Cytomegalovirus (CMV)

Cytomegalovirus (CMV) is a type of herpes virus that can sometimes make you sick. Almost everyone gets it at some point in their lives, but most people have mild or no symptoms. CMV can cause serious complications if you have a weakened immune system. Organ and stem cell transplant recipients are at an especially high risk.

If you’re pregnant and have CMV, your baby can be born with congenital CMV. Congenital CMV can cause vision or hearing loss and developmental delays. About 1 in 200 babies is born with CMV each year. About 1 in 10 have symptoms at birth.

Symptoms of cytomegalovirus infection

Most people don’t have symptoms of CMV. If you do, they could include:

• Extreme tiredness (fatigue)
• Muscle aches
• Sweating
• Headache
• Sore throat
• Swollen lymph nodes
• Rash

Cytomegalovirus infection causes

A type of herpes virus, human herpesvirus-5 (HHV-5), causes CMV infections. If you’ve had CMV in the past, the virus can stay in your body, inactive. When your immune system is weakened, it can reactivate and cause you to get sick. While most people can fight off CMV without symptoms, a new or reactivated infection can cause serious complications in someone with a weakened immune system.

How do you get CMV?

You get CMV from the body fluids of someone else who’s infected. This includes spit (saliva), pee (urine), blood, breast milk and semen. It can spread through:

• Direct contact with pee and spit
• Sex
• Vertical transmission (from a pregnant woman to the fetus)
• Breastfeeding
• A blood transfusion or organ transplant

Risk factors

You’re at higher risk for cytomegalovirus if you:

• Have received an organ or stem cell transplant
• Are under the age of 5 (about 1 in 3 people get infected by age 5)
• Work with or live with children under the age of 5
• Have a compromised immune system
• Live in close contact with many other people

Complications

Serious complications from CMV are rare. You’re most likely to experience life-threatening health issues if you have a weakened immune system, especially if you’ve received an organ or stem cell transplant. Complications could include:

• Brain swelling (encephalitis)
• Eye damage (CMV retinitis)
• Inflammation in your digestive tract (gastritis or colitis)
• Lasting cognitive issues, including trouble focusing, remembering and problem-solving
• Lung inflammation (pneumonitis)
• Miscarriage or stillbirth
• Pneumonia
• Recurrent fevers and tiredness
• Rejection of donor organ
• Tear or hole in your esophagus or intestines

Babies born with CMV can have lasting health conditions, including hearing or vision loss and developmental differences. Hearing loss can develop later, even if your child didn’t have symptoms of CMV at birth. Infants with severe symptoms may have life-threatening complications of CMV.

How doctors diagnose cytomegalovirus

Healthcare providers use blood, pee or spit (saliva) tests to diagnose CMV. As it usually causes mild symptoms, most people won’t need to be tested.

Your healthcare provider may test you for CMV if you have a weakened immune system. Your child’s healthcare provider may test them in their first few weeks of life if they have symptoms of congenital CMV.

How is cytomegalovirus treated?

Healthcare providers treat CMV with the antiviral medications ganciclovir (GCV) or valganciclovir (VGC). But you usually only need treatment if you have a compromised immune system. Providers also treat babies born with symptoms of CMV. 

Antiviral medications can lessen the risk of health problems in babies born with CMV, but they may not completely prevent them. Speech and occupational therapy can help manage the effects of hearing loss and developmental issues in congenital CMV.

When should I see my healthcare provider?

Contact your provider right away if you have symptoms of CMV and have a weakened immune system, or if you think your baby has symptoms of congenital CMV. Talk to your healthcare provider about steps you can take to prevent CMV if you:

• Have a compromised immune system
• Have or will have a stem cell or organ transplant
• Are pregnant or plan to become pregnant

What can I expect if I have CMV?

What to expect depends on many factors. Your provider can help you know what to expect in your specific situation.

Most people don’t have symptoms of CMV. If you do, you may need to rest and take breaks more often than you usually would. Symptoms can last anywhere from a week to several months.

If you have a weakened immune system, you’ll likely need to be hospitalized for treatment and monitoring. Early treatment gives you the best chance of a full recovery.

If your child was diagnosed with CMV at birth, you’ll work closely with their care team to try to reduce the risk of lasting health effects. Some conditions, like hearing loss, can develop later in childhood.

How long does it take for CMV to go away?

Symptoms of CMV can last for a long time. You may feel run down, tired or weak for several weeks or months.

Once infected, CMV can stay in your body, inactive, for the rest of your life. If you have a weakened immune system, it can reactivate and cause serious symptoms or organ damage.

Can you prevent cytomegalovirus?

You can reduce your risk of CMV by avoiding contact with other people’s body fluids. Specific ways to reduce your risk include:

• Don’t share food, cups or eating utensils.
• Don’t put a child’s pacifier in your mouth.
• Wash your hands after going to the bathroom, changing a diaper or helping a child go to the bathroom. Use warm water and soap.
• Use a condom when having oral, anal or vaginal sex, even if you always have sex with the same partner.

If you’ve received an organ transplant, your provider may treat you with antiviral medications to prevent CMV. They may monitor your blood so they can treat you as soon as possible if you do get an infection.