Antibody Testing Information

Posted on April 21, 2020 | Posted by

Antibody testing– in order to let you make an intelligent decision of whether or not you want to get antibody testing, I would like to first explained the value of antibody testing
  • Antibody testing measures whether your immune system has developed the ability to fight COVID 19. If you have mounted an antibody response, it means you have been exposed and should be able to defend yourself from COVID 19 when re-exposed and not get sick. It is very important to understand that we do not know how long this immunity lasts. In viruses like chickenpox and measles, it might last a lifetime. With some viruses immunity only lasts a few weeks.
  • If testing is positive showing the presence of antibodies theoretically you should be safe to others. Until we know more in the next few weeks, everyone should still proceed with caution, especially around high risk individuals.
  • With most of the point of service tests available, the false-negative and false positive rates are both about 10%. This means that about 10% of people who test positive are actually NOT immune. Likewise, about 10% of people who test negative actually have antibodies.
Community testing- this is the most valuable use of antibody testing. This is what was recently done in Santa Clara California by Stanford University and Chelsea Massachusetts by Mass General Hospital. They randomly tested people and found out that 30% of people in Chelsea Massachusetts, were immune to COVID 19, many of whom never had symptoms. The Stanford study suggested that the death rate may only be 1 in 1000, much lower than originally thought and lower than that for influenza. This is encouraging early information, and the more we have community antibody testing like this, the more refined we can intelligently make recommendations about opening up our nation. In this widespread testing a 10% false negative/positive rate does not affect the numbers significantly.
Individual testing– In a single test, the 10% error rate is very significant. Think of the devastation it could cause should a person test positive, suggesting they are immune, but really are not. Therefore, if you choose to get antibody testing, still proceed with caution around high risk individuals. Some additional thoughts to consider:
  • In someone like me who tested positive with the COVID antigen nasal swab, or someone who had symptoms highly suspicious for COVID 19, a positive test is very believable, more than in someone who had no symptoms. I would actually question a negative test, because there is a high likelihood it could be a false negative. Someone who had symptoms but did not get nasal swab testing is the best candidate.
  • In someone who has been exposed, but did not have significant symptoms, or in someone else who had marginal symptoms, a positive test is reassuring, but not definitive. You should still proceed with caution, especially if you are high risk.
  • If someone had no symptoms or known exposure, a negative test is quite believable. A positive test is reassuring, but more suspect. You are the group who is most likely to have a false positive. Again, be very cautious if you are high risk. To that point, I am not sure the antibody test is worthwhile in a high-risk person who has had no symptoms or exposure.
Testing coming to RHS:
  • As of today, our supplier Henry Schein does not have office-based antibody testing for us to purchase yet, but they say it should be available “soon”. I have been given the name of another supplier and am hoping I can purchase it from them.
  • I do not know the exact price, but anticipate it being about $45-$50.
  • We can give you a receipt if you would like to submit to insurance.
  • I plan to make this available to you and family members if you would like.
  • As a public service I will make it available to our newsletter subscriber’s too.
  • I plan to order as soon they are available, but would like to get an idea of how many tests to order. Please reply to office@RHSLiveWell.com with how many tests you would like us to reserve for you. We will notify you when it is available.