To the Editor.— We have recently observed a severe local and systemic reaction to pneumococcal vaccine. Report of a Case. — A 49-year-old woman was given 0.5 mL of pneumococcal vaccine intramuscularly in the left triceps. On the day after vaccination, the patient complained of severe frontal headache, nuchal pain, photophobia, nausea, and vomiting, as well as pain and swelling at the injection site. She was admitted to the hospital. Past medical history included pneumonia one year before admission (cause not determined, although no pneumococci were cultured) and recurrent sinusitis. She reported having a serum-sickness-like reaction to equine tetanus antisera in the remote past. Physical examination disclosed an acutely ill patient with a temperature of 39.8 °C. There was an area of induration and tenderness measuring 7 cm at the injection site. The left upper arm was erythematous, swollen, and painful on movement. The neck was supple. Findings from neurological