp2025631. PMID 32997903. S2CID 222158786.
  14. ^ "Antigen-detection in the diagnosis of SARS-CoV-2 infection". www.who.int. Retrieved 12 July 2022.
  15. ^ CDC (11 February 2020). "Guidance for Antigen Testing for SARS-CoV-2 for Healthcare Providers Testing Individuals in the Community". Centers for Disease Control and Prevention. Retrieved 12 July 2022.