text: Treatment and Prevention:\nThere is no specific treatment. Secondary bacterial infections may be treated with antibiotics. Live vaccines are available for vaccination of antibody-negative breeder flocks prior to the start of egg production. Administration is by injection or by addition to the drinking water depending on the type of vaccine available in individual countries. In some areas, transfer of litter to noncontaminated premises and the addition of crude homogenates of tissues from affected chickens to the drinking water have been used to ensure infection and seroconversion of parent flocks before they begin to lay, thereby diminishing the risk of egg transmission. However, these procedures are risky and not recommended. Because of the synergism between CAV and other immunosuppressive viruses, control of the latter is also important.\nAt present, there is no vaccine available to prevent subclinical losses in broilers.