Skip to content
  • About
  • Contact
  • Contribute
  • Book
  • Careers
  • Podcast
  • Recommended
  • Speaking
  • All
  • Physician
  • Practice
  • Policy
  • Finance
  • Conditions
  • .edu
  • Patient
  • Meds
  • Tech
  • Social
  • Video
    • All
    • Physician
    • Practice
    • Policy
    • Finance
    • Conditions
    • .edu
    • Patient
    • Meds
    • Tech
    • Social
    • Video
    • About
    • Contact
    • Contribute
    • Book
    • Careers
    • Podcast
    • Recommended
    • Speaking

4 things people should know about COVID-19 antibody testing

Christine Lau, MD
Conditions
June 18, 2020
Share
Tweet
Share

1. Not all antibody tests are the same.

There are currently over a hundred different antibody tests – in different phases of development. Only a small subset of these tests has FDA approval for diagnostic purposes and emergency use authorization. A majority of these tests are approved for research and surveillance purposes only (some pending FDA approval). Many are still in development and are not FDA approved yet.

Some of these tests involve only a fingerprick and yield results in 10 to 20 minutes. Others, which use whole blood, plasma, or serum samples, require more sophisticated laboratory equipment and can take several hours to yield results.

2. Not all antibody tests have the same accuracy.

These tests all have differing sensitivities (true positive rate) and specificities (true negative rate). Since these tests are new, and this virus is new, these tests were validated on only a few hundred samples. Rates of sensitivity and specificity are continuously changing as time passes, and more data is gathered.

3. The antibody test is different from the nasopharyngeal or oropharyngeal swab.

Antibody testing identifies exposure to SARS-CoV-2 (the virus which causes COVID-19) by looking for antibodies generated by the immune response. Most SARS-CoV-2 antibody tests detect IgM and/or IgG. IgM is the first antibody the body builds when fighting a new infection and may indicate you are still infected or recently recovered. IgG, on the other hand, take 7 to 10 days to develop, and indicate you have previously been infected and recovered.

The PCR tests with the nasopharyngeal or oropharyngeal swab detect the presence of viral material during an active infection. The PCR tests, therefore, diagnose active infection but does not indicate if a person has been infected in the past and recovered.

4. Testing positive for IgG does not guarantee immunity and mean a “free pass.” You still have to be careful.

Even if you test positive for IgG, which indicates you have contracted and recovered from the virus, the data is of limited use. This coronavirus is new, and no one knows how long these IgG antibodies last for. There is a possibility of the virus mutating and, therefore, a risk of reinfection. Furthermore, you can still carry the virus and spread it to others. It is still important to follow safety precautions, including wearing a mask and social distancing.

Christine Lau is a physician.

Image credit: Shutterstock.com

Prev

Pediatric emergency care during a time of strict social isolation

June 18, 2020 Kevin 0
…
Next

Dissecting systemic racism in health care

June 18, 2020 Kevin 6
…

ADVERTISEMENT

Tagged as: COVID, Infectious Disease

Post navigation

< Previous Post
Pediatric emergency care during a time of strict social isolation
Next Post >
Dissecting systemic racism in health care

ADVERTISEMENT

More by Christine Lau, MD

  • 4 lessons the pandemic has taught health care

    Christine Lau, MD
  • 6 things people should know about the COVID-19 vaccines

    Christine Lau, MD
  • Be grateful this holiday season

    Christine Lau, MD

Related Posts

  • How to get patients vaccinated against COVID-19 [PODCAST]

    The Podcast by KevinMD
  • COVID-19 divides and conquers

    Michele Luckenbaugh
  • State sanctioned executions in the age of COVID-19

    Kasey Johnson, DO
  • A patient’s COVID-19 reflections

    Michele Luckenbaugh
  • Starting medical school in the midst of COVID-19

    Horacio Romero Castillo
  • COVID-19 shows why we need health insurance

    Jingyi Liu, MD

More in Conditions

  • When recurrent UTIs might actually be bladder cancer

    Fara Bellows, MD
  • How chronic stress harms the heart in minority communities

    Monzur Morshed, MD and Kaysan Morshed
  • Could antibiotics beat heart disease where statins failed?

    Larry Kaskel, MD
  • Universities must tap endowments to sustain biomedical research

    Adeel Khan, MD
  • Apprenticeship reshapes medical training for confident clinicians

    Claude E. Lett III, PA-C
  • Why palliative care is more than just end-of-life support

    Dr. Vishal Parackal
  • Most Popular

  • Past Week

    • Why palliative care is more than just end-of-life support

      Dr. Vishal Parackal | Conditions
    • When life makes you depend on Depends

      Francisco M. Torres, MD | Physician
    • Guilty until proven innocent? My experience with a state medical board.

      Jeffrey Hatef, Jr., MD | Physician
    • Why medical notes have become billing scripts instead of patient stories

      Sriman Swarup, MD, MBA | Tech
    • How denial of hypertension endangers lives and what doctors can do

      Dr. Aminat O. Akintola | Conditions
    • A powerful story of addiction, strength, and redemption

      Ryan McCarthy, MD | Physician
  • Past 6 Months

    • Why transgender health care needs urgent reform and inclusive practices

      Angela Rodriguez, MD | Conditions
    • COVID-19 was real: a doctor’s frontline account

      Randall S. Fong, MD | Conditions
    • Why primary care doctors are drowning in debt despite saving lives

      John Wei, MD | Physician
    • New student loan caps could shut low-income students out of medicine

      Tom Phan, MD | Physician
    • Confessions of a lipidologist in recovery: the infection we’ve ignored for 40 years

      Larry Kaskel, MD | Conditions
    • mRNA post vaccination syndrome: Is it real?

      Harry Oken, MD | Conditions
  • Recent Posts

    • When recurrent UTIs might actually be bladder cancer

      Fara Bellows, MD | Conditions
    • How restrictive opioid policies worsen the crisis

      Kayvan Haddadan, MD | Physician
    • Why doctors should rethink investing compared to the average U.S. investor [PODCAST]

      The Podcast by KevinMD | Podcast
    • How chronic stress harms the heart in minority communities

      Monzur Morshed, MD and Kaysan Morshed | Conditions
    • Could antibiotics beat heart disease where statins failed?

      Larry Kaskel, MD | Conditions
    • The dying man who gave me flowers changed how I see care

      Augusta Uwah, MD | Physician

Subscribe to KevinMD and never miss a story!

Get free updates delivered free to your inbox.


Find jobs at
Careers by KevinMD.com

Search thousands of physician, PA, NP, and CRNA jobs now.

Learn more

View 1 Comments >

Founded in 2004 by Kevin Pho, MD, KevinMD.com is the web’s leading platform where physicians, advanced practitioners, nurses, medical students, and patients share their insight and tell their stories.

Social

  • Like on Facebook
  • Follow on Twitter
  • Connect on Linkedin
  • Subscribe on Youtube
  • Instagram

ADVERTISEMENT

ADVERTISEMENT

  • Most Popular

  • Past Week

    • Why palliative care is more than just end-of-life support

      Dr. Vishal Parackal | Conditions
    • When life makes you depend on Depends

      Francisco M. Torres, MD | Physician
    • Guilty until proven innocent? My experience with a state medical board.

      Jeffrey Hatef, Jr., MD | Physician
    • Why medical notes have become billing scripts instead of patient stories

      Sriman Swarup, MD, MBA | Tech
    • How denial of hypertension endangers lives and what doctors can do

      Dr. Aminat O. Akintola | Conditions
    • A powerful story of addiction, strength, and redemption

      Ryan McCarthy, MD | Physician
  • Past 6 Months

    • Why transgender health care needs urgent reform and inclusive practices

      Angela Rodriguez, MD | Conditions
    • COVID-19 was real: a doctor’s frontline account

      Randall S. Fong, MD | Conditions
    • Why primary care doctors are drowning in debt despite saving lives

      John Wei, MD | Physician
    • New student loan caps could shut low-income students out of medicine

      Tom Phan, MD | Physician
    • Confessions of a lipidologist in recovery: the infection we’ve ignored for 40 years

      Larry Kaskel, MD | Conditions
    • mRNA post vaccination syndrome: Is it real?

      Harry Oken, MD | Conditions
  • Recent Posts

    • When recurrent UTIs might actually be bladder cancer

      Fara Bellows, MD | Conditions
    • How restrictive opioid policies worsen the crisis

      Kayvan Haddadan, MD | Physician
    • Why doctors should rethink investing compared to the average U.S. investor [PODCAST]

      The Podcast by KevinMD | Podcast
    • How chronic stress harms the heart in minority communities

      Monzur Morshed, MD and Kaysan Morshed | Conditions
    • Could antibiotics beat heart disease where statins failed?

      Larry Kaskel, MD | Conditions
    • The dying man who gave me flowers changed how I see care

      Augusta Uwah, MD | Physician

MedPage Today Professional

An Everyday Health Property Medpage Today
  • Terms of Use | Disclaimer
  • Privacy Policy
  • DMCA Policy
All Content © KevinMD, LLC
Site by Outthink Group

4 things people should know about COVID-19 antibody testing
1 comments

Comments are moderated before they are published. Please read the comment policy.

Loading Comments...