Name: cmv transmission and reactivation
Uploaded: 2026-03-12T13:36:04.000Z
Duration: 1 min 27 s
Channel: JoVE

Cytomegalovirus disease is caused by infection with a herpesvirus belonging to the genus Cytomegalovirus.In humans, the virus can spread through infected body fluids, such as during blood transfusion, organ transplant, sexual contact, or from mother to fetus.Once inside the body, the virus establishes latency primarily in monocytes and hematopoietic progenitor cells.During active infection, it interferes with MHC class I antigen presentation, preventing CD8&#8314; T cells from recognizing and eliminating infected cells.Some viral proteins attach to host chemokines, hindering the recruitment of immune cells to the infection site.Together, these mechanisms allow the virus to persist within host cells.When a person's immunity is weakened, such as after an organ transplant, the virus may become active again.It takes over the host cell to produce and release new virions, spreading the infection.Virus-infected cells, especially in epithelial tissues, become enlarged and develop characteristic intranuclear inclusion bodies, which are visible under a microscope.

cytomegalovirus disease

Cytomegalovirus Disease

Cytomegalovirus (CMV) disease is caused by human cytomegalovirus, a double-stranded DNA virus of the Herpesviridae family. While primary CMV infection is often asymptomatic in immunocompetent individuals, the virus can cause severe disease in neonates and immunocompromised patients. CMV is the most common cause of congenital viral infection in the United States, and a major pathogen in solid organ and hematopoietic stem cell transplant recipients.CMV is transmitted via bodily fluids, sexual contact, organ transplantation, blood transfusions, and vertically from mother to fetus. After primary infection, the virus establishes lifelong latency, primarily in monocytes and progenitor cells, and may reactivate during periods of weakened cell-mediated immunity. Reactivation can occur spontaneously or following immunosuppressive therapy, particularly in transplant recipients, leading to systemic infection.In congenital CMV disease, the virus crosses the placenta during maternal viremia, especially in primary infections during the first trimester. The resulting fetal infection may lead to jaundice, petechiae, hepatosplenomegaly, microcephaly, hearing loss, and periventricular calcifications. In adults, reactivation may cause pneumonia, retinitis, colitis, or encephalitis in immunosuppressed patients, while immunocompetent individuals may develop a mononucleosis-like illness that is heterophile-antibody negative.CMV evades immune surveillance through multiple mechanisms. It interferes with MHC class I antigen presentation, preventing CD8&#8314; T cell-mediated cytolysis, and secretes proteins that bind host chemokines, impairing immune cell recruitment. Additionally, CMV microRNAs suppress translation of MHC-related proteins, further inhibiting immune recognition.Diagnosis of CMV disease relies on serologic assays (including IgM and IgG avidity) and molecular tests such as PCR for viral load assessment. Antiviral agents like ganciclovir, valganciclovir, foscarnet, and cidofovir are used for treatment, particularly in high-risk populations. No vaccine is currently available, although several candidates are under investigation.

Cytomegalovirus (CMV) disease is caused by human cytomegalovirus, a double-stranded DNA virus of the Herpesviridae family. While primary CMV infection is ...

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cmv transmission and reactivation

Cytomegalovirus (CMV) is a human double-stranded DNA virus in the Herpesviridae family. CMV disease can be mild or silent in many healthy people, but it can cause serious illness in newborns and in people with weakened immune systems. It is also a major cause of congenital viral infection in the United States and a common problem in solid organ and hematopoietic stem cell transplant recipients.

CMV spreads through bodily fluids, sexual contact, organ transplantation, blood transfusions, and from mother to fetus during pregnancy. After the first infection, the virus stays in the body in a latent state, mainly in monocytes and progenitor cells. When cell-mediated immunity drops, CMV can reactivate on its own or after immunosuppressive therapy. This is especially important in transplant patients, where reactivation can lead to systemic infection.

In congenital CMV disease, the virus can cross the placenta during maternal viremia, especially when the mother has a primary infection in the first trimester. Fetal infection may cause jaundice, petechiae, hepatosplenomegaly, microcephaly, hearing loss, and periventricular calcifications. In adults with weakened immunity, reactivation may cause pneumonia, retinitis, colitis, or encephalitis. People with normal immune systems may develop a mononucleosis-like illness that is heterophile-antibody negative.

CMV evades immune detection in several ways. It interferes with MHC class I antigen presentation, which helps block CD8⁺ T cell-mediated killing. It also releases proteins that bind host chemokines, which reduces immune cell recruitment, and its microRNAs suppress translation of MHC-related proteins. Diagnosis uses serologic tests such as IgM and IgG avidity, along with PCR to measure viral load. Treatment may include ganciclovir, valganciclovir, foscarnet, or cidofovir, especially in high-risk patients. No vaccine is available yet, although several candidates are being studied.

CMV Transmission and Reactivation

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Cytomegalovirus (CMV) is a human double-stranded DNA virus in the Herpesviridae family. CMV disease can be mild or silent in many healthy people, but it can cause serious illness in newborns and in people with weakened immune systems. It is also a major cause of congenital viral infection in the United States and a common problem in solid organ and hematopoietic stem cell transplant recipients. CMV spreads through bodily fluids, sexual contact, organ transplantation, blood transfusions, and...

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key terms and concepts

Learn how cytomegalovirus spreads, stays latent, reactivates, and causes disease in newborns and immunocompromised patients. Includes diagnosis and treatment.

CMV Transmission and Reactivation | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

CMV Transmission and Reactivation

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