BioQuakes

AP Biology class blog for discussing current research in Biology

Author: lindsosomes

Testing!

When you hear the word “COVID -19 testing” what comes to mind? I have this vivid image of a cotton swab being pushed up my nose. But what exactly is testing? Why is it so important? And what are the types of testing available for our use?

We’ve all heard that testing is important but why? To summarize a supplementary article, COVID testing “leads to quick identification of cases, quick treatment for those people and immediate isolation to prevent spread” (Dr. Eduardo Sanchez). When discovered at an early stage, COVID will be less a threat to a person because doctors can plan accordingly while COVID is still less severe. Even when a person discovers they have COVID not as early as hoped, testing helps to identify anyone who came into contact with infected people so they too can be quickly treated. Contact tracing would not be possible without testing because a person would never know if they are spreading the virus. The only way to be better safe than sorry is to get tested. Someone may show symptoms that are COVID-like but there is still a chance that it could be a common cold, or allergies. It is important to confirm COVID suspicion.

Now that we know why testing is important, what kind of testing is out there? What I found in this FDA article is what I like to call a family of tests; there are numerous different tests to take.

To start things off, let’s talk about Diagnostic testing. Diagnostic testing shows if you have an active coronavirus infection. As of right now, there are two types of diagnostic tests: molecular and antigen tests. Molecular tests detect the virus’ genetic material in a sample from the patient’s nose or throat. This is where test results will take longer because they are sent to labs. From there, the lab essentially converts the virus’s RNA into DNA, and then make millions of copies of the DNA to be processed in a machine. The test is “positive” for infection with SARS-CoV-2, the virus that causes COVID-19. Examples of molecular diagnostic tests include nucleic acid amplification test (NAAT), RT-PCR test, and the LAMP test. Next, there is Antigen diagnostic testing. Antigen tests provide results from an active coronavirus infection faster than molecular tests. The downside to these tests are that they have a higher chance of missing an active infection. Sometimes an antigen test may come back negative, but a doctor might still order a molecular test to confirm.

Different from Diagnostic Tests, there are Antibody (different from Antigen) tests. These tests looks for antibodies that are made by your immune system in response to a threat, such as a specific virus. As we learned in biology class, antibodies can help fight infections. These tests are taken by finger stick or blood draw, and the results are quick. The antibody test only shows if you’ve been infected by coronavirus in the past. But do antibodies help diagnose COVID-19? As we learned in class about the Immune System, our body can fight pathogens, bacteria, and viruses that we have been previously exposed to. While this was a popular belief earlier on in the year, sadly, researchers do not know if the presence of antibodies means that you are immune to COVID-19 in the future. It is possible to contract COVID-19 for a second time, therefore adaptive immunity does not apply.

The most common testing that I knew of before researching was rapid testing. Rapid testing can be both a molecular or antigen diagnostic; a doctor uses a mucus sample from the nose or throat. The test can also be taken at home only by prescription of a doctor. The results are available in minutes. There is also saliva testing where a person can spit into a tube; this also keeps the doctor or worker safer from the potentially infected person.

Testing is the best way to keep yourself and those around you safe. While testing is still not 100% accurate, there is currently no better way to confirm if someone has COVID-19 unless he/she get tested. With this pandemic, we can never be too safe!

 

 

 

 

 

Can your common cold help you beat vicious COVID-19?

Season colds are quite common, and while they are inconvenient and make us feel icky, they may be our advantage for our battle with COVID-19. 

To start off, when reading this article, I noticed that the author used the term “coronavirus” more casually. He referred to a “coronavirus” as a common cold, which of course left me confused. So I dug a little deeper…

Here’s a fun fact that I learned from this:

Many of us having been thinking that COVID-19 is the same as what we call the “coronavirus.” After reading an article differentiating the difference between the terms, I found that the term coronavirus is actually the broad term to describe a whole range of viruses. SARS-CoV-2 is the specific virus that causes only COVID-19 and is causes what doctors call a respiratory tract infection.

Basic biology tells us that while there are many cells that make up our body, they are all interconnected. A pathogen, like the SARS-CoV-2 virus, is an enemy to the cell. We learned about how things enter the cell in biology: the pathogen enters the cell, travels through the cytoplasm, and enters the nucleus. Because the virus has genes, it is able to rapidly produce copies of itself to infect the other cells. And of course, we know how scary these infected cells are when they start spreading to the lives around us given our situation with a global pandemic.

What we now know is that the SARS-CoV-2 virus, our “bad guy,” can actually induce memory B cells. These memory B cells survive for quite a long time; they are important in identifying pathogens, and creating antibodies to destroy such pathogens. So when we got sick during the winter last year, chances are these memory B cells fought them off. The key part of the memory B cell in our fight against COVID-19 is the cell’s ability to remember the antibodies it created from past illness for the future.

What does this mean?

The belief is that anyone infected by COVID-19 already has the memory B cells from past common colds to fight the virus off.  Taking a further step, it is believed that since everyone already has the memory B cells, anyone who has had COVID-19 in the past is unlikely to get it a second time. If the SARS-CoV-2 virus were to enter your body a second time (which is likely considering the virus has not gone away and is literally all around us), our bodies would be prepared with former knowledge of the antibodies used to fight and win this time.

A study performed at the University of Rochester Medical Center is the first to demonstrate how this may be so.

Mark Sangters, Ph.D., is a research professor of Microbiology and Immunology at URMC; he has backed up his findings by comparing different blood samples. When looking at 26 blood samples of recovering moderate COVID- 19 patients (people who have had it for their first time now), it seems that many of them had a pre-existing pool of memory B cells that could recognize the SARS-CoV-2 virus and rapidly produce antibodies to destroy it. He also studied 21 blood samples of healthy donors, collected years before COVID-10 existed. What he found was that these B cells and antibodies were also already present.

When we are sick with a common cold, our antibodies are created by memory B cells to attack the Spike protein. This protein is what helps viruses infect our cells. What Sangters noticed, is that although each Spike protein is different for each illness, the S2 portion of the Spike protein is the same throughout all sickness. Our antigens can not differentiate the parts of the S2 subunit, so they attack the Spike protein regardless. This was his final piece in his conclusion that our common colds that caused our memory B cells to make antibodies, could be used to fight against COVID-19.

The Long Road Ahead:

My concern with this article is that this is the biggest issue we face with COVID-19 is patient outcome. As of right now, there is no way to fully prevent everyone from COVID-19 because it is still all around us. The issue the world is facing, is how to treat those who have already contracted the virus. This information just simply is not enough to help. How will these memory B cells help those who are currently sick? The answer: Scientists are unsure. There is still the uncertainty of the future vaccine and study of these memory B cells for a possibility of milder symptoms or shorter length of illness from COVID-19.

 

Despite all of this concern, this is still a step in the right direction. Any information about this terrorizing virus is still helpful given how little we know about COVID-19. If we were to expand more on this information, we could save the lives of those around the world!

 

 

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