INTRODUCTION TO CYTOMEGALOVIRUSES
Cytomegalovirus (CMV) is formerly known as salivary gland virus, are a group of Herpes viruses, characterized by enlargement of infected cells and prominent Intranuclear inclusions.
INFECTIONS CAUSED BY CYTOMEGALOVIRUS
⇒ The source of the infection is usually by direct contact with body fluids, such s Saliva, Blood, Urine, Semen, Vaginal fluids, and Breastmilk.
⇒ Most healthy people do not experience any symptoms when infected with CMV, and it doesn’t pose a serious health concern.
⇒ In those children and adults who do have symptoms will recover from CMV infection without complications and do not require antiviral treatment.
⇒ In those with weakened immune system, CMV can cause serious disease (Retinitis Hepatitis, Colitis, Pneumonia, or Encephalitis).
CLINICAL FEATURES OF CMV INFECTION
⇒ The symptoms of Acute CMV infection include:-
- Enlarged lymph nodes
- Sore throat
- Muscle aches
⇒ Hepatitis like signs includes – Appetite loss, Yellow eyes, Nausea & Diarrhea.
⇒ In Immuno-compromised individuals, CMV infection can attack different organs of the body & may cause blurred vision and blindness, Lung infection, Diarrhea, Hepatitis or Encephalitis.
⇒ Congenital CMV shows the symptoms of Deafness, Jaundice, Skin rash, Pneumonia, Spleenomegaly, Hepatomegaly, Microcephaly or Seizures.
PATHOGENICITY OF CYTOMEGALOVIRUS
⇒ The virus may be transmitted from person to person in several ways – close contact with virus bearing material, blood transfusion, sexual contact etc.
⇒ The incubation period of CMV is 4-8 weeks.
LABORATORY DIAGNOSIS OF CYTOMEGALOVIRUS
⇒ Specimen: The virus can be isolated from Urine, Saliva, Breast Milk, Semen, Cervical secretions, Blood Leucocytes.
⇒ Isolation of Virus: Virus can be grown in Human amnion, Human Fibroblast, HeLa or Vero cell cultures.
⇒ Antigen detection: CMV antigen can be detected by blood leucocytes using monoclonal antibodies.
⇒ Polymerase Chain Reaction: PCR is the most widely used molecular method for detection of CMV DNA.
TREATMENT OF CMV INFECTION
⇒ Ganciclovir & Foscarnet have been found to be effective and are used for the treatment of CMV disease in patients with AIDS.
PROPHYLAXIS OF CYTOMEGALOVIRUS INFECTION
⇒ Screening of blood and organ donors and administration of CMV immunoglobulin have been employed in prevention.
⇒ Acyclovir is useful in prophylaxis but not in treatment.
⇒ No vaccine is available.