Definition

Rubeola, commonly known as measles, is a viral infection that infects cells located in the lungs and the throat. This infection is highly contagious and can be easily transmitted through coughing, sneezing, or touching a virus-contaminated surface and subsequently contacting the mouth, nose, or eyes. Although the infection typically subsides within a few days, there are rare instances in which it can lead to severe complications. Through vaccination, it can be prevented. 

This article will focus on the procedure for detecting antibodies in circulation. Antibody testing identifies the antibodies that the immune system produces in response to a vaccination or measles infection. We can use this testing to determine an individual's immunity status, pinpoint an active case, or track outbreaks.

The antibodies produced in response to measles virus fall into two categories:

• IgM, or immunoglobulin M, is the initial form of antibody that is generated in response to measles vaccination or infection. Over the course of the following weeks, the concentration of IgM antibodies exhibits a gradual increase over a span of several days, reaches its highest point, and gradually decreases.
• IgG, or immunoglobulin G, is synthesized at a later stage, but once it forms, it persists in the body indefinitely, providing lifelong protection against subsequent reinfections. 

Occasionally, two blood samples are obtained with a significant time gap between them (acute and convalescent samples), and the concentration of antibodies is assessed and compared. This approach may aid in distinguishing between a current infection and a previous infection.

We also have an article on measles which you can read here: Measles - Definition, Causes and Risk Factors.

Indication

When you exhibit classic measles symptoms or if you have recently come into contact with infected people and are experiencing symptoms that might possibly be caused by measles, your doctor might suggest a measles test that measures IgM and IgG antibodies.

The production of IgG antibodies provides protection against future measles infections, typically for life. This test is taken to help detect the presence of measles IgG antibodies in the blood.

This diagnostic test is valuable for assessing the immunological response to the measles virus. The antibody test might be requested by your physician to figure out your immunity to this virus, either as a result of a prior illness or measles vaccine that you have got in the past.

One may require a measles IgG antibody test to assess their immunity to measles in the event that:

• They are currently pregnant or intending to conceive
• They are planning to attend a school or university, or begin a career that necessitates providing evidence of their immune status to measles
• They are healthcare professionals who could come into contact with patients who have measles

In cases where multiple individuals may have come into contact with people infected with measles and they are either not vaccinated or exhibiting the aforementioned symptoms of measles, measles antibody tests could also be requested, especially if a measles outbreak within the region is suspected or verified. The tests facilitate the identification of new and current measles cases, enabling public health officials to implement measures aimed at slowing and stopping the transmission of the disease.

Contraindication

There are no individuals for whom it is advised against to check their serum measles IgG level; everyone is eligible to undergo blood tests for monitoring the levels of measles IgG in their bodies.

Preparations Prior to Test

No specific preparations are required before you take this test. It is important that you inform your physician about the medicines or supplements that you are currently using. Depending on the instructions of your physician, you may or may not be required to discontinue any of these medications prior to the test.

Test Procedures

A healthcare professional will extract a blood sample from a vein, usually in your arm, using a tiny needle. Once the needle is placed, a little sample of blood will be drawn into a test tube. You may experience a slight stinging sensation when the needle is inserted or removed.

In the case of taking a sample from infants, the blood sample can also be obtained from the capillary blood in the heel. 

Normal and Abnormal Values

The reference value of this is relevant to individuals of all age groups.

• Unvaccinated individuals exhibit a negative result 
• Vaccinated individuals get a positive result

The presence of measles IgG antibodies in the body indicates exposure to the measles virus, either through vaccination or infection. Individuals with positive test results are regarded to possess immunity against measles infection. Conversely, the absence of measles IgG antibodies indicates either the absence of an immune response to vaccination or that they were not exposed to the measles virus previously.

Results and Suggestions (Follow-Up Tests)

Measles IgG antibodies are usually found in individuals who have had vaccinations or prior measles infections, and are currently not infected. This means that they have immunity against the measles virus. Individuals lacking measles IgG antibodies are not regarded as having immunity to the virus.

This table summarizes the results of measles antibody tests:

Consult to The Right Doctor

Measles is typically diagnosed solely based on symptoms and clinical findings. Screening for measles IgG antibody could help in identifying individuals with no immunity to this virus.

For the best explanation of your test results, consult your physician or internist. The process of interpreting the test requires careful consideration of both the test results and one's overall health, risk factors, and symptoms.

Want to know more information about laboratory, radiology and other examination results? Click here!