How do Covid-19 Tests Work? 

In the modern-day and age, we are going through a global pandemic which means that we have to keep ourselves safe. One way in which the government is keeping us safe through the supply of testing kits and free tests to the public. These tests are crucial in determining whether a member of the public has to self-isolate to reduce the risk of others catching the virus or even to see whether they have passed the virus through the renowned ‘antibody’ test. This means that if someone has contracted the virus previously that it is now safe to resume traveling to work or going outside. Here in the UK, the NHS tests us for free when required and when we show even the slightest symptoms such as loss of taste and smell, cough, fever, vomiting, and many others. In this essay, I will be exploring how the use of chemical and instrumental analysis is being used to fight the pandemic.

One way that instrumental and chemical analysis is being used is through antibody tests. At the moment the antibody test is only supplied to the most essential workers and not to the wider public. When you are infected with coronavirus the body responds by creating antibodies as part of the body’s natural defense against the virus. Antibodies are produced once the virus is detected and binds to the antigens on the virus’s surface causing them to be marked for destruction. Either the phagocytes will engulf them and when they are marked that are not allowed to enter the cell. Viruses need a host to survive. A virus enters our cells and takes over the cells’ machinery, and the viruses replicate until they burst out of the cell and go invade other cells as they need the cell to replicate and spread. The test which is exclusively for essential workers means that the test identifies whether the antibodies are still in our bloodstream, it’s basically a blood test. Also if you have produced antibodies to the virus you are now immune and then it is safe for you to go back to work or roam around. Another way is through regular testing to determine whether you currently have the ailment or not. This test involves taking a swab from deep in a patient’s nasal cavity to collect cells. This is then sent to a lab to find traces of the virus’s genetic material in the cells. This is RNA. In the lab, the RNA is converted into DNA. The DNA is replicated many many times so that it can be detected. This is using a quantitative PCR instrument. Once the viral DNA is detected the results are sent to your home whether it has come out positive or negative. However, this test is not 100 percent accurate as sometimes the viral DNA may not be detected if the person is infected. But the success rate is relatively high.

Testing was extremely significant in the country’s and global way to fight coronavirus. If you know you have the virus you can stay at home and stop it from spreading. However, the real reason this disease spread owes credit mostly to the youth of our nation. The elderly have been very careful throughout the pandemic as they have seen the deaths at care homes and how coronavirus has been running rampant through these care homes and killing thousands across the globe. These elderly citizens typically have a weaker immune system as they get older, hence why the exponential death rate.

The stages of coronavirus are:

  • You contract the disease by inhaling it through your noses and mouths.
  • They find a place in the nose lining as the nose lining has a lot of ACE2 receptors which are beneficial for the virus as the virus needs ACE 2 to enter the cells.
  • After this, the virus uses the cells machinery to make myriad copies and then will spread
  • Not many symptoms are shown through the first week, but this is when the most virus is shed,(contributing to a very high R rate. Also many elderly experience symptoms in the first week.
  • If the immune system isn’t fighting back (typically in the elderly as they can have delayed immune responses) the virus moves down the windpipe to the lungs.
  • They reach the alveoli (the small air sacs in the lungs) which have even more ACE 2 receptors)
  • As the immune system fully kicks in it interrupts oxygen transfer. This is because white blood cells release chemokines to summon more cells to fight. This leads to a lot of pus left behind, clogging up the lungs.
  • This gets extremely dangerous as it gets to pneumonia, an extremely dangerous respiration ailment.
  • Some get ARDS and oxygen plummets even further. They end up on ventilators and from here the survival rate is very low
  • Most die if they reach this stage as the lungs are full of residue.

The reason why coronavirus has such a high spreading rate is because of the stigma that coronavirus mainly affects the elderly, and young people aren’t being careful enough and continue to roam around without wearing masks for non-essential things. The youth typically have a good survival rate and hardly show any symptoms as they have a strong immune system, but due to the lack of symptom display, they spread coronavirus without realizing that they may have had it. So eventually it can reach more vulnerable groups such as the disabled and elderly and have a much adverse effect on them as a result.

Angath Makan, Youth Medical Journal 2022


GOV.UK. 2020. Getting tested for coronavirus (COVID-19) – GOV.UK . [ONLINE] Available at: [Accessed 16 September 2020]. 2020. Antibody test to check if you’ve had coronavirus (COVID-19) – NHS. [ONLINE] Available at: antibody-test-to-check-if-youve-had-coronavirus/. [Accessed 27 August 2020].

Virus Wars. 2020. Virus Wars. [ONLINE] Available at: viruswars/viruses.php#antibodiesstrikeback. [Accessed 27 August 2020].

Chemistry World. 2020. Explainer: The science of Covid-19 testing | News | Chemistry World. [ONLINE] Available at: covid-19-testing/4012078.article. [Accessed 27 August 2020].

GOV.UK. 2020. Coronavirus (COVID-19): getting tested – GOV.UK . [ONLINE] Available at: [Accessed 27 August 2020].

Centers for Disease Control and Prevention. 2020. Testing for COVID-19 | CDC. [ONLINE] Available at: [Accessed 16 September 2020].

COVID-19 diagnostic testing – Mayo Clinic. [ONLINE] Available at: https:// [Accessed 16 September 2020].

Written by Angath Makan, a budding scientist at a high school in England who regularly writing scientific articles on topical issues. This article was specifically based upon the science behind the Covid-19 tests and how they help to keep us safe.