The Davison Group
Human cytomegalovirus (HCMV)
Human cytomegalovirus (HCMV) is one of nine herpesviruses that infect humans, and has the largest genome – at 236 kbp – of all known human viruses. Primary infection usually occurs at an early age via bodily fluids, and is followed by latency for life. Seroprevalence among older adults has been estimated at 60% or more in developed countries, and may be even higher elsewhere. Infection is often inapparent, but can be problematic in certain people, especially those who have immature or impaired immune systems.
Image: 'Genetic map of HCMV strain 'Merlin'. Characterisation of HCMV has helped pave the way to new HCMV'
There are two situations of particular clinical prominence. HCMV can cause serious disease in babies infected before birth and is a major cause worldwide of congenital infections, which can lead to permanent developmental or neurological impairments.
HCMV is also a leading cause of morbidity in solid organ and bone marrow transplant patients. This risk is exacerbated by the immunosuppressive therapies used to prevent rejection. Patients are treated pre-emptively or prophylactically with antiviral drugs. However, these treatments may lead to toxicity and to the selection of resistant mutants that are difficult to combat.