Cytomegalovirus

The Cytomegalovirus is a herpes virus and mostly affects humans. The transfer from person to person takes place via a smear and droplet infection as well as by parenteral route. Symptoms do not appear in a healthy person. The body is infected for life.

What is the cytomegalovirus?

The cytomegalovirus is a common virus that can infect almost anyone. Around 80 percent of 30-year-olds in industrialized countries are carriers of this virus. It has double-stranded DNA and multiplies very slowly. Most infected people are symptom free and are unaware of the virus.

Only pregnant and immunocompromised people have cause for concern. Because this virus is a herpes virus, the body keeps this virus for life. It is only noticeable when the immune system is weakened by illness. Its host spectrum is limited to humans. It is spread through body fluids such as saliva, urine, semen and blood.

If the patient is pregnant and develops an active infection, she can transmit the virus to the fetus through the placenta. The infected human cells enlarge microscopically and are called owl eye cells. There are no curative drugs for the cytomegalovirus, only for the weakened immune system.

Meaning & function

Structurally, the cytomegalovirus is no different from other herpes viruses. In principle it can affect all organs, but mainly the ductal epithelial cells of the salivary glands. This is followed by the cells of the mammary glands, lungs and kidneys. The infected cells are enlarged under the microscope.

The cytoplasm contains protein aggregates. These are deposits of virus proteins that are produced in excess. Because the infected cells look like owl eyes, they are called owl eye cells. Herpes viruses persist in the host's body for a lifetime and are highly associated with the cells. In most cases, the host remains symptom-free even with the initial infection, but sheds the virus for a year. Existing or newly emerging immune-weakening diseases can lead to serious illnesses.

When reactivated, the virus is distributed in the body secretions such as urine, saliva, breast milk, semen and the cerfical fluid of the vagina. The mononuclear cells, i.e. all cells with a nucleus, carry the latent virus genome. The viral RNA transcriptases of the early genes can be detected in these cells. The progenitor cells in the bone marrow of the myeloid rheumatism may be the primary site of latency.

Once their offspring have been activated to diffuse in tissue macrophages, the virus can enter the replication cycle. This leads to the activation and reproduction of the virus. If the virus is contained in body fluids, it can be transmitted through close contact. Sexual intercourse, breastfeeding, blood transfusions, or organ transplants are possible routes of transmission. CMV infection is one of the most common infections after a kidney transplant. The cytomegalovirus can cross the placenta and infect the unborn child.

Dangers, disorders, risks & diseases

CMV is a virus that is widespread worldwide and can infect almost anyone. In most cases, healthy children and adults will have no symptoms. In rare cases, otherwise immune and healthy people become very ill.

These can develop into mononucleosis. Symptoms of these include a sore throat, swollen glands and tonsils, fatigue, and nausea. Other typical complaints are fever, unexplained elevated liver values ​​and possibly pneumonia. Intestinal complications such as diarrhea, fever and abdominal pain can also arise. A variety of neurological complications as a result of this viral infection in the nervous system have been observed.

This can be inflammation of the brain. The virus can cross the placenta and cause serious illness. Hepatomegaly and jaundice can occur. A general disability is not uncommon. In the worst case, newborns with a CMV infection can suffer hearing loss or eye malformations. The latter can develop into central vision loss, scarring of the retina, inflammation of the light-sensitive layer of the eye, or swelling.

Intellectual disability, lack of coordination, seizures, and even death can also occur. If there are already immune-weakening diseases, such as HIV, the symptoms are severe. The complications are much more severe and over a longer period of time. High fever, pneumonia, encephalitis, retinitis, esophagitis, pancreatitis, and hepatitis are possible. Encephalitis is often fatal. CMV can also have serious consequences for leukemia patients, tumor patients treated with cytostatics and transplant recipients. Blindness, transplant rejection, and colitis can be a possible complication.

The cytomegalovirus cannot be removed with medication, only the symptoms are alleviated. It persists in the body. The virus is not always in the active form. Only in the active form is it contained in body fluids and is highly contagious.