How often does chicken pox lead to respiratory failure?

Rarely: Very rarely, but I have seen this happen. Thus the importance of immunization with the safe vaccine.

Around 40%: Varicella (chicken pox) pneumonia is rare, but has been cited to occur in about 1 in 400 adults with varicella infection. Of those patients that develop varicella pneumonia, approximately 40% may develop respiratory failure. Although respiratory failure is a significant cause of mortality in varicella infection, the majority of patients do recover.

Two groups: Infants that develop varicella during delivery or their first week will have no protection from major complications.By definition they had it at the same time as their mother and have no protective antibody.Death with varicella pneumonia can be avoided if the kid receives Immune Globulin immediately after birth and oral antivirals.Adults with primary varicella are also at risk.