Cytomegalovirus (CMV)

Cytomegalovirus (CMV) is a member of the herpes family. Related viruses include Epstein-Barr (causes glandular fever), varicella-zoster (causes chicken pox) and herpes simplex (causes cold sores). This viral infection can be spread through coughing, contact with blood, urine or faeces, or via the mucous membranes, such as the mouth and genitals.

In Australia, about 50 per cent of young adults have been infected. In healthy people, CMV infection causes nothing more than a flu-like illness that lasts a few days. In certain people, however, including transplant patients and pregnant women, the effects can be much more serious.

Many organs can be targeted

CMV can infect virtually any organ of the human body. The most common organs include the blood, brain, colon, eye, heart, kidney, liver, lung and stomach. In the case of an organ transplant patient, the symptoms of CMV can be easily confused with rejection.

Symptoms may vary depending on which organ is affected, but generally a person with CMV will experience lethargy, a high temperature and a drop in white blood cell levels. For most people, a CMV infection poses no real health threat. The symptoms are generally mild and flu-like, although some may feel unwell for a few weeks, rather than a few days. Some people experience no symptoms.

CMV infection is permanent

Once a person has contracted CMV, they will carry it for life. This is because the virus lies dormant inside the body and may or may not reactivate itself at any time.

Pregnant women

Women can catch CMV during pregnancy and pass it on to their baby – this is called congenital CMV. Around one in ten infected babies will have lasting problems. These can include deafness, poor eyesight, intellectual disability, an enlarged liver or spleen, and a small head.

Pregnant women should wash their hands after handling bodily secretions from babies or children, for example, after changing nappies or wiping noses.

Organ transplant patients

People with compromised immune systems, such as people receiving organ transplants, and people receiving treatment for HIV/AIDS or cancer are at increased risk of serious complications of CMV.

The drugs that suppress transplant rejection also reduce the ability of the immune system to fight viruses, so a CMV infection can be much more serious. For example, infection of the brain, called CMV encephalitis, may lead to convulsions and coma. Organ donors are tested and where possible donations from CMV seropositive donors avoided when the recipient is CMV seronegative.

Treatment for CMV

Treatment depends on the severity of the condition. In a healthy person, bed rest, drinking plenty of fluids and medical supervision are all that is generally required. Pregnant women and patients with suppressed immunity need careful medical monitoring and frequent testing, including blood, sputum and urine tests. Antiviral medication may be prescribed.

Where to get help

• Your GP (doctor)
• Immunologist or infectious disease physician (your doctor will refer you)