Virus Isolations from Common Colds Occurring in a Residential School

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 (Andrewes et al., 1961).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).We were anxious to make a longitudinal study to determine if viruses could be found consistently in young persons with common-cold symptoms, and, if so, to obtain a full record of illness.We also hoped to obtain some data of epidemiological importance.Such a pilot study is described in this paper.It was made as part of a general surveillance of respiratory illnesses which significantly affect school attendance. Materials and MethodsThe common colds studied occurred among boarders at a boys' school which was under the medical care of one of us (E.J. C. K.).The age constitution of this group is given in Table I.The boys were observed TABLE I.-Age Constitution of Group, Incidence of Colds, and Nunmbers of Illnesses Investigated 1960-1 Year of Birth: 1947-8 1946 1945 1944 1942-3 No. of boys in group on 1 1 61 84 68 60 79 77 common colds ascertained 67 48 34 46 30 Incidence of common colds .. 80% 70% 57% 58% 39'% No. of virus-positive illnesses/No. of illnesses investigated 9.'23 2 14 2 '9