An inactivated mycoplasma pneumoniae vaccine

An experimental vaccine was prepared withMycoplasma pneumonia, the agent of primary atypical pneumonia. Its injection elicited antibody in rabbits and monkeys and induced resistance to multiplication of myoplasma in lungs of vaccinated hamsters. The vaccine was well tolerated in preliminary studies with 36 human subjects, and encouraging evidence of antigenicity was obtained when 25 of 30 developed significant rises in mycoplasma growth-inhibiting antibody titers. The response was best (17 of 19) in men in whom prevaccination antibody was absent or low. The vaccine was prepared with a new culture medium in which chloroform extract of egg yolk and a chemically defined salt-amino acid-vitamin solution was substituted for the allergenic horse serum and beef infusion components of standard medium.