Cytomegalovirus is a herpes virus and largely affects humans. It is transferred from person to person by smear and droplet infection as well as by parenteral routes. No symptoms occur in a healthy person. The body is infected for life.
What is cytomegalovirus?
Cytomegalovirus is a common virus that can infect almost anyone. About 80 percent of 30-year-olds in industrialized countries are carriers of this virus. It has double-stranded DNA and replicates very slowly. Most infected people are asymptomatic and unaware of the virus. Only pregnant and immunocompromised individuals have a reason to be concerned. Since this virus is a herpes virus, the body retains it for life. It only becomes noticeable when the immune system is weakened by illness. Its host range is limited to humans. It spreads 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 via the placenta. The infected human cells enlarge microscopically and are called owl eye cells. No curative drugs exist for cytomegalovirus, only for the weakened immune system.
Significance and function
Structurally, cytomegalovirus is no different from other herpes viruses. It can infect basically 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. Under the microscope, the infected cells are magnified. The cytoplasm contains protein aggregates. These are deposits of viral proteins produced in excess. Because the infected cells look like owl’s eyes, they are called owl’s eye cells. Herpes viruses persist in the host’s body for life and are highly associated with the cells. In most cases, the host itself remains asymptomatic during the initial infection, but excretes the virus for a year. Pre-existing, or newly emerging immunocompromising diseases can lead to serious illness. During reactivation, the virus is distributed in body secretions such as urine, saliva, breast milk, semen, and the cerfical fluid of the vagina. The mononuclear cells, all cells with a nucleus, carry the latent viral 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 rheum may be the primary site of latency. Once their progeny have been activated to diffuse into tissue macrophages, the virus can enter the replication cycle. This leads to activation and replication of the virus. If the virus is present in body fluids, it can be transmitted during 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 kidney transplantation. Cytomegalovirus can cross the placenta and infect the unborn child.
Hazards, disorders, risks, and diseases
CMV is a worldwide and widely distributed virus that can infect almost anyone. In most cases, healthy children and adults have no symptoms. In rare cases, otherwise immune-competent and healthy individuals become very ill. These can develop mononucleosis. Symptoms of this include sore throat, swollen glands and tonsils, fatigue and nausea. Other typical symptoms include fever, unclear elevated liver enzymes, and possibly pneumonia. Intestinal complications, such as diarrhea, fever, and abdominal pain, may also develop. A variety of neurological complications as a result of this viral infection in the nervous system have been observed. These may include inflammation of the brain. The virus can cross the placenta and cause serious illness. Hepatomegaly and jaundice may occur. General disability is not uncommon. In the worst cases, newborns with CMV infection may suffer hearing loss, or malformation of the eyes. The latter may develop into central vision loss, scarring of the retina, inflammation of the light-sensitive layer of the eye, or swelling. Mental retardation, lack of coordination, seizures, and even death may also occur.With already existing immunocompromising 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. ZMV 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. Cytomegalovirus cannot be removed with medication, only symptoms alleviated. It persists in the body. The virus is not always in the active form. Only in the active form is it present in body fluids and highly contagious.
