Cytomegalovirus (CMV) is distributed worldwide. Many people become infected unnoticed in the course of their lives. But once acquired, the pathogen remains in the body and can be a danger: in an immune deficiency for the person concerned, in a pregnancy for the unborn child. The CMV belongs to the large group of herpesviruses, which can cause not only the familiar cold sores, but also chickenpox, shingles and the Pfeiffer glandular fever.
Virus remains in the body for life
What they all have in common is that they stay in the body for life, usually without being noticeable. Only when the immune system is weakened, they come to life again. This can be caused by stress and fever (for example, cold sores), but also serious infections, cancer or organ transplants. Then the viruses are particularly dangerous because they can cause serious diseases.
Distribution of cytomegaloviruses
It is estimated that 50 to 80 percent of adults are infected with the virus. Thus, the risk of infection, hard to ban. This is all the more so as most people do not know that they carry the CMV in them, as the initial infection usually goes unnoticed or manifests itself only in mild flu-like symptoms.
The pathogens are found in body fluids such as saliva, blood, urine, sperm or the mucus of the cervix - their transmission through the skin and mucous membranes as a result of lubrication or droplet infection. The unborn child can become infected via the placenta, the baby through breast milk while breastfeeding. The latter is problematic in premature babies, as the virus may still cause brain damage in these.
Symptoms of cytomegalovirus
In most cases, the initial infection is unproblematic with little or no symptoms. However, if immunocompromised people become infected or if they reactivate the already lurking virus, life-threatening clinical pictures can occur. Therefore, if suspected, a blood test must be carried out, by means of which the virus can be detected early and therapy can be initiated.
If this does not happen, it comes after a few days, first to exhaustion, fever, muscle and joint pain similar to a flu. In the further course, various organ systems can be attacked by the virus - typically, for example, inflammations of the lung, the heart muscle, the kidneys, the liver, the brain and the retina (retinitis). The bone marrow can also be affected, which can lead to disorders of the blood cell production and thus to a further weakening of the immune defense and increased risk of infection, for example by fungi.
In about one-third of cases when women first become infected with CMV during pregnancy, the virus is transmitted to the unborn child. The symptoms vary from enlargement of the liver and spleen to life-threatening illnesses. Complications may include hearing loss, vision loss, and mental retardation. If the pregnant women were previously infected, the rate of infection transmission to the child is only one percent, and as a rule no symptoms or disturbances are to be feared.
Diagnosis of cytomegalovirus
The detection of CMV infection is carried out by means of various blood tests. Thus, on the one hand, the virus can be detected directly quantitatively. It determines how high the "viral load" is, ie how many viruses are in the body. This procedure is important to check if a drug is effective. On the other hand, the infection can be detected indirectly by the presence of certain antibodies. The latter also indicate whether the infection is acute or has been a long time ago.
Prevention and therapy of cytomegalovirus
Patients with weakened immune systems must be protected from CMV infection or reactivation. Those affected include:
- Cancer patients especially under chemo
- Transplant recipients. CMV infection is one of the most common complications of transplantation, especially retinitis is a common complication in HIV patients.
For efficient prophylaxis, it is initially estimated how high the individual risk is and the treatment or controls are adjusted accordingly. If it is high, those affected receive a virus-inhibiting agent (antiviral agent), before the virus can even multiply in the blood. If it is lower, they are regularly monitored by means of a blood test and - if the virus is increased - therapeutic measures may be taken before symptoms appear. Depending on the case, there are the drugs in the form of infusions or tablets or capsules.