COVID-19 testing

From Simple English Wikipedia, the free encyclopedia
CDC 2019-nCoV Laboratory Test Kit.jpg
The US CDC's COVID‑19 laboratory test kit

COVID-19 testing can help find the SARS-CoV-2 virus. There are two types of test; one can find the virus (i.e. Polymerase chain reaction, also called PCR) and the other that can find antibodies produced in response to infection.

An accurate mortality rate of the disease and the level of herd immunity in the population can be found from the results of these tests. However, it is still not known how long immunity will last, and how effective it will be.[1]

Due to limited testing, as of March 2020, no countries had reliable data of the virus.[2]

Test methods[change | change source]

Detection Timing[change | change source]

  1. Viral burden (the amount of virus) measured in the respiratory tract declines after the start of illness.[3]
  2. At this time, replication-competent virus has not been successfully cultured more than nine days after the illness.[4]
  3. As isolating replication-competent virus lowers, anti-SARS-CoV-2 IgM and IgG can be found in an increasing number of persons recovering from infection.[5]
  4. Attempts to grow the virus from upper respiratory specimens have been largely unsuccessful[6]
  5. Following recovery from the illness, many patients no longer have detectable viral RNA in upper respiratory.[7]
  6. No clear link has been seen between length of illness and length of recovery. [8]
  7. Infectious virus has not been grown from urine or feces;[9] these possible sources have a very small risk of spreading infection.

WHO methods[change | change source]

Diagnostic tests accepted by the WHO for procurement
Date listed Product name Manufacturer
3 April 2020 Cobas SARS-CoV-2 qualitative assay for use on the cobas 6800/8800 Systems Roche Molecular Systems
7 April 2020 Coronavirus (COVID-19) genesig rtPCR assay Primerdesign
9 April 2020 Abbott Realtime SARS-CoV-2[10] Abbott Molecular
24 April 2020 PerkinElmer SARS-CoV-2 Real-time RT-PCR Assay[10] SYM-BIO LiveScience

As of 7 April 2020, the WHO had accepted two diagnostic tests under the Emergency Use Listing procedure (EUL) for use during the COVID‑19 pandemic.[11] Both in vitro diagnostics, the tests are genesig Real-Time PCR Coronavirus (COVID‑19) created by Primerdesign, and cobas SARS-CoV-2 Qualitative assay for use on the cobas® 6800/8800 Systems by Roche Molecular Systems. Approval means that these tests can also be given away by the United Nations.

How accurate is this?[change | change source]

In March 2020 China[12] reported problems with accuracy in their test kits.

In the United States, the test kits developed by the CDC had "flaws".[13]

80% of test kits the Czech Republic purchased from China gave wrong results.[14][15]

Inventions[change | change source]

A group of scientists from Hokkaido University developed an antibody test that could detect avian flu antibodies in only 20 minutes. They said their test could be changed to detect SARS-CoV-2.[16][17]

References[change | change source]

  1. Abbasi, Jennifer (17 April 2020). "The Promise and Peril of Antibody Testing for COVID-19". JAMA. 323 (19). JAMA Network: 1881–1883. doi:10.1001/jama.2020.6170. PMID 32301958. Retrieved 20 April 2020.
  2. Ioannidis, John P.A. (17 March 2020). "A fiasco in the making? As the coronavirus pandemic takes hold, we are making decisions without reliable data". STAT. Retrieved 22 March 2020.
  3. Symptom-Based Strategy to Discontinue Isolation for Persons with COVID-19 (2020) referenced
  4. Symptom-Based Strategy to Discontinue Isolation for Persons with COVID-19 (2020) referenced
    • CDC unpublished data
    • Wölfel et al. (2020)
    • Arons, Melissa M.; Hatfield, Kelly M.; Reddy, Sujan C.; Kimball, Anne; James, Allison; Jacobs, Jesica R.; Taylor, Joanne; Spicer, Kevin; Bardossy, Ana C.; Oakley, Lisa P.; Tanwar, Sukarma; Dyal, Jonathan W.; Harney, Josh; Chisty, Zeshan; Bell, Jeneita M.; Methner, Mark; Paul, Prabasaj; Carlson, Christina M.; McLaughlin, Heather P.; Thornburg, Natalie; Tong, Suxiang; Tamin, Azaibi; Tao, Ying; Uehara, Anna; Harcourt, Jennifer; Clark, Shauna; Brostrom-Smith, Claire; Page, Libby C.; Kay, Meagan; Lewis, James; Montgomery, Patty; Stone, Nimalie D.; Clark, Thomas A.; Honein, Margaret A.; Duchin, Jeffrey S.; Jernigan, John A. (2020). "Presymptomatic SARS-CoV-2 Infections and Transmission in a Skilled Nursing Facility". New England Journal of Medicine. 382 (22): 2081–2090. doi:10.1056/NEJMoa2008457. ISSN 0028-4793. PMC 7200056. PMID 32329971.
  5. Symptom-Based Strategy to Discontinue Isolation for Persons with COVID-19 (2020) referenced Wölfel et al. (2020)
  6. "Symptom-Based Strategy to Discontinue Isolation for Persons with COVID-19". CDC. 3 May 2020. Archived from the original on 4 May 2020.
  7. Symptom-Based Strategy to Discontinue Isolation for Persons with COVID-19 (2020) referenced
  8. Symptom-Based Strategy to Discontinue Isolation for Persons with COVID-19 (2020) referenced
  9. Symptom-Based Strategy to Discontinue Isolation for Persons with COVID-19 (2020) referenced
  10. 10.0 10.1 "WHO Emergency Use Listing for SARS-CoV-2 in vitro diagnostic products" (PDF). World Health Organization. Retrieved 4 May 2020.
  11. "WHO lists two COVID-19 tests for emergency use". World Health Organization. Retrieved 10 April 2020.
  12. Heartbreak in the Streets of Wuhan
  13. "State figures on testing raise questions about efforts to contain outbreak". The flaws with the testing kits first distributed by the federal government and bureaucratic hurdles that held up testing by private labs at hospitals, universities and testing chains
  14. Morning, Prague (26 March 2020). "80% of Rapid COVID-19 Tests the Czech Republic Bought From China are Wrong".
  15. VOJTĚCH BLAŽEK (23 March 2020). "Úřad dopředu psal, kdy mohou rychlotesty selhat. I tak je stát nasadil". Zeznam Zprávy (in Czech). Retrieved 7 April 2020. Indeed, the rapid tests that arrived from China a few days ago do not really reliably detect the infection at an early stage
  16. Hokkaido University (May 21, 2020). "New technology can detect anti-virus antibody in 20 minutes" (Press release). Retrieved May 26, 2020.
  17. Keine Nishiyama; Yohei Takeda; Masatoshi Maeki; Akihiko Ishida; Hirofumi Tani; Koji Shigemura; Akihide Hibara; Yutaka Yonezawa; Kunitoshi Imai; Haruko Ogawa; Manabu Tokeshi (August 1, 2020). "Rapid detection of anti-H5 avian influenza virus antibody by fluorescence polarization immunoassay using a portable fluorescence polarization analyzer". Sensors and Actuators B: Chemical. 316: 128160. doi:10.1016/j.snb.2020.128160. PMC 7172727. PMID 32322135.