Viral studies in benign acute childhood myositis.

Thirty-five cases of benign acute childhood myositis followed infections with influenza A or B. Two children had recurrent myositis associated with infections of different influenza types. None of the children had acute-phase antibody titers to the infecting type of influenza. These results are consistent with the proposal that benign acute childhood myositis can occur only with the initial infection of a viral type.