PCR stands for "polymerase chain reaction." It is a test that can be used to detect the presence of genetic material from the virus. The PCR test looks for actual genetic material from the virus, while an antibody test looks for antibodies produced by your body in response to infection with SARS-CoV-2.
A PCR test is used to identify a current, active case of the virus. It's also sometimes called the "gold standard" for HIV testing because it's so sensitive that it can detect even miniscule amounts of the virus in your bloodstream.
In this section, you'll learn all about PCR and how it works: why it's important; what it looks like in action; who uses PCR; and more!
PCR tests look for specific genetic material from the virus. The virus itself is not detected, but instead, DNA sequences specific to SARS-CoV-2 are searched for by the test. Because this method identifies only the presence of genetic material, it can be used to confirm an active case of SARS-CoV-2 in someone who has tested positive on an antibody test.
This method is usually done in a laboratory setting using equipment that allows researchers to amplify (make more) certain sections of DNA and then analyze them using gel electrophoresis or other methods.
A positive PCR test result can be used to diagnose infection with SARS-CoV-2 and allow for public health monitoring to begin.
PCR testing of blood specimens from patients with suspected SARS cases has been found to be highly specific (99%) and sensitive (96%).
Public health officials use the results of their tests as evidence that a person is infected with the virus, which will allow them to begin transmitting it through the air and prevent any further spread of the disease.
If a person tests positive for COVID-19, public health officials will try to determine close contacts the person may have had so those contacts can isolate themselves or get tested for COVID-19. This is done by interviewing people who were around the infected person in the days before they developed symptoms of illness.
When it comes to testing, there are two main types: antibody tests and polymerase chain reaction (PCR) tests. Antibody tests look for antibodies that your body has created to fight off an infection. They are used when you are at risk of having been exposed to a virus or bacteria but have not yet shown symptoms of illness. These include blood and saliva samples that can be taken in a doctor's office or other setting where medical equipment is available.
Antibody tests are not as sensitive as PCR tests; this means they miss more cases of infection than PCR because many people with an early stage of COVID-19 infection don't have enough virus in their system yet for it show up on these types of exams
For example, if someone has been diagnosed with COVID-19, public health officials will try to determine close contacts the person may have had so those contacts can isolate themselves or get tested for COVID-19. This helps stop the spread of COVID-19 if people don't have symptoms but are still contagious.
PCR tests are done in a laboratory and can take longer than other tests to get results.
PCR test results can be used to identify a current case of the virus, but they aren’t useful for identifying past infections.
PCR is used to identify a current, active case of the virus. A rapid test can be done in minutes, but it's only good for detecting whether or not someone has been infected with a specific strain of the SARS-CoV-2 virus within the past two weeks. If you've been exposed to one strain of SARS-CoV-2 and tested negative for other strains, then another test might be needed if that's what you're looking for.
The PCR test is performed in a laboratory setting by an experienced professional who will take samples from your nasal passages and throat swabs before testing them in order to determine whether or not they contain traces of viral DNA (the genetic material found inside all living things). Like other types of tests, this one takes time because it has multiple steps: First they have to develop antibodies against certain proteins inside your body; then these antibodies attach themselves onto tiny bits called antigens before being sent off into solution where they'll bind themselves onto any viruses floating around nearby; finally those bound molecules are washed away so scientists can see what kind of results came back positive/negative based on how many cells were able think out loud about their feelings towards each other."
The PCR test is used by public health officials to actively isolate instances of infection. This helps stop the spread of COVID-19 if people don't have symptoms but are still contagious. The PCR test is done in a laboratory and can take longer than other tests to get results.