Cytomegalovirus

Cytomegalovirus

Overview

What is cytomegalovirus?

Cytomegalovirus (say: si-toe-meg-ah-low-vi-russ), or CMV, is a very common virus. People are usually infected by the time they are 2 years old or during their teenage years and carry the virus for life (usually in a dormant or inactive state). The majority of adults carry the virus by the time they are 40 years of age.

Many people are infected with CMV and don't even know it because the virus rarely causes symptoms and usually does not cause long-term problems.

However, CMV can cause problems in people who have weak immune systems and in a newborn if the mother gets the infection during pregnancy.

Symptoms

What are the symptoms of CMV?

Usually, CMV does not cause symptoms or only causes mild symptoms. A few people will have symptoms that are similar to mononucleosis. Symptoms of CMV can include:

  • Sore throat
  • Swollen lymph nodes (lymph glands)
  • Fever
  • Headache
  • Fatigue
  • Weakness
  • Muscle aches
  • Loss of appetite

People who have weakened immune systems due to conditions like human immunodeficiency virus (HIV) or because they received an organ transplant and are taking immunosuppressant medicines may have severe symptoms. (Immunosuppressant medicines are medicines that lower or suppress the immune system.) Symptoms of severe CMV include:

  • Blindness
  • Pneumonia
  • Diarrhea
  • Bleeding ulcers in the esophagus (windpipe) or intestines
  • Inflammation of the brain (encephalitis)
  • Seizures

CMV is more likey to cause vision problems in people who have weakened immune systems, so if you have conditions such as HIV or AIDS, your doctor may recommend that you visit an eye doctor to find out whether the virus has infected your eyes. Be sure to let your doctor know if you are having any painless blurring of your vision, "floaters" only in one eye, light flashes or areas of blindness. You should also let your doctor(s) know if you are experiencing frequent shortness of breath with flu-like symptoms, or if you are having problems hearing.

Causes & Risk Factors

How is CMV spread?

CMV gets into body fluids, such as saliva, blood, urine, semen and breast milk. A person is able to transmit (or "shed") the virus to others only when it is active in his or her system (not dormant). It can be spread from one person to another through sexual contact and contact with blood and other body fluids. CMV can rarely be transmitted by blood transfusion or organ transplantation.

In child care centers, as many as 70% of children ages 1 to 3 can shed the virus. Careful, frequent hand washing with soap and water may help prevent the spread of CMV.

Diagnosis & Tests

How will my doctor know if I have CMV?

CMV is diagnosed with a blood test.

If you are pregnant, your doctor may want to test you for CMV to determine if there is a risk for your unborn baby. If you do carry the virus, your doctor may suggest a test called amniocentesis, which collects a sample of the amniotic fluid for testing. It can help determine whether your unborn baby has CMV.

Treatment

Is there a treatment for CMV?

For otherwise healthy people, CMV usually doesn't require treatment. If your immune system is weakened, your doctor may use one of several different medicines to treat CMV infection. However, because CMV is a virus, regular antibiotics won't work against it. Antiviral drugs are usually prescribed, which slows the virus down (but cannot cure CMV).

If you are pregnant and your baby has CMV, you doctor will likely check your baby once he or she is born for any problems or birth defects so they can be treated early. Treatable symptoms in newborns include pneumonia, hearing loss and inflammation of the eye.

Complications

What are the complications of CMV for pregnant women?

If a pregnant woman transmits CMV to her unborn baby, miscarriage, stillbirth or death of the newborn may occur. Newborns who survive are at an increased risk for hearing loss and mental retardation. However, only 1% of newborns who are infected with CMV during pregnancy experience problems from the virus. Most are born healthy, or with only mild CMV symptoms.

Other Organizations

Questions to Ask Your Doctor

  • I'm pregnant and have CMV. Do I need any special tests?
  • What treatment is best for me?
  • Are there any activities I should restrict while I'm sick?
  • How long should I keep my child home from school?
  • How long will I be contagious?
  • I have CMV. Should I stop breastfeeding my baby?
  • I work at a daycare center. How long should I stay home?
  • Will my newborn have any problems because I had CMV while I was pregnant?
  • I have HIV. Do I need any special treatments?
  • Should I see an eye doctor?

Source

Cytomegalovirus by GH Taylor, M.D. (American Family Physician February 01, 2003, http://www.aafp.org/afp/20030201/519.html)

2/14/03