Covid testing – Simple Guide About Testing in ST Andrews

The SARS-CoV-2 virus (Coronavirus)

The odds are that by now; you are very well of this virus and its variants that infected people globally. In 2019, In Wuhan, China people started experiencing respiratory problems from a newly identified virus, and soon the virus spread all over the world. On 31 December 2019, the World Health Organization officially learned of this new virus, following a report on the outbreak in China. The rest, as they say, is history.

The virus has infected people on all the continents, even Antarctica! There are many theories as to the origin of the virus, but the most popular that most scientists agree on at the moment, is that it was transmitted via animals in a wet market in Wuhan, China. Bats that was available for purchase and slaughter at the market, are known to be natural carriers of corona viruses and the theories suggest that this was where the first transmission happened.

From patient zero (the first person identified with the virus) the virus was transmitted to other people and which in turn set off a chain reaction of infections that led to the global pandemic. The virus primarily spreads through droplets of saliva or mucus from the nose when an infected person sneezes or coughs. It can also be transferred from surfaces where an infected person left saliva or mucus behind through touching, coughing, or sneezing.

As of July 2021, according to the WHO there have been 196 million confirmed cases with 4.19 million fatalities. In the United States alone, 34.8 million have been infected and 612,000 passed away because of COVID-19 related complications. 

Testing/Screening options for COVID-19

There are various tests that could determine if a patient is COVID-19 positive and in this section, we would like to explain more about the different tests that are available to you, the differences between them and what to expect when you go for a screening.

Tests for Covid-19 can be divided into antigen or antibody tests, and they search for different signs of the virus. An antigen is a substance that causes the body’s immune system to respond against that substance. Antigens include toxins, chemicals, bacteria, viruses, or other substances that come from outside the body. Once the body detects a threatening substance such as the ones mentioned above, the body sends antibodies to fight these intruders.

That means that the two categories of tests mentioned above, look for evidence of the virus itself, or antibodies in the body that would suggest that the body detected the virus already. 

PCR Tests

A polymerase chain reaction (PCR) is a test that will recognize if you are infected with the virus during the time of testing. The test specifically looks for the genetic material from an organism such a virus; or antigen, as explained above. Even after you are no longer infected, this test can detect little pieces or fragments of the virus that was present in your body. This test is the most reliable and widely used test to detect COVID-19.

The test is performed by inserting a cotton swab up (a thin plastic stick with a soft cotton head) , into the nasal cavity. Here, mucus and saliva are collected on the head which is then removed and placed into a plastic tube that is sent to the laboratory for testing.

When the laboratory receives the sample, they extract the genetic material using specific chemicals, and a machine called a thermal cycler. In short, during the process, one of the chemicals will produce a fluorescent light if the COVID-19 virus is present and the computers pick up this signal and notify the observer that the result was positive.

A positive result means that the patient who was tested most likely is , or was, infected with the virus during the time of testing. 

Rapid Antigen Test

This test is also known as the Rapid Antigen Test or Rapid Test for short. These tests are fast, as the name suggests, and is easy to perform. They detect proteins of the virus and the results are available almost immediately. They are both cheaper and faster than PCR tests but they are also internationally regarded as being less reliable than the PCR tests. The results could lead to false negatives. That means that the test may display that a person is not infected with the virus, where the person indeed is infected.

The Rapid Antigen Test is very useful to detect the virus in people who are displaying symptoms already. Many practitioners use these tests to determine if the patient is infected with a flu virus or COVID. When the patient is already displaying symptoms, it means that the virus produced sufficient protein to be detected by the test.

The initial phase of testing is the same as the PCR test. A cotton swab is inserted into the nasal cavity or back of the throat and a sample is collected. Instead of sending the sample off to the lab, it is placed on a small disposal device that then detects the presence of the proteins and displays the results almost instantly. 

Covid Antibody Test

This blood test is also known as serology testing and tests for antibodies that the body may have produced in reaction to an intruding organism in the body as explained in the first section of this article. This test determines if the patient is infected or was infected before and recovered. This test is not suitable to detect a current COVID infection in the body.

Unfortunately, it can’t determine if the patient is now immune to the virus or how long they will remain immune. It is therefore not recommended that people should do an antibody test after receiving their COVID-19 vaccinations. Also, not all the antibody tests on the market that are on offer to the public, have been approved by the FDA, so make sure that if you decide to test yourself that the test was FDA approved.

But why would you want to get an antibody test if you are no longer sick? Doctors could suggest that you get an antibody test if your viral test was negative. Alternatively, if unexplained symptoms are occurring in your body, the antigen test could determine if the symptoms are COVID-related complications due to an infection you had before.

If you have antibodies in your system, you might be eligible to donate plasma to people that are are really sick due to COVID-19. 

When should you get tested?

According to the World Health Organization, there are common symptoms and less common symptoms and serious symptoms. It is advised that you watch out for all of these.

The most common symptoms include

• Fever
• Dry cough
• Fatigue/ Tiredness 

The less common symptoms include

• Aches and pains
• Sore throat
• Diarrhea
• Conjunctivitis
• Headache
• Loss of taste or smell
• A rash on the skin, or discoloration of fingers or toes 

Serious symptoms:

• Difficulty breathing or shortness of breath
• Chest pain or pressure
• Loss of speech or movement 

If you have serious symptoms, you should seek immediate attention. Contact your physician or go to the hospital as fast as possible. On average it takes 5–6 days from when someone is infected with the virus for symptoms to show, however it can take up to 14 days. If you have mild symptoms, stay home and prevent others from getting infected, but make sure that you are positive. You may just be having a cold.

Covid testing at St. Andrews Medical Center, Los Angeles

It is important to know your status if you have Covid symptoms. For one, you need to stay alert and be aware in case your symptoms become more severe. You will be well aware of your status and would not hesitate to seek immediate medical attention as is recommended.

Many people might display Covid symptoms, but they are not infected. In these instances, it is better to get tested and if the results are negative, they can still continue with their lives without going into isolation, missing work, etc. There are instances where employers might forbid an employee with symptoms to return to work without a COVID-19 negative test result.

Travelling has become increasingly more difficult over the last year and a half. Many countries forbid tourists and business people alike to enter the country without a negative PCR test that was administered within 72 hours of entry. If you plan to travel somewhere soon, you need to find out if a PCR test is required.

Whether you have symptoms, want to be on the safe side, need a negative test for working or traveling, you can get both the PCR test and Rapid Antigen Test at St. Andrew’s Medical Center in Los Angeles. Our facility is certified to administer tests and our expert staff use only certified testing equipment.

In consideration of your safety and convenience, you don’t even have to leave your car. We will administer the test while you are sitting behind the wheel of your car. This lowers your exposure and decreases the chance that you could be infecting others, or if negative, be infected by others.

Your Rapid Antigen results are available in 5 minutes and you would be on your way in no time. The more accurate PCR test results are available within 24 hours.

Contact our highly trained professionals at St. Andrew’s Medical Center for any additional information that you might need regarding COVID-19 or any other health related issues. 


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