What is the risk of CMV transmission?
CMV transmission is associated with the transfusion of cellular components. This means that fresh frozen plasma (FFP), cryoprecipitate and other plasma-derived components do not require CMV screening.
All cellular products in Australia are leucodepleted. Neither leucodepletion nor CMV seronegativity completely eliminates the risk of CMV transmission. Some data suggests CMV seronegative components and leucodepleted components have the same risk of CMV transmission. Whether using a combination of leucocyte depletion and CMV-seronegative components provides any additional safety benefits is unknown. For at-risk patients, early detection of CMV infection by polymerase chain reaction (PCR) monitoring should be considered.
When should I use this modification?
CMV seronegative products should be used for the following clinical indications:
- pregnant women regardless of CMV status who require regular elective transfusions during pregnancy (but not during delivery)
- recipients of intrauterine transfusions IUT
- neonates (up to 28 days post expected date of delivery), and
- granulocyte transfusions for CMV negative patients.
For other groups, the use of CMV seronegative or leucodepleted blood products (i.e. CMV safe), will be dictated by local clinical policies:
- solid organ transplants
- haemopoietic stem cell transplants (HSCT)
- haematology and oncology patients, and
- immunodeficient patients, including those with HIV.
For further details, consult the ANZSBT Guidelines for Transfusion and Immunohaematology and Laboratory Practice.
Guidance on the use of CMV seronegative platelets during supply shortages can be found in the platelets response plan (annex C) of the National Blood Supply Contingency Plan.