Testing… Testing… Testing…

The news and social media is plagued with debate regarding whether or not we are testing appropriately. I can say with a fair amount of certainty, that we, as a country, are not testing nearly enough as we should be. Despite what the current administration is saying, we may have adequate testing capacity but not enough supply. This may seem confusing, but if you listen to the popular, and undisputedly trustworthy opinion of Dr. Anthony Fauci, we do not have enough testing…period. Yes it sounds great when Donald Trump and Mike Pence say we have more than enough testing capacity. What this actually means, is that we are able to process a large amount of tests, however, we are lacking the reagents, tubes, and swabs required to actually collect, transport, and use for testing. This is a BIG difference. If you know you can bake two dozen cookies without breaking a sweat, but you only have enough flour and sugar for one dozen cookies, you can only make one dozen. This is the same situation. We can process millions of tests per day now, but we don’t have the supplies to collect them. Unless we start testing more and more, we won’t know how widespread this disease really is, how to appropriately quarantine to stop the spread to others, as well as reopen the country back up.

So what kind of testing is available and how does it work?

The first form of testing at this time is what is called PCR RNA testing. This is the test you see and hear about (and maybe have even had already) in which a nurse or other healthcare provider will swab inside the nose or throat. This process involves collecting mucous in the nose and throat where the virus lives. It is then put into a reagent (chemical) in which the virus in the mucous on the swab is broken apart exposing its RNA (genetic information) that is held inside its core. Simply put, it is then placed into a machine which then makes thousands, if not millions, of copies of the COVID-19 RNA. If the virus was indeed in the person’s nose or throat, there will be millions of copies of its RNA that the machine will find, meaning you test positive. There are two reasons why you may test negative using this PCR technique. One is that you do not have COVID-19 and it is actually negative because the machine could not make copies of RNA that isn’t there to begin with. The other reason for a negative test is that the virus may not have replicated enough in the body to be found in the nose or throat at that time, even though you have the disease/virus. Many people who have had symptoms, tested negative despite having signs which were clearly related to COVID-19. After some time had passed, they were retested and were then positive. This can happen however your primary care provider and those working in healthcare know how to recognize the symptoms and clinically diagnose COVID-19 without the test (however PCR RNA testing is the best method to confirm this). The test itself is a little uncomfortable. When they swab inside your nose, they have to go all the way back, deep into your nose which sometimes feels like they’re tickling your brain and makes you feel like you are going to cough or sneeze. The throat swab is similar to testing for strep throat in which the back of the throat is swabbed and may cause gagging or coughing. It is not painful but certainly not pleasant. This test will tell you if you currently have the the virus and are infected. Once your symptoms disappear and you recover, your test will be negative.

The second type of testing, is called antibody testing. When you are sick with a virus or bacteria, your body creates proteins which circulate in your blood and attack, block, and neutralize the invader. The body has special immune system cells which create these antibodies. An analogy of this is a wanted poster. Your immune system takes a picture of a virus or bacteria the first time it sees it so that in case it comes back, it knows that it’s trouble and to watch out for it. The antibodies are these wanted posters. There are a few different types of antibodies however there are three that are being used for this type of testing: IgM, IgA, and IgG. IgM antibodies are made quickly and disappear quickly when first exposed to an infection. IgA antibodies are found in mucous membranes (typically where bacteria/viruses live). IgG antibodies are long lasting antibodies that serve as the wanted posters for future infections. Only recently has antibody testing for COVID-19 come about which raises a lot of questions. Many are not approved by the FDA (Food and Drug Administration which regulates all tests and medications) which could mean that these tests do not work well. Typically this is collected via a finger stick blood sample like checking a blood sugar or having blood drawn like you normally would for your cholesterol. The test works by having a piece of material soaked in a special chemical with proteins identical to those found on the virus. When the blood comes into contact with the material, if there are antibodies in your blood, they fit like a key into a magnetic lock and the test is positive. Sometimes however, there are other proteins in the blood which may cause a positive test (known as a false positive). An example of this are those with rheumatoid arthritis they may have a false positive because a rheumatoid factor protein in their blood sticks to the material instead. Another downside to this form of testing is that we don’t know what it actually means to have a positive IgG result. Can you get the virus again? Are you actually immune? How much IgG is considered protective, if at all? Can you still transmit the virus to others? These questions are being investigated so its use is very limited. The only use it may serve is to confirm a suspected case in the recent past or for those who had COVID-19 and want to donate their plasma for possible treatment. Other than that, it is hard to argue for its use in the general public other than saying who may have had the virus or been exposed to it.

PCR Testing:

Pro: Confirms active infection

Con: If not correctly obtained, a test could be negative. It is uncomfortable. If tested too early, test could be falsely negative. High risk of exposure for getting COVID-19 when collecting.

Antibody Testing:

Pro: Quick and easy to obtain without risk of exposure of getting COVID-19 when collecting. May show immunity (however needs more research behinds this).

Con: Unreliable results and not much is known about what the results mean and how it could be used as we don’t know enough about it.

At the end of the day, testing is great and we need to ramp up our supplies. Further research needs to be conducted regarding antibody testing. Before going to a testing center, call your primary care provider to make sure it is appropriate to be tested in case supplies are limited in your area. Be safe everyone!