Accurate and timely testing is vitally important when trying to stop the outbreak of an infectious disease such as COVID-19, which is caused by the new coronavirus (SARS-CoV-2).
How do we test for the new coronavirus?
The World Health Organization (WHO) recommends that people suspected of having COVID-19 be screened for the new coronavirus with tests such as RT-PCR (reverse transcription polymerase chain reaction). RT-PCR is a type of laboratory test that can be used to detect small amounts of the new coronavirus in a sample taken from a patient.
The testing process is pretty straightforward and begins with a healthcare professional swabbing a patient's throat or nose for mucus. The sample is then sent to a lab, where it's first mixed with substances called reagents in a test tube. It’s then put into a thermocycler machine and duplicate copies of the genetic material in the sample are made. If the sample contains the new coronavirus, then its presence will be amplified or increased confirming a positive result and diagnosis of COVID-19.
Can I test myself at home?
On March 9, 2020 a home-based COVID-19 sampling service was reported to be available in Malaysia. Home-testing kits are also expected to be available in the Seattle, US, area soon under a project funded by Bill Gates and his foundation. Results from the home-testing kits are expected to take 1-2 days in the US and local health officials will be notified of positive results. An online form will be available for those with COVID-19 to complete to help health officials identify others who may have the disease.
What problems have there been with testing?
There have been a number of problems with testing for the new coronavirus. Here’s a quick look at 5 of the issues.
1. Negative results despite the patient having COVID-19
COVID-19 is a lung disease, so it’s possible that even if a person has the disease a swab of their throat or nose might not contain enough of the virus to produce a positive result. False negatives are also possible if the sample takes too long to get to the laboratory to be tested, or isn’t transported under appropriate conditions. Freezing of samples is recommended if they are likely to take a while to get to the lab (-20ºC [-4ºF] or ideally -70ºC [-94ºF]), otherwise it’s possible to ship and store them at 2-8ºC (35.6-46.4ºF) if they won't spend long in transit.
2. Faulty test kits
Despite the WHO making a test kit available, the US declined to use it and decided to make its own. Unfortunately, its initial efforts contained a faulty reagent, meaning that the tests provided inconclusive results. However, on February 28, 2020, the US Centers for Disease Control and Prevention (CDC) confirmed that new test kits were available for order that did not include the faulty reagent.
3. Testing not available to everyone
During the initial stages of the COVID-19 outbreak, many countries only provided testing to people who had traveled from China or who were in contact with someone who had. Such rules, however, appear to have delayed the diagnosis of some cases of the disease. For example, the first case of community spread of COVID-19 in the US is thought to have been initially denied testing. Although Dr Nancy Messonnier at the CDC has stated that the first call they had about the patient was on Sunday, February 23, 2020, UC Davis Health has reported that their earlier requests to have the patient tested were turned down. Others have also reported being turned down for testing.
Fortunately, the first patients diagnosed with COVID-19 in England were tested despite not meeting the testing criteria. Had the testing criteria been strictly applied in the UK, then those cases might have been missed allowing greater spread of the virus.
4. Lack of testing kits
On March 6, 2020, US President Donald Trump announced that “anybody who wants a test gets a test”. However, just the day before the Vice President stated that “we don’t have enough tests today to meet what we anticipate will be the demand going forward”.
Expensive medical bills are likely to be a deterrent to testing, according to some experts in the US. While Federal funds cover the cost of the COVID-19 test at federal, state and local public health laboratories, they do not cover testing costs at academic or commercial labs. They also don’t cover the cost of other tests or treatment. While reports of a US man being charged more than $US3000 for a test have been found to be incorrect, his insurance was billed for an emergency room visit and testing for a number of upper respiratory pathogens. The man wasn't tested for COVID-19, but was eventually diagnosed with the flu. The costs associated with getting that diagnosis highlight how unaffordable seeking treatment is likely to be for many of the more than 27 million Americans without health insurance.
What is being done to overcome the problems with testing?
- Researchers in China have looked into additional ways of diagnosing COVID-19. They have found that chest CT should be considered as a screening tool in epidemic areas because of the tests high sensitivity for COVID-19.
- The number of testing sites is being increased. For example, while initial testing was only available in the US via the CDC, testing is now available at 78 state and local public health labs. Private labs, including Lab Corp. and Quest Diagnostics are also providing testing.
- Some insurance companies in the US have announced that they won’t charge for coronavirus testing and others have been ordered not too. The Mayor of New York has also announced that testing will be available to everyone in the city, regardless of their ability to pay or immigration status.
- World Health Organization (WHO). Laboratory testing for 2019 novel coronavirus (2019-nCoV) in suspected human cases. March 2, 2020. Available at: https://www.who.int/publications-detail/laboratory-testing-for-2019-novel-coronavirus-in-suspected-human-cases-20200117. [Accessed March 9, 2020].
- Wall Street Journal. February 26, 2020. How Coronavirus Test Kits Work. Retrieved from: https://www.youtube.com/watch?v=tgyzdgf66eM. [Accessed March 9, 2020].
- Scitable by Nature Education. Scientists Can Make Copies of a Gene through PCR. Available at: https://www.nature.com/scitable/topicpage/scientists-can-make-copies-of-a-gene-6525968/. [Accessed March 9, 2020].
- Science Direct. Reverse Transcription Polymerase Chain Reaction. Available at: https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/reverse-transcription-polymerase-chain-reaction. [Accessed March 9, 2020].
- New Straits Times. Test for Covid-19 from your home. March 9, 2020. Available at: https://www.nst.com.my/news/nation/2020/03/573213/test-covid-19-your-home. [Accessed March 10, 2020].
- The Seattle Times. Gates-funded program will soon offer home-testing kits for new coronavirus. March 8, 2020. Available at: https://www.seattletimes.com/seattle-news/health/gates-funded-program-will-soon-offer-home-testing-kits-for-new-coronavirus/. [Accessed March 9, 2020].
- UC Davis Health. Novel Coronavirus Patient and Precautions at UC Davis Medical Center. February 26, 2020. Available at: https://health.ucdavis.edu/health-news/contenthub/novel-coronavirus-patient-and-precautions-at-uc-davis-medical-center/2020/02. [Accessed March 9, 2020].
- Centers for Disease Control and Prevention (CDC). Transcript for the CDC Telebriefing Update on COVID-19. February 28, 2020 Available at: https://www.cdc.gov/media/releases/2020/t0228-COVID-19-update.html. [Accessed March 9, 2020].
- Allison Burnett (March 8, 2020) My friend is a respiratory nurse in a US urban hospital. A woman, recently returned from Italy, came in with all the symptoms of #COVID19. In order to test her, the doctors needed approval from the government. The Feds turned down their request. She was sent home [Twitter POST]. Retrieved from: https://twitter.com/Allison_Burnett/status/1236476132272168960
- The Lancet. Lessons for managing high-consequence infections from first COVID-19 cases in the UK. February 27, 2020. DOI: https://doi.org/10.1016/S0140-6736(20)30463-3. [Accessed March 9, 2020].
- Centers for Disease Control and Prevention (CDC). Coronavirus Disease 2019 (COVID-19). Testing. Available at: https://www.cdc.gov/coronavirus/2019-ncov/about/testing.html. [Accessed March 9, 2020].
- Politico. How testing failures allowed coronavirus to sweep the U.S. March 6, 2020. Available at: https://www.politico.com/news/2020/03/06/coronavirus-testing-failure-123166. [Accessed March 9, 2020].
- Science. The United States badly bungled coronavirus testing—but things may soon improve. February 28, 2020. Available at: https://www.sciencemag.org/news/2020/02/united-states-badly-bungled-coronavirus-testing-things-may-soon-improve. [Accessed March 9, 2020].
- Politico. Trump officials unsure how many people tested for coronavirus. March 7, 2020. Available at: https://www.politico.com/news/2020/03/07/coronavirus-testing-white-house-briefing-123411?covid_m. [Accessed March 9, 2020].
- CNBC. Trump says, ‘Anybody who wants a test gets a test’ after Pence says US can’t meet coronavirus testing demand. March 6, 2020. Available at: https://www.cnbc.com/2020/03/06/trump-anybody-who-wants-a-test-gets-a-test-amid-shortage-for-coronavirus.html. [Accessed March 9, 2020].
- USA Today. How much does a coronavirus test cost? Fact check of COVID-19 medical bills finds that online rumor of a $3,000 charge is false. March 5, 2020. Available at: https://www.usatoday.com/story/news/health/2020/03/05/fact-check-coronavirus-test-does-not-cost-3000-medical-bills/4949078002/. [Accessed March 9, 2020].
- KFF. Key Facts about the Uninsured Population. December 13, 2019. Available at: https://www.kff.org/uninsured/issue-brief/key-facts-about-the-uninsured-population/. [Accessed March 9, 2020].
- Radiology. Correlation of Chest CT and RT-PCR Testing in Coronavirus Disease 2019 (COVID-19) in China: A Report of 1014 Cases. February 26, 2020. Available at: https://doi.org/10.1148/radiol.2020200642. [Accessed March 9, 2020].
- Centers for Disease Control and Prevention (CDC). Coronavirus Disease 2019 (COVID-19). Testing in the U.S. Available at: https://www.cdc.gov/coronavirus/2019-ncov/testing-in-us.html. [Accessed March 9, 2020].
- CNBC. Private labs start testing for coronavirus, prompting concerns about cost and insurance co-pays. March 6, 2020. Available at: https://www.cnbc.com/2020/03/06/private-labs-start-testing-for-coronavirus-prompting-cost-concerns.html. [Accessed March 9, 2020].
- The Oregonian. Several Oregon insurance companies won’t charge for coronavirus testing, Gov. Kate Brown says. March 5, 2020. Available at: https://www.oregonlive.com/coronavirus/2020/03/several-oregon-insurance-companies-wont-charge-for-coronavirus-testing-gov-kate-brown-says.html?utm_source=twitter&utm_campaign=oregonian_sf&utm_medium=social. [Accessed March 9, 2020].
- San Francisco Chronicle. California orders insurers to waive out-of-pocket costs for coronavirus testing. March 5, 2020. Available at: https://www.sfchronicle.com/business/networth/article/California-orders-insurers-to-waive-out-of-pocket-15109214.php#?utm_campaign=CMS%20Sharing%20Tools%20(Premium)&utm_source=t.co&utm_medium=referral. [Accessed March 9, 2020].
- NYC Mayor's Office (March 8, 2020) If you think you have the symptoms of COVID-19, do not worry about the cost of testing or treatment. We will take care of you even if you have no insurance or cannot pay. Call 311 for assistance [Twitter POST]. Retrieved from: https://twitter.com/NYCMayorsOffice/status/1236370028955602950
- TC. Trying to make up for lost time, the CDC will distribute 1.1M COVID-19 tests by this weekend. March 7, 2020. Available at: https://techcrunch.com/2020/03/06/trying-to-make-up-for-lost-time-the-cdc-will-distribute-1-1-million-covid-19-tests-this-weekend/. [Accessed March 9, 2020].