We report seven cases of seven pulmonary varicella occurring in seven adults without any previous history of known immunological deficit. In all the cases the vesicular eruption was diffuse, occurring after contact with a child presenting with benign varicella. The respiratory signs appeared five to seven days after the cutaneous signs. On admission there was significant hypoxaemia (PaO2 = 35 to 47 mmHg on air), requiring positive pressure expiration (10 to 18 cmH2O) on mechanical ventilation (4 times) or spontaneous ventilation (3 times). The pulmonary radiographs showed diffuse nodular interstitial shadowing. Treatment consisted of Acyclovir (10 mg/kg/8 h). Five patients were cured without any sequellae five to six days after ventilation. One patient died (3 months pregnant), 1 patient presented with a superinfection with staphylococcus aureus. The occurrence of respiratory signs in an adult presenting with varicella requires hospitalisation for treatment with Acyclovir and also the prevention of superinfections.