Cytomegalovirus infection is caused by human cytomegalovirus (HCMV), and China has a high prevalence of HCMV infection, most of which is acquired in childhood. Most infected individuals are asymptomatic, but congenital infection and immunosuppressed individuals can cause severe disease, and infection in infancy and early childhood often involves the liver. Susceptible pregnant women should avoid contact with the secretions of children known to have excreted the virus. The use of frozen deglycerinized blood products or washed cells may reduce post-transfusion infections. Prophylactic administration of acyclovir or ganciclovir before and after transplantation has been reported to reduce the incidence of HCMV disease in transplant recipients, but there are also reports that do not support this. The use of antiviral drugs plus intravenous immunoglobulin or highly potent HCMV immunoglobulin has been suggested to prevent HCMV disease in some high-risk transplant patients. The issues of vaccine virus latency and potential carcinogenicity of live attenuated vaccines have not been addressed, and their immunogenicity needs further study. Subunit vaccines such as the gB subunit vaccine are being studied, and the gH envelope glycoprotein and pp65 matrix protein are also being considered for the preparation of subunit vaccines. Treatment: 1. Antiviral therapy. There are two main drugs currently used in children: ① Ganciclovir (GCV): the first-line drug for severe HCMV infection in children, the treatment protocol refers to adults, induction therapy: 5mg/kg, q12h, intravenous drip, takes >1 hour, for 2-3 weeks; maintenance therapy: 5mg/kg, qd, for 5-7 days, if the maintenance phase of disease progression, can be considered again induction therapy If the disease progresses during the maintenance phase, re-induction therapy may be considered. The dosage should be reduced for those with renal impairment, and attention should be paid to adverse effects such as bone marrow suppression. ②Phosphonic acid (PFA), generally used as an alternative drug, can be used alone or in combination with GCV. PFA is nephrotoxic and is easily deposited in bone, teeth and cartilage. Dose reduction is required in patients with poor renal function. PFA is often not as well tolerated by patients as GCV, and HCMV strains resistant to PFA have been identified. 2. Symptomatic treatment. HCMV-related diseases should be treated accordingly, such as enzyme-lowering, anti-yellowness and hepatoprotective treatment in case of hepatitis; oxygen therapy in case of pneumonia with respiratory distress; pay attention to the prevention and control of secondary infection.