Cytomegalovirus (CMV) (cont.)

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What are the risk factors for cytomegalovirus infection?

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Those at risk for CMV include young children and adults who work closely with them, people who undergo blood transfusions, people who have multiple sex partners, and people who have received a CMV-infected mismatched organ or bone marrow transplant. People at risk for complications from CMV infection include pregnant women and those with a weakened immune system, such as people infected with HIV, individuals who have undergone organ transplantation, cancer patients, or those who are taking medications that might suppress their immune system.

Is CMV contagious?

CMV is contagious to individuals who have not been infected with it previously, but it is not especially easy to get infected.

How long is cytomegalovirus contagious?

The contagious period when virus is being shed in body fluids may last for months in an infected individual, and virus may be shed without symptoms at intermittent periods throughout life.

How is cytomegalovirus transmitted?

Infection with CMV is relatively common, but CMV does not spread very easily or through casual contact. Transmission requires direct contact with body fluids (such as saliva, urine, blood, semen, vaginal secretions, or breast milk) from an infected person. People become infected with CMV through kissing, breastfeeding, sexual contact, blood transfusions, injection drug use (sharing needles), or organ and bone marrow transplantation. CMV can be shed in body fluids for months and intermittently for life, especially in people with compromised immunity such as HIV disease, and it may not cause any symptoms. CMV transmission can also occur during pregnancy through the placenta, or from vaginal secretions at delivery. This may cause congenital CMV infection in the newborn. Approximately 1%-4% of women who have never been infected with CMV will have their primary (first) infection during pregnancy. The virus can cross the placenta and infect the fetus through the blood. Approximately one-third of women who become infected for the first time during pregnancy will pass the infection to the baby.

Breastfeeding can transmit CMV to the baby after birth, but there is no need to avoid breastfeeding unless the baby is premature and the doctor recommends avoiding it. Freezing and pasteurization of breast milk can lower the risk of transmission but does not eliminate it.

What is the incubation period for cytomegalovirus?

The incubation period between the time of getting the virus and the time that symptoms develop ranges from three to 12 weeks in cases of documented CMV infection after a transfusion of infected blood. CMV is usually benign; and there is no public health or medical reason to screen for it routinely. In addition, it may be shed intermittently for a very long time. This makes it difficult to say what the incubation period may be with the commoner forms of transmission, such as contact with saliva, urine, and genital fluids.

What are cytomegalovirus infection symptoms and signs?

Most people infected with CMV do not have any symptoms or complications and do not recall any contact with an infected person, so most people are unaware they have been infected. Acute CMV infection may cause infectious mononucleosis-like (or mono-like) symptoms, such as fever, enlarged lymph nodes, sore throat, muscle aches, loss of appetite, enlarged liver or spleen, and fatigue.

In people with suppressed immune systems, CMV infection can attack different organs of the body and may cause blurred vision and blindness (CMV retinitis), lung infection (pneumonia), diarrhea (colitis), inflammation of the liver (hepatitis), or inflammation of the brain (encephalitis), which may cause behavioral changes, seizures, or coma.

Infants with CMV infection at birth (congenital CMV) can show signs and symptoms of yellow skin and eyes (jaundice), skin rash, low birth weight, pneumonia, enlarged liver and spleen, and seizures.

Medically Reviewed by a Doctor on 12/1/2015

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Cytomegalovirus (CMV) Infection - Symptoms Question: What symptoms and signs did you experience with CMV?
Cytomegalovirus (CMV) Infection - Prevention Question: Please share tips and suggestions for preventing CMV.
Cytomegalovirus - Risk Factors Question: If you have HIV, please share your experience with CMV.
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