Question

Discuss one of the following:

Why would you NOT take blood pressure on the right arm of a person with a right mastectomy and sentinel lymph node biopsy?

or

Why is the ELISA test called a "sandwich prep?"

or

What is the difference between PCR testing and ELISA testing for COVID-19?

Answer 1

Difference between PCR testing and Elisa testing

PCR, (Polymerase chain reaction) Majority of the current Covid-19 tests that all the reports are coming from are using PCR, these tests detect the genetic information of the virus, the RNA. That’s only possible if the virus is there and someone is actively infected. This test uses a sample of mucus typically taken from a person's nose or throat. The test may also work on saliva. PCR tests are used to directly detect the presence of an antigen, rather than the presence of the body’s immune response, or antibodies. By detecting viral RNA, which will be present in the body before antibodies form or symptoms of the disease are present, the tests can tell whether or not someone has the virus very early on.

Disadvantage of this test are, few days may pass before the virus starts replicating in the throat and nose, so the test won't identify someone who has recently been infected and the other problem are swabs can sometimes fail to pick up signs of active infection, hence there chances that they can give false negative results.thew other disadvantage is that it can take several days to get results back.

Elisa, Enzyme linked immune assay test,  these tests checks whether or not you have antibodies in your blood to the new coronavirus that causes COVID-19. Your body produces antibodies in response to an infectious agent such as a virus. These antibodies generally arise after four days to more than a week after infection, so they are not used to diagnose current disease. Antibody tests identify people who have previously been infected with the coronavirus. They do not show whether a person is currently infected. This is primarily a good way to track the spread of the coronavirus through a population.

The main advantage of this test is that, these tests generally produce results in a few minutes, in this test a drop of blood is taken from your finger rather than a throat swab.These test can give esearchers a more accurate measure of how many people had the new coronavirus.