How are they different from PCR tests used for the primary diagnosis of COVID-19?

The COVID-19 antibody test is a throw in of serology test, or blood test.

This immune response test detects the immune proteinscalled antibodiesthat the body produces in response to the virus.

It does not detect the virus itself.

What Is an Antibody?

The antibody “recognizes” the invader by proteins on its surface calledantigens.

COVID-19 antibody tests are looking for the antibodies made in response to exposure to the SARS-CoV-2 virus.

How the Tests Work

There are two different technologies used for COVID-19 antibody test.

While LFA-based finger-stick tests are faster and more convenient, ELISA-based tests tend to be more accurate.

It is only used after the body has produced enough antibodies to reach detectable levels.

For IgG antibodies, this usually takes 11 to 18 days from exposure.

For IgM antibodies, detection may be achieved by as early as four to five days after exposure.

If you test too early, you may get afalse-negativeresult.

A false-negative means that you have been infected even if the test says otherwise.

The window of opportunity for COVID-19 antibody testing is unknown.

Part of the reason for the large-scale antibody surveillance is to find out.

Individual Testing

From an individual standpoint, a COVID-19 antibody test may be less useful.

Thetransfusionof defensive antibodiesmayhelp severely ill people better fight and recover from a COVID-19 infection.More research is needed.

Others have since been authorized.

Other unscrupulous online resellers have taken to shipping fake tests directly to consumers.

Never buy a COVID-19 antibody test online.

There are no such tests approved for home use.

How Accurate Are the Tests?

The lower the specificity of a test, the greater the risk of a false-positive result.

False-negatives are more common with COVID-19 antibody tests, due in part to the variable sensitivities of the tests.

False-positive results are uncommon but can occur.

It is important to remember that the sensitivity and specificity of the authorized tests are estimates only.

In a real-world setting, the tests often fall short.

The blood draw may cause temporary discomfort for some people, but it is usually not painful.

The process is something most people are familiar with.

Call your doctor if there is increased redness or pain, swelling, fever, or visible discharge.

Infection is rare but may occur.

ELISA tests are fully automated and can usually be completed in the lab within 90 minutes.

Fasting is not required for the COVID-19 antibody test.

In such cases, the test should be repeated.

These services are almost always paid upfront and restricted to adults 18 and over.

People under 18 can only obtain testing under the instructions of a doctor.

Quest Diagnostics

LapCorp

The Quest and LabCorp antibody tests are not available in all states.

People who earn more than the prescribed annual income may not be covered.

Getting tested without a doctor’s approval may end up costing you money.

Participating in community-based surveillance studies will most definitely aid in the cause.

Testing positive does not alter the way in which the disease is treated or prevented.

For the most recent updates on COVID-19, visit ourcoronavirus news page.

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