The occurrence of sepsis due to Streptococcus pneumoniae and Hemophilus influenza and of herpes zoster (HZ) was reviewed in a series of 72 consecutive, previously untreated children and adolescents with Hodgkin disease. There was not a statistically significant difference in the risk of developing sepsis within five years of diagnosis between patients who had (16.6%) or had not (6.2%) undergone splenectomy. Sepsis occurred most frequently among patients treated initially with total nodal irradiation and combination chemotherapy. The estimated risk of HZ during the first five years after diagnosis was 34%. Patients treated initially with irradiation and combination chemotherapy had a significantly greater risk of developing HZ than patients treated initially with only irradiation (P less than 0.05). Although trends were present which suggested that splenectomy and the extent of disease at diagnosis may influence the occurrence of HZ, these did not achieve statistical significance. Survival was not influenced by the occurrence of HZ.