Current summary (July 8, 2020):

  • Testing is available for current infection (antigen testing) and past infection (antibody testing)
  • NEITHER test is very accurate, and we don’t really know how accurate they are. Accuracy also depends on who makes the test, and there are a lot of tests out there, all of which have emergency approval only and have not been proven accurate. Antibody tests may be even less accurate than antigen tests.
  • We have no idea what a positive antibody test really means. We have no idea if antibodies mean that a person is immune or partially immune or may catch it again and again. We also have no idea if there is indeed some protection, how long it lasts. A month? Six months? A year? Ten years? A lifetime? For other coronaviruses, immunity does not last very long. No one should think they are safe because they have a positive antibody test.
  • Testing is not currently recommended for children who are not sick enough to be admitted to the hospital.

Types of tests

There are two types of tests available for covid-19, one to find out if you are currently infected, and one to tell if you have ever had it.

  • Viral testing is a test for current infection. It tests for the presence of the virus in nasal mucous, either by genetic material (molecular test) or viral antigens. There are many brands out there, and some are much more reliable than others. Most have many false positive and/or false negative results. Viral antigen tests are faster but not as reliable as molecular tests. If a viral antigen test is positive, is is very likely to be true; however, if it is negative, it may not be accurate and you might actually be infected.
  • Antibody testing is a blood test for immune system antibodies to the virus. It means that a person has been infected in the past. It becomes positive 1-3 weeks after infection. No one knows if having antibodies provides any protection at all, and if it does, no one knows how long it lasts. For other coronaviruses, we do not tend to develop strong immunity. This may also make it difficult to develop an effective vaccine.

Who should be tested?

Testing is not always necessary. While widespread testing may be part of an answer to getting the epidemic under control, testing is spotty and the tests are not always accurate. It may become even more important to limit testing as shortages of tests occur. (This is starting to happen).

Antibody testing for past infection

Antibody testing is not recommended for most children or adults (despite medical practices in our community advertising them). They are useful for public health tracking and for people with prolonged illness that might be related to coronavirus infection, including the systemic inflammatory syndromes. However, as noted above, no one knows what a positive antibody test actually means, other than having been infected. It does NOT mean that a person is immune to catching it again.

Testing for current infection

For children, most experts feel that viral testing is not usually necessary unless the child is seriously ill, usually ill enough to be admitted to the hospital.Children with fever, cough, and other respiratory symptoms should stay home until well anyway. Testing will not change treatment of the child. Testing might help contact tracing, or family members who may have been exposed. However, one problem with testing children is that many children with the virus will have a negative test (depending on the test that is done), so it is best to keep them away from others as long as they are sick.

In general, viral testing is recommended for:

High priority testing

  • hospitalized patients
  • healthcare workers and first responders
  • people living in close quarters (living facilities, nursing homes)

It is also recommended for:

  • patients who are ill and are suspected of having covid-19
  • people without symptom who are close contacts of a person with covid-19
  • people in high-risk settings even if there is not exposure, depending on local conditions and recommendations
  • as a strategy to see if infection has resolved
  • public health surveillance/research

See CDC Testing Recommendations (written for healthcare professionals)

There is an online resource and app developed by Apple and the CDC to help you determine if you need testing.

Where to get tested

See our Where to Get Testing page for current information.

Resources