Human Cytomegalovirus (CMV) is a member of the family Herpesviridae, also known as Human Herpesvirus 5 (HHV-5). It is the largest (220 nm in diameter) and most complex herpesvirus.

Many people will get infected in their lifetime, but most will have mild or no symptoms. Pregnant females infected with CMV can give birth to a baby with congenital CMV. Congenital CMV can cause hearing loss and developmental issues. CMV can cause serious complications in people who have a compromised immune system, such as transplant recipients.

CMV detection is particularly important in certain populations, such as pregnant women (to assess the risk of congenital CMV in newborns), individuals with weakened immune systems (to prevent CMV-related complications), and newborns showing symptoms suggestive of congenital CMV infection. PCR tests detect CMV DNA in blood, urine, saliva, or other bodily fluids. PCR is highly sensitive and can detect the presence of CMV even in asymptomatic individuals.