Cytomegalovirus

What is Cytomegalovirus (CMV)?

Human CMV is a common virus that infects most people some time during their lives, but rarely causes illness. It is a member of the herpes virus group and can be present in your body without causing illness; it can be reactivated later and cause illness.


Who gets CMV?

Anyone. Many adults may have been infected at some time during their life.


How is CMV spread?

CMV is spread from person to person by contact with urine, saliva, breast milk, blood, semen, and possibly other body fluids. The virus can spread from an infected mother to her fetus or newborn baby. CMV can also be spread by blood transfusion and organ transplants.


What are the symptoms of CMV infection?


Most children and adults infected with CMV do not have symptoms. Those who do may have fever, swollen glands, and feel tired. Immunocompromised people (such as AIDS patients or those receiving cancer treatments) may have a more serious illness such as pneumonia or inflammation of the eye. The most severe form of the disease occurs when a mother infects her fetus. Most of these infections are without symptoms, however, about 10% of these babies later have some type of disability such as hearing loss, learning disabilities, or mental retardation.

• CMV can affect the eyes causing blurred vision, loss of central vision and blindness - known as CMV retinitis.
• It can cause a fever, diarrhoea and stomach cramps - CMV colitis.
• The virus can cause mouth ulcers, pain in the mouth and throat and difficulty swallowing - CMV oesophagitis.
• CMV can affect the lungs and cause pneumonia-like symptoms - known as CMV pneumonitis.
• It can also cause confusion, memory loss, fever and lethargy - CMV encephalitis

How soon after infection do symptoms appear?

Information about this is not exact. Illness following transfusion with infected blood begins three to eight weeks after the transfusion. Infections acquired during birth may occur three to twelve weeks after delivery. The time frame for onset of symptoms following person to person transmission is unknown, since most people never become ill.


How long can an infected person carry CMV?

CMV may remain in the body throughout a person's lifetime. The virus may be found in the urine or saliva of infected people who may or may not be ill.


How is CMV diagnosed?


Diagnosis is made by finding the virus in the blood, urine, saliva, semen, breast milk, or other body fluids or tissues.

• CMV retinitis can be tested for by an eye examination.
• CMV oesophagitis and colitis can be detected by endoscopy or biopsy.
• CMV pneumonitis is usually diagnosed through bronchoscopy or biopsy. It is often only diagnosed after certain bacteria and PCP have been ruled out.
• CMV encaphilitis diagnosis often involves a lumbar puncture or spinal tap (for cerebrospinal fluid) and/or a brain MRI (magnetic resonance imaging) scan.

What is the treatment for CMV infections?

There is usually no treatment for CMV. However, patients with AIDS or cancer who have an eye infection may be treated with ganciclovir.


Should an infected person be excluded from school or work?

No.


What precautions should pregnant women take?

Pregnant women should be careful to wash their hands after changing nappies or having contact with urine or saliva. Those working in day care centers should not kiss babies or young children on the mouth. Pregnant women should ask their midwife/doctor about CMV infections.


What can be done to stop the spread of CMV?

Good handwashing is the best way to prevent infection with CMV. Health care workers should wear disposable gloves when handling sheets or clothes soiled with faeces or urine.


References

http://health.utah.gov/els/index.html