Cytomegalovirus (CMV)What Is It?
Cytomegalovirus is related to the herpes virus. It is so common that almost all adults in developing countries and 50% to 85% of adults in the United States have been infected.
Usually cytomegalovirus is a mild disease that does not cause any serious problems in healthy children and adults. Most people get flu-like symptoms or an illness similar to mononucleosis, if they develop symptoms at all.
However, being infected with this virus can be serious and even fatal in some people, including:
- People receiving chemotherapy for cancer
- Adults with diseases that suppress the immune system, such as AIDS
- People who have received organ or bone marrow transplants
- Newborn babies of women infected with the virus during pregnancy
Women infected with cytomegalovirus for the first time during pregnancy can pass the virus to their unborn babies. The virus can pass from mother to baby in vaginal secretions during delivery and in breast milk after birth. The virus can pass from person to person in saliva, urine, semen and blood. It can contaminate blood transfusions and transplanted organs. Some people, such as those who have had a bone marrow transplant, are at high risk of developing complications if they become infected with this virus. If these people need blood transfusions, they get specially prepared blood products to decrease the risk of becoming infected.
Symptoms
There are three classes of cytomegalovirus infection, each with different symptoms:
Congenital
Up to 40% of babies born to women who become infected with cytomegalovirus during pregnancy will become infected, although not all the babies will have symptoms at birth. This type of cytomegalovirus is the second most common and identifiable cause of mental retardation after Down syndrome.
Newborns with cytomegalovirus are likely to be born premature and at a low birth weight. Other problems include a small brain (microcephaly) or other problems of the nervous system that can cause deafness, mental retardation or death. This infection can cause the liver and spleen to become larger than normal, yellow skin (jaundice) and eyes from liver disease), and blood disorders. The most common blood disorder is a low number of platelets, the cells that help the blood to clot. Newborns with cytomegalovirus can have a rash that consists of small bruises called petechiae and larger bruises known as purpura.
A baby born to a mother who was infected with the virus before she became pregnant is less likely to be born with CMV. Only 0.5% to 1.5% of such babies are infected, and their problems tend to be less severe than those of babies born to mothers infected during pregnancy. Babies infected during birth or through breastfeeding also have less serious problems. Of these babies, approximately one in five will develop some degree of hearing loss.
Healthy people
In most cases, healthy people who become infected with cytomegalovirus during young adulthood usually develop minor symptoms or no symptoms at all. When symptoms occur, they are similar to the symptoms of mononucleosis:
- Fatigue
- Low-grade fever
- Muscle aches
- Decreased appetite
- Enlarged lymph nodes
- Sore throat
The virus usually becomes inactive in healthy people.
Immune-suppressed people
People who have had an organ transplant and those with AIDS can develop serious illness caused by cytomegalovirus. Typically, the inactive virus from a previous infection, perhaps from decades ear, becomes active again because the person's immune system is weakened.
The reactivated cytomegalovirus becomes an active infection that can affect the lungs, esophagus, stomach, intestines, eyes, nervous system and brain. A condition called cytomegalovirus retinitis affects the eye and can cause blindness. Pneumonia caused by cytomegalovirus can be life threatening. Cytomegalovirus can affect any part of the gastrointestinal tract, including the esophagus, stomach, liver, pancreas and colon, causing ulcers, hepatitis, intestinal obstruction and colitis. Symptoms include painful and difficult swallowing, nausea, vomiting, abdominal pain, yellow skin and watery or bloody diarrhea.
People with weakened immune systems are at greater risk of getting very ill if they become infected for the first time with cytomegalovirus.
Diagnosis
Doctors may order a blood test, called the TORCH test, for newborns with low birth weight, jaundice, small brains or other problems associated with cytomegalovirus. The test can be inaccurate, however. The diagnosis is confirmed by testing blood or tissue from the infant within three weeks of birth.
Young, healthy adults usually do not need to be tested because they do not need to be treated. They usually recover over a period of weeks. In some instances, blood tests may be done to check for mononucleosis and liver inflammation. Occasionally, ultrasound testing is needed to monitor the liver or spleen. Routine testing of pregnant women for cytomegalovirus is not recommended at this time, according to the U.S. Centers for Disease Control and Prevention (CDC).
People with HIV/AIDS have a higher risk of developing cytomegalovirus retinitis if they have severely weakened immune systems. For this reason, they undergo routine eye examinations to check for the presence of the virus, so that it can be identified early.
Expected Duration
If you have a healthy immune system, you can expect the virus to remain inactive throughout your life. You will not have symptoms related to cytomegalovirus.
A person with a weakened immune system will often need lengthy treatment. Improving the immune system is the best hope for combating any invading viruses.
Prevention
Pregnant women who care for young children should wash their hands after contact with the saliva, urine, stool or any other secretions of a child and after changing diapers. Breastfeeding is recommended, even in women known to be infected, because the benefits of breastfeeding are thought to outweigh the risks of transmitting the disease to the baby, according to the CDC.
The best way for a healthy adult to avoid getting the disease is to follow the same precautions recommended for protecting against all sexually transmitted diseases.
People who get a transplanted organ may need to take medication to prevent infection with cytomegalovirus in some instances. Testing the blood supply for the virus has reduced transmission of the disease. If people with weakened immune systems need blood transfusions, they will probably receive blood that has had the white blood cells removed. This lowers the risk of transmission.
Also, it is essential for people with HIV/AIDS who have weakened immune systems to schedule regular eye exams to detect cytomegalovirus early, even before symptoms develop. This can help to avoid the loss of vision.
Treatment
Healthy people generally do not need any treatment for cytomegalovirus.
Although there is no cure for cytomegalovirus, organ transplant recipients, people with AIDS and others with immune disorders may need treatment to suppress the infection. Treatment may be directed at the underlying immune disorder. Recent experience in treating people with AIDS shows that when a person's immune system improves, cytomegalovirus can improve or go away, especially if the count of T-cells (helper immune cells) rises above 100.
Drugs commonly used to treat cytomegalovirus include ganciclovir (Cytovene) and foscarnet (Foscavir). Ganciclovir can be given intravenously (into a vein), orally or as a pellet implanted in the eye to treat an infection in the retina. Foscarnet must be given intravenously. Side effects of ganciclovir include the suppression of white blood cells (needed to fight infection), red blood cells (that carry oxygen) and platelets (that help the blood to clot). Because foscarnet can cause kidney damage, kidney function needs to be monitored carefully.
When To Call A Professional
A doctor should see your baby if he or she has yellow skin (jaundice), hearing problems, rash, fever or vomiting. If you are a healthy adult, call your doctor if you have abdominal pain, vomiting or fevers that last longer than 48 hours or if you have significant fatigue.
If you have a weakened immune system, see a doctor if you have visual disturbances, mental changes, difficulty or pain swallowing, abdominal pain, vomiting or diarrhea, cough or difficulty breathing.
Prognosis
In healthy people, cytomegalovirus is mild and goes away on its own. In babies, consequences can last a lifetime or be fatal. People with weakened immune systems can lose their vision or have life-threatening and disabling illnesses that can require lifelong therapy.
Additional Info
American Academy of Family Physicians (AAFP)
11400 Tomahawk Creek Parkway
Leawood, KS 66211-2672
Phone: 913-906-6000
Toll-Free: 1-800-274-2237
Email: email@familydoctor.org
http://www.familydoctor.org/
CDC National Prevention Information Network (NPIN)
National Center for HIV, STD and TB Prevention
P.O. Box 6003
Rockville, MD 20849-6003
Toll-Free: 1-800-458-5231
Fax: 1-888-282-7681
TTY: 1-800-243-7012
Email: info@cdcnpin.org
http://www.cdcnpin.org/
Centers for Disease Control and Prevention (CDC)
1600 Clifton Road
Atlanta, GA 30333
Phone: 404-639-3534
Toll-Free: 1-800-311-3435
http://www.cdc.gov/
