Inactivated Parainfluenza Type 1, Type 2, and Type 3 Vaccines in Infants: Antigenicity, Safety

摘要

Inactivated viral vaccines for parainfluenza virus types 1, 2 and 3 were prepared in embryonated chicken eggs; type 1 in the allantoic cavity, types 2 and 3 in the amniotic sac. Ten infants received parainfluenza 1; ten received parainfluenza 2; and 16 received parainfluenza 3 vaccine. All infants received two injections at an interval of one month and each infant receiving the parainfluenza 1 and 3 vaccines received an additional injection 41 to 163 days after the second injection. These vaccines were 90% to 100% effective in inducing antibody response. The infants receiving parainfluenza 2 vaccine responded following two injections whereas a majority of those receiving parainfluenza 1 and 3 required the additional injection at a later interval. Infants receiving the parainfluenza 1 virus vaccine developed a complement fixing antibody response to material other than viral protein. There is evidence that this is some component of chicken embryo host which is included in the vaccine when vaccine is prepared in the allantoic cavity. During these studies a micro method for detection of neutralizing antibody seemed to correspond remarkably with the conventional method and was a much simpler and economical method to utilize. During these studies evidence was also obtained to suggest that repeated freezing and thawing caused a detruction of parainfluenza 2 virus neutralizing activity in infant serums. (Author)