Quantcast
ZME Science
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
    Menu
    Natural Sciences
    Health
    History & Humanities
    Space & Astronomy
    Technology
    Culture
    Resources
    Natural Sciences

    Physics

    • Matter and Energy
    • Quantum Mechanics
    • Thermodynamics

    Chemistry

    • Periodic Table
    • Applied Chemistry
    • Materials
    • Physical Chemistry

    Biology

    • Anatomy
    • Biochemistry
    • Ecology
    • Genetics
    • Microbiology
    • Plants and Fungi

    Geology and Paleontology

    • Planet Earth
    • Earth Dynamics
    • Rocks and Minerals
    • Volcanoes
    • Dinosaurs
    • Fossils

    Animals

    • Mammals
    • Birds
    • Fish
    • Reptiles
    • Amphibians
    • Invertebrates
    • Pets
    • Conservation
    • Animals Facts

    Climate and Weather

    • Climate Change
    • Weather and Atmosphere

    Geography

    Mathematics

    Health
    • Drugs
    • Diseases and Conditions
    • Human Body
    • Mind and Brain
    • Food and Nutrition
    • Wellness
    History & Humanities
    • Anthropology
    • Archaeology
    • Economics
    • History
    • People
    • Sociology
    Space & Astronomy
    • The Solar System
    • The Sun
    • The Moon
    • Planets
    • Asteroids, Meteors and Comets
    • Astronomy
    • Astrophysics
    • Cosmology
    • Exoplanets and Alien Life
    • Spaceflight and Exploration
    Technology
    • Computer Science & IT
    • Engineering
    • Inventions
    • Sustainability
    • Renewable Energy
    • Green Living
    Culture
    • Culture and Society
    • Bizarre Stories
    • Lifestyle
    • Art and Music
    • Gaming
    • Books
    • Movies and Shows
    Resources
    • How To
    • Science Careers
    • Metascience
    • Fringe Science
    • Science Experiments
    • School and Study
    • Natural Sciences
    • Health
    • History and Humanities
    • Space & Astronomy
    • Culture
    • Technology
    • Resources
  • Reviews
  • More
    • Agriculture
    • Anthropology
    • Biology
    • Chemistry
    • Electronics
    • Geology
    • History
    • Mathematics
    • Nanotechnology
    • Economics
    • Paleontology
    • Physics
    • Psychology
    • Robotics
  • About Us
    • About
    • The Team
    • Advertise
    • Contribute
    • Privacy Policy
    • Contact
No Result
View All Result
ZME Science

No Result
View All Result
ZME Science

Home → Features → Health → Diseases and Conditions

How does a coronavirus test work

Early testing is crucial to curbing the spread of any infectious disease.

Tibi Puiu by Tibi Puiu
May 6, 2023
in Diseases and Conditions

If you live close to an area where COVID-19 cases have been reported or if you have experienced symptoms such as fever, shortness of breath, or cough, you might suspect you are infected. This might be a good time to get tested — but how does a coronavirus test work?

Credit: Pixabay.

You can’t perform a coronavirus test yourself. First, a doctor or health worker will swab the back of your throat with a sterile Q-tip in order to collect a sample of the secretions being produced there.

The throat swab is then run through polymerase chain reaction (PCR) testing that amplifies selected sections of DNA or RNA, replicating them millions of times until they are large enough to be detected by a special lab instrument. This highly efficient method enables scientists to identify infectious agents or highlight genes in ancient genomes even when working with minute quantities of DNA or RNA.

The story of how PCR got invented is actually quite inspiring. Kary Mullis, the scientist who first performed it, got the idea in 1983 while he was driving his motorcycle one night down the Pacific Coast Highway 128. Mullis — who at the time was employed for a large biotech company charged with making short chains of DNA for other researchers –was toying in his mind with new ways of analyzing mutations in DNA when he realized that amplifying any DNA region was possible. In 1993, he shared the Nobel Prize in chemistry with Michael Smith.

Today, PCR is a cornerstone technology used by scientists working in the lab or at biotech giants like Stilla Technologies to diagnose genetic diseases, do DNA fingerprinting, identify bacteria and viruses, study human evolution, clone the DNA of an Egyptian mummy, establish paternity or biological relationships, and much more.

When identifying a viral infection — such as the new coronavirus, known as SARS-CoV-2, that causes COVID-19 — PCR tests look for specific genetic material that is unique to the virus’ genome.

At the lab, the nucleic acid is extracted from your sample and amplified to produce a larger sample.

SARS-CoV-2’s genome is made of 30,000 nucleotides — the building blocks of DNA and RNA. However, not all nucleotide sequences are critical for diagnosis. PCR tests developed at the University of Washington, for instance, look for just 100 nucleotides that are specific to SARS-CoV-2, including two genes that are specific to the novel coronavirus.

If both genes are detected the test is positive; a single gene means the test is inconclusive; while the absence of both genes renders a negative test result.

There are also serological tests that look for antibodies produced by the body to fight off the virus. Instead of sampling the back of the throat, a health worker will draw a blood sample for this kind of test.

Antibody tests for COVID-19 have already been developed in Singapore and China.

The advantage of a serological test over a PCR test is that COVID-19-specific antibodies are still present in a person’s blood even after recovery. This way, doctors can diagnose recovered cases even when a person was not aware they were infected with SARS-CoV-2. Most cases of COVID-19 are mild, so many people might get infected with the virus and then get well, thinking they merely had the flu or some respiratory illness. In fact, many cases of COVID-19 are asymptomatic. A PCR test, on the other hand, can only detect the presence of the virus if the patient is currently sick.

Both kinds of tests can fail, however, if they’re administered in the very early phase of infection. The viral load may be too low for PCR to detect SARS-CoV-2 genes or the body may not have had enough time to produce antibodies against the virus.

Testing is crucial to curbing epidemics

PCR and antibody tests take just a few hours to run and a complete diagnosis can be provided within 24-72 hours.

While there is currently no vaccine or specific treatment for COVID-19, that doesn’t mean testing is pointless. In fact, early testing is crucial to curbing the spread of infection responsible for COVID-19. When a person is diagnosed with a contagious disease, they can be placed under quarantine, thus avoiding infecting other people.

South Korea now has more people leaving hospitals after recovery than they have new cases — but only after they imposed drastic containment measures and performed over 240,000 tests. Elsewhere, the U.S. is woefully lagging behind, having performed a little more than 7,000 Covid-19 tests as of March 11.

Updated to reflect #coronavirus testing capacity in hospital and clinical laboratories pic.twitter.com/WriCUMiyqS

— COVID-19 Test Capacity (@COVID2019tests) March 11, 2020
Was this helpful?
Thanks for your feedback!
Related posts:
  1. Finger-prick test can diagnose Ebola as easily as a pregnancy test
  2. The “step test”: If you can complete this simple 60-second test, it means you’re heart is in good shape
  3. CRISPR coronavirus test can diagnose COVID-19 in 40 minutes rather than hours
  4. Slovakia wants to test its entire population for coronavirus, but the project is challenging
  5. How many slaves work for you? Find out in this online test
Tags: coronavirusCOVID-19

ADVERTISEMENT
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
  • Reviews
  • More
  • About Us

© 2007-2021 ZME Science - Not exactly rocket science. All Rights Reserved.

No Result
View All Result
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
    • Natural Sciences
    • Health
    • History and Humanities
    • Space & Astronomy
    • Culture
    • Technology
    • Resources
  • Reviews
  • More
    • Agriculture
    • Anthropology
    • Biology
    • Chemistry
    • Electronics
    • Geology
    • History
    • Mathematics
    • Nanotechnology
    • Economics
    • Paleontology
    • Physics
    • Psychology
    • Robotics
  • About Us
    • About
    • The Team
    • Advertise
    • Contribute
    • Privacy Policy
    • Contact

© 2007-2021 ZME Science - Not exactly rocket science. All Rights Reserved.

Don’t you want to get smarter every day?

YES, sign me up!

Over 35,000 subscribers can’t be wrong. Don’t worry, we never spam. By signing up you agree to our privacy policy.

✕
ZME Science News

FREE
VIEW