What is an ELISA test ?
An enzyme-linked immunosorbent test, also called an ELISA or EIA, is a test that detects and measures antibodies in the blood. This test can be used to determine if you have antibodies related to certain infectious conditions. Antibodies are proteins that your body makes in response to harmful substances called antigens. An ELISA test may be used to diagnose:
- HIV, which causes AIDS
- Lyme disease
- pernicious anemia
- Rocky Mountain spotted fever
- Rotavirus
- squamous cell carcinoma
- syphilis
- toxoplasmosis
- varicella-zoster virus, which causes chickenpox and shingles
- Zika virus
ELISA is often used as a screening tool before ordering further testing. A doctor may suggest this test if you have signs or symptoms of the above conditions. Your doctor can also order this test if you want to exclude any of these conditions.
The ELISA test involves taking a sample of your blood. First, a health professional will clean your arm with an antiseptic. Then, a tourniquet or band will be applied around your arm to create pressure and make your veins swell with blood. Next, a needle will be placed into one of your veins to take a small blood sample. When enough blood has been drawn, the needle will be removed and a small bandage will be placed on the arm where the needle was. You will be asked to maintain pressure at the site where the needle was inserted for a few minutes to reduce blood flow. This procedure should be relatively painless, but your arm may throb a little after it’s done. The blood sample will be sent to a laboratory for analysis. In the laboratory, a technician will add the sample to a Petri dish containing the specific antigen related to the condition for which the test is being performed. If your blood contains antibodies to the antigen, the two will unite. The technician will verify this by adding an enzyme to the Petri dish and observing how your blood and antigen react. It can have the condition if the content of the plate changes color. The degree of change caused by the enzyme allows the technician to determine the presence and amount of antibodies.
There are very few risks associated with this test. These include: infection, feeling faint, bruising, bleeding more than usual.
What do the results mean?
The way test results are reported varies depending on the laboratory performing the analysis. It also depends on the condition for which the test is performed. Your doctor should discuss your results and what they mean. Sometimes a positive result means you don’t have the condition. False positives and false negatives can occur. A false positive result indicates that you have a condition that you do not actually have. A false negative result indicates that you do not have a condition when you really do. For this reason, you may be asked to repeat ELISA again in a few weeks, or your doctor may order more sensitive tests to confirm or refute the results.
NLSIU Bengaluru to Launch 3-Year BA (Hons) Programme in 2025 | Key Details
CUET-UG to Be Fully Online: Key Changes Announced by UGC
D.Pharma Course in India | Careers After Class 12th
The Draft UGC (Minimum Standards of Instructions in the Award of UG and PG Degrees) Regulations 2024 | A Comprehensive Overview
Challenge CAT 2024 Answer Key | Objection Deadline Ends December 5
CLAT 2025 Counselling Begins December 11 | Key Dates, Steps, and Seat Allotment Explained
CLAT 2025 Answer Key Released: Key Details and How to Download
CLAT UG, PG 2025 Exam Tomorrow | Last-Minute Strategies and Key Details
Registration for CLAT 2025 begins today; last date October 15
CLAT 2025 registration will begin on July 15
About Post Author
More Stories
CUET-UG to Be Fully Online: Key Changes Announced by UGC
The Draft UGC (Minimum Standards of Instructions in the Award of UG and PG Degrees) Regulations 2024 | A Comprehensive Overview
Challenge CAT 2024 Answer Key | Objection Deadline Ends December 5