Cytomegalovirus (CMV) Tests

Cytomegalovirus (CMV) tests check for signs of CMV in your blood, sputum, or other body fluids. CMV is a virus in the herpes family. Other types of herpes viruses include the viruses that cause chickenpox and mononucleosis (mono).

CMV is a common virus that infects people of all ages. Most people have been exposed to CMV during childhood. Once you get a CMV infection, the virus stays in your body for the rest of your life.

Most of the time, the virus stays dormant (inactive). However, it can become active again (reactivated) in certain situations, such as when you are under a lot of stress or if you have an immune system problem. If the CMV virus is active, it can be spread through body fluids such as: Saliva; Urine; Blood; Tears; Semen; Breast milk; Most healthy people don't have any signs or symptoms when they get CMV.

They usually aren’t even aware that they have the infection. But sometimes a CMV infection may cause mild, flu-like symptoms in healthy people. However, certain people are at higher risk of health problems from a CMV infection: People with weakened immune systems due to conditions such as HIV or cancer.

For them, CMV can cause vision problems and other serious health problems.; If you are pregnant and have an active CMV infection you can pass the virus to your fetus. In severe cases, this could lead to the loss of the baby through a miscarriage or stillbirth.; Newborns who got a CMV infection before they were born. This type of CMV is known as congenital CMV.

Most babies born with CMV do not have health problems from the virus. Of the babies that do, the most common long-term health problem is hearing loss. Congenital CMV can also cause vision problems, intellectual disabilities, and other serious disorders. ; Very low birth weight and premature infants.

They can get a CMV infection during childbirth or from breastfeeding. They are less able than healthy babies to fight the infection.; CMV testing can help those at risk for complications get the treatment they need. While there is no cure for CMV, antiviral medicines and other treatments may reduce your symptoms and improve outcomes.

Why this test is done

You may need testing if you have a weakened immune system or are pregnant and have the following symptoms:

• Swollen lymph nodes ("swollen glands")
• Sore throat
• Fever
• Fatigue
• Weakness
• Muscle aches
• Headache

Your baby may need this test if they have the following symptoms:

• Jaundice, a condition that causes your skin and eyes to turn yellow
• Low birth weight
• Small head
• Hearing and/or vision problems
• Seizures
• Rash

How to prepare

You don't need any special preparations for a blood or sputum test. There are also no preparations needed for an infant saliva or urine test.

You may need to empty your bladder before a spinal tap.

You may be asked to fast (not eat or drink) for several hours before a biopsy.

For an amniocentesis, you may be asked to not urinate (pee) before the test to make sure you have a full bladder. This helps move the uterus into a better position for the test. In later pregnancy, you need to have an empty bladder for the test.

Your provider or your child's provider will let you know if you need to make any other preparations.

Sample type

Blood Urine Saliva CSF Tissue/Biopsy

Other names for this test

CMV IgG and IgM, cytomegalovirus antibody