Human cytomegalovirus: Difference between revisions

From WikiMD's Wellness Encyclopedia

CSV import
 
CSV import
 
(One intermediate revision by the same user not shown)
Line 1: Line 1:
{{DISPLAYTITLE:Human Cytomegalovirus}}
{{SI}}  
 
{{Infobox medical condition
[[File:Cytomegalovirus_01.jpg|Cytomegalovirus virion|thumb|right]]
| name                    = Human cytomegalovirus
 
| image                  = [[File:Cytomegalovirus_01.jpg|left|thumb|Cytomegalovirus]]
'''Human cytomegalovirus''' (HCMV), also known as '''human herpesvirus 5''' (HHV-5), is a member of the [[Herpesviridae]] family, which includes other viruses such as [[herpes simplex virus]] and [[varicella-zoster virus]]. HCMV is a common virus that infects people of all ages and is typically asymptomatic in healthy individuals. However, it can cause significant disease in immunocompromised individuals and is a major cause of congenital infections.
| caption                = Electron micrograph of a human cytomegalovirus virion
 
| field                  = [[Virology]]
| synonyms                = HCMV, Human herpesvirus 5 (HHV-5)
| symptoms                = [[Fever]], [[sore throat]], [[fatigue]], [[swollen glands]]
| complications          = [[Congenital cytomegalovirus infection]], [[hearing loss]], [[vision loss]], [[neurological damage]]
| onset                  = Varies; congenital or acquired
| duration                = Lifelong latent infection
| causes                  = [[Cytomegalovirus]] infection
| risks                  = [[Immunocompromised]] individuals, [[pregnancy]]
| diagnosis              = [[Serology]], [[PCR]], [[viral culture]]
| differential            = [[Mononucleosis]], [[toxoplasmosis]], [[rubella]]
| prevention              = [[Good hygiene]], [[safe sex]], [[screening blood products]]
| treatment              = [[Antiviral drugs]] such as [[ganciclovir]], [[valganciclovir]], [[foscarnet]], [[cidofovir]]
| medication              = [[Ganciclovir]], [[valganciclovir]]
| frequency              = Common; 50-80% of adults infected by age 40
| deaths                  = Rare in healthy individuals; higher in immunocompromised
}}
{{Short description|Virus of the family Herpesviridae}}
'''Human cytomegalovirus''' ('''HCMV'''), also known as '''human herpesvirus 5''' ('''HHV-5'''), is a member of the [[Herpesviridae]] family of viruses. It is a common virus that infects people of all ages and is often asymptomatic in healthy individuals. However, it can cause significant disease in immunocompromised individuals and is a major cause of congenital infections.
==Virology==
==Virology==
[[File:CMVschema.svg|Schematic of CMV structure|thumb|left]]
HCMV is a large, enveloped virus with a double-stranded DNA genome. It is classified as a [[betaherpesvirus]], which is characterized by a slow replication cycle and the ability to establish lifelong latency in the host. The virus can reactivate from latency, particularly in individuals with weakened immune systems.
HCMV is an enveloped virus with a double-stranded DNA genome. The virus is characterized by its large size and complex structure, which includes a capsid, tegument, and lipid envelope. The genome of HCMV is approximately 230 kilobases in length and encodes for a variety of proteins that facilitate viral replication and immune evasion.
The HCMV genome is approximately 230 kilobase pairs in length and encodes for a variety of proteins that help the virus evade the host immune response and establish infection.
 
===Replication Cycle===
The replication cycle of HCMV begins with the attachment of the virus to the host cell surface, followed by entry into the cell. Once inside, the viral DNA is transported to the nucleus where it is transcribed and replicated. The virus assembles in the nucleus and acquires its envelope by budding through the nuclear membrane. Mature virions are then released from the cell to infect new cells.
 
==Pathogenesis==
==Pathogenesis==
HCMV can establish both lytic and latent infections. During lytic infection, the virus actively replicates and can cause cell death. In latent infection, the virus persists in a dormant state within the host cells, particularly in [[monocytes]] and [[macrophages]]. Reactivation of the virus can occur under conditions of immunosuppression.
HCMV is transmitted through bodily fluids such as saliva, urine, blood, and breast milk. Once inside the host, the virus can infect a wide range of cell types, including epithelial cells, endothelial cells, fibroblasts, and leukocytes.  
 
In healthy individuals, HCMV infection is usually asymptomatic or may cause mild flu-like symptoms. However, in immunocompromised individuals, such as those with [[HIV/AIDS]], organ transplant recipients, or patients undergoing chemotherapy, HCMV can cause severe disease, including pneumonia, retinitis, and gastrointestinal disease.
===Congenital Infection===
==Congenital Infection==
[[File:CMV_placentitis2_mini.jpg|CMV placentitis|thumb|right]]
[[File:CMV_placentitis2_mini.jpg|CMV placentitis|left|thumb]]
Congenital HCMV infection occurs when the virus is transmitted from a pregnant mother to her fetus. This can lead to a range of outcomes, from asymptomatic infection to severe disease, including [[hearing loss]], [[microcephaly]], and developmental delays. HCMV is the leading infectious cause of congenital disabilities in developed countries.
HCMV is the most common cause of congenital viral infection, affecting approximately 0.5% to 2% of all live births. Congenital HCMV infection can lead to a range of outcomes, from asymptomatic infection to severe disease with long-term sequelae such as hearing loss, developmental delay, and microcephaly.
 
The risk of congenital infection is highest when a primary maternal infection occurs during pregnancy. The virus can cross the placenta and infect the fetus, leading to placental inflammation and fetal damage.
==Clinical Manifestations==
In healthy individuals, HCMV infection is often asymptomatic or may present with mild flu-like symptoms. In contrast, immunocompromised individuals, such as those with [[HIV/AIDS]] or organ transplant recipients, can experience severe complications, including [[pneumonia]], [[retinitis]], and [[gastroenteritis]].
 
==Diagnosis==
==Diagnosis==
Diagnosis of HCMV infection can be achieved through serological tests, which detect antibodies against the virus, or through molecular techniques such as [[polymerase chain reaction]] (PCR) to detect viral DNA in blood or other body fluids.
Diagnosis of HCMV infection can be achieved through serological tests that detect antibodies against the virus, as well as molecular techniques such as PCR to detect viral DNA in blood or other body fluids. In congenital infections, diagnosis may involve testing the newborn's urine or saliva for the presence of the virus.
 
==Treatment==
==Treatment==
[[File:hcmvdrugs.pdf|Antiviral drugs for HCMV|thumb|left]]
[[File:CMVschema.svg|CMV replication cycle|left|thumb]]
Antiviral medications, such as [[ganciclovir]], [[valganciclovir]], [[foscarnet]], and [[cidofovir]], are used to treat HCMV infections, particularly in immunocompromised patients. These drugs inhibit viral DNA synthesis, thereby reducing viral replication.
Antiviral drugs such as [[ganciclovir]], [[valganciclovir]], [[foscarnet]], and [[cidofovir]] are used to treat HCMV infections, particularly in immunocompromised patients. These drugs inhibit viral DNA synthesis, thereby reducing viral replication.
 
[[File:hcmvdrugs.pdf|Antiviral drugs for HCMV|left|thumb]]
Treatment of congenital HCMV infection is more challenging, and the use of antiviral therapy in newborns is still under investigation. Early diagnosis and intervention are crucial to managing the disease and preventing long-term complications.
==Prevention==
==Prevention==
Preventive measures for HCMV include practicing good hygiene, such as handwashing, and avoiding contact with bodily fluids of infected individuals. In healthcare settings, standard precautions are essential to prevent nosocomial transmission.
Preventive measures for HCMV infection include practicing good hygiene, such as handwashing, and avoiding contact with bodily fluids from infected individuals. In healthcare settings, standard precautions should be followed to prevent nosocomial transmission.
 
Research is ongoing to develop a vaccine against HCMV, which could significantly reduce the incidence of congenital infections and disease in immunocompromised individuals.
==Related Pages==
==See also==
* [[Herpesviridae]]
* [[Herpesviridae]]
* [[Congenital infection]]
* [[Congenital infection]]
* [[Immunocompromised host]]
* [[Immunocompromised host]]
* [[Antiviral drug]]
[[Category:Herpesviridae]]
[[Category:Herpesviridae]]
[[Category:Viral diseases]]
[[Category:Viral diseases]]
[[Category:Congenital disorders]]
[[Category:Congenital disorders]]

Latest revision as of 03:57, 7 April 2025

Editor-In-Chief: Prab R Tumpati, MD
Obesity, Sleep & Internal medicine
Founder, WikiMD Wellnesspedia &
W8MD medical weight loss NYC and sleep center NYC

Human cytomegalovirus
Cytomegalovirus
Synonyms HCMV, Human herpesvirus 5 (HHV-5)
Pronounce N/A
Specialty N/A
Symptoms Fever, sore throat, fatigue, swollen glands
Complications Congenital cytomegalovirus infection, hearing loss, vision loss, neurological damage
Onset Varies; congenital or acquired
Duration Lifelong latent infection
Types N/A
Causes Cytomegalovirus infection
Risks Immunocompromised individuals, pregnancy
Diagnosis Serology, PCR, viral culture
Differential diagnosis Mononucleosis, toxoplasmosis, rubella
Prevention Good hygiene, safe sex, screening blood products
Treatment Antiviral drugs such as ganciclovir, valganciclovir, foscarnet, cidofovir
Medication Ganciclovir, valganciclovir
Prognosis N/A
Frequency Common; 50-80% of adults infected by age 40
Deaths Rare in healthy individuals; higher in immunocompromised


Virus of the family Herpesviridae


Human cytomegalovirus (HCMV), also known as human herpesvirus 5 (HHV-5), is a member of the Herpesviridae family of viruses. It is a common virus that infects people of all ages and is often asymptomatic in healthy individuals. However, it can cause significant disease in immunocompromised individuals and is a major cause of congenital infections.

Virology[edit]

HCMV is a large, enveloped virus with a double-stranded DNA genome. It is classified as a betaherpesvirus, which is characterized by a slow replication cycle and the ability to establish lifelong latency in the host. The virus can reactivate from latency, particularly in individuals with weakened immune systems. The HCMV genome is approximately 230 kilobase pairs in length and encodes for a variety of proteins that help the virus evade the host immune response and establish infection.

Pathogenesis[edit]

HCMV is transmitted through bodily fluids such as saliva, urine, blood, and breast milk. Once inside the host, the virus can infect a wide range of cell types, including epithelial cells, endothelial cells, fibroblasts, and leukocytes. In healthy individuals, HCMV infection is usually asymptomatic or may cause mild flu-like symptoms. However, in immunocompromised individuals, such as those with HIV/AIDS, organ transplant recipients, or patients undergoing chemotherapy, HCMV can cause severe disease, including pneumonia, retinitis, and gastrointestinal disease.

Congenital Infection[edit]

CMV placentitis

HCMV is the most common cause of congenital viral infection, affecting approximately 0.5% to 2% of all live births. Congenital HCMV infection can lead to a range of outcomes, from asymptomatic infection to severe disease with long-term sequelae such as hearing loss, developmental delay, and microcephaly. The risk of congenital infection is highest when a primary maternal infection occurs during pregnancy. The virus can cross the placenta and infect the fetus, leading to placental inflammation and fetal damage.

Diagnosis[edit]

Diagnosis of HCMV infection can be achieved through serological tests that detect antibodies against the virus, as well as molecular techniques such as PCR to detect viral DNA in blood or other body fluids. In congenital infections, diagnosis may involve testing the newborn's urine or saliva for the presence of the virus.

Treatment[edit]

CMV replication cycle

Antiviral drugs such as ganciclovir, valganciclovir, foscarnet, and cidofovir are used to treat HCMV infections, particularly in immunocompromised patients. These drugs inhibit viral DNA synthesis, thereby reducing viral replication. File:Hcmvdrugs.pdf Treatment of congenital HCMV infection is more challenging, and the use of antiviral therapy in newborns is still under investigation. Early diagnosis and intervention are crucial to managing the disease and preventing long-term complications.

Prevention[edit]

Preventive measures for HCMV infection include practicing good hygiene, such as handwashing, and avoiding contact with bodily fluids from infected individuals. In healthcare settings, standard precautions should be followed to prevent nosocomial transmission. Research is ongoing to develop a vaccine against HCMV, which could significantly reduce the incidence of congenital infections and disease in immunocompromised individuals.

See also[edit]