Here is what you need to know about COVID-19 testing

There has been A LOT of talk about different types of tests and a need for testing during this coronavirus pandemic. It can all get a bit much and a bit confusing. So, over on my Instagram I have shared some posts breaking down the differences between the tests that the UK government are talking about, what they can tell us and why they are important. But I wanted to share that info over here on the blog too which is the purpose of this post.

As always if you have ANY questions about coronavirus testing or anything else related to the pandemic – do let me know so we can break it down together.


View this post on Instagram

Let's talk about COVID19 testing 🧪 . There has been a lot of talk recently, especially in the news here in the UK, about tests for coronavirus. So I thought I would share more about what all these tests might look like. . Let's start with current tests… . These are telling us if we have the virus by detecting any virus RNA. Swabs are taken and those samples are sent to the lab. Scientists then extract the RNA from the sample before it is converted into the more stable DNA 🧬. Then the DNA is mixed with small molecules called primers. These are little DNA sequences that are designed to bind to specific sections of, in this case, coronavirus RNA. It then goes through multiple cycles of heating 🔥 and cooling ❄ to create multiple copies of the DNA. I'll leave out the technical details this time… . Fluorescent dye molecules then get incorporated in each cycle as the virus DNA is multiplied. So, if the virus RNA is present ✔, the fluorescence grows and is detected over a certain level. A sample without any virus RNA ✖ means there is nothing for the primers to stick to and nothing to copy so there is no fluorescence signal above the limit. . BUT there are some issues with this: 🧪 Reagents need to be designed specifically and the high demand means testing is delayed in some countries ⏳ This method is time consuming. When I ran similar protocols in the lab, it could take me nearly two days to get a result. This obviously affects the number of tests that can be done, even though there are many scientists volunteering their time to help with testing ✔✖ This method is 100% efficient. Sometimes contamination or sample degradation can affect whether the result comes out positive or negative and sometimes tests will need to be done again. . This being said, I still think there is more we could be doing in the UK to do more tests and I hope that we will start to see those increases soon. . If you have any questions about how these tests work please ask questions below. And I want to talk about other tests and how they work in the next post or two this week. So again if you have any questions let me know in the comments. . As always stay home and stay healthy . . 💕

A post shared by Dr Soph🌻|Science communication ( on


View this post on Instagram

Let's talk coronavirus testing 🧪 Part 2 . There has been a lot of talk about coronavirus testing recently. Especially here in the UK. In my previous post, I spoke about the current tests that are going on. These tests are ones that can tell you if you have the virus and are are infected right now! . But what about those who have maybe had the virus and gotten over it? That requires a different type of test that I want to tell you about… . When we are exposed to bacteria or viruses, our immune system kicks in and launches a response to the invaders. Our body produces antibodies that bind to proteins or other molecules on the surface of the invaders! The antibodies bind onto those molecules and destroy the virus or bacteria. Think of it like a lock and a key. . These antibodies stick around in our bloodstream for a little while after we have had an infection, so we can test whether someone may have had the coronavirus infection by detecting any antibodies. . These tests are faster but not quite as accurate. One of the reasons for that is because coronaviruses are a family of viruses, some of which we may have been exposed to before, so tests are currently not smart enough to work out which antibodies are specifically from this current coronavirus over others. . But there are currently other tests that many other companies and academic researchers are working on too. But these are the two types of tests our government are referring to – the current tests I shared more about yesterday and the antibody test here. . If you have any more questions about coronavirus testing, please feel free to ask in comments or DMs . Stay safe and healthy everyone . . 💕

A post shared by Dr Soph🌻|Science communication ( on

If you liked this post, then you might also like…

One thought on “Here is what you need to know about COVID-19 testing

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s