Virus Isolations from Common Colds Occurring in a Residential School

Abstract

In recent years viruses of a hitherto uncultivable type have been isolated from nasal washings collected from adults suffering from the common cold (Tyrrell and Parsons, 1960; Hobson and Schild, 1960; Tyrrell and Bynoe, 1961 ; Hamre and Procknow, 1961). The viruses can be cultivated in rolled tissue cultures of human- embryo-kidney cells maintained at 330 C. They produce a focal cytopathic effect. It has been suggested that they be called rhinoviruses There is evidence that all the strains adequately studied produce colds when administered to volunteers as nasal drops and that the type of illness produced may vary a little, depending on the strain used. The viruses belong to two main biological types-namely, those which grow in human embryo-kidney and in monkey-kidney cells (M) and those which grow only in human-embryokidney cells (H); it has been shown also that some washings contain agents which have not yet been shown to grow in either of these cell types (Tyrrell and Bynoe, 1961).