ABSTRACT
Booster doses of MMR vaccine equal in dosage to injected doses were aerosolized into a 3/4 l bag that inflated in 4s. The bag was then attached to valved masks, and its contents rapidly inhaled in one or two deep breaths by preschool Mexican children. Antibody responses in the children exposed to the aerosolized measles component were superior to those noted after injection, while responses to the mumps and rubella components were equivalent. The new method appears to be effective, safe, and has several advantages over previously used methods. Further explorations of the approach seem merited.
Subject(s)
Aerosols/administration & dosage , Equipment and Supplies , Immunization, Secondary/methods , Measles-Mumps-Rubella Vaccine/immunology , Administration, Inhalation , Antibodies, Viral/blood , Child , Child, Preschool , Female , Humans , Immunization, Secondary/adverse effects , Male , Masks , Measles-Mumps-Rubella Vaccine/administration & dosage , Measles-Mumps-Rubella Vaccine/adverse effects , MexicoABSTRACT
Measles vaccination via the aerosol route has proven effective under field conditions, using vaccine reconstituted prior to nebulization. Inhalation of a dry powder aerosol vaccine would have additional benefits, including easier logistics of administration, reduced cold chain dependence and the potential of single dose administration. We have evaluated two candidate dry powder measles vaccine formulations in macaques. Specific immune responses were demonstrated, but levels of immunity were lower than in animals vaccinated by injection or by nebulized aerosol. These studies provide proof of principle that dry powder inhalation is a possible route for measles vaccination, but suggest that either the vaccine formulation or the method of delivery need to be improved for a better immune response.
Subject(s)
Measles Vaccine/administration & dosage , Measles Vaccine/therapeutic use , Administration, Inhalation , Anesthesia, Endotracheal , Animals , Antibodies, Viral/analysis , Antibodies, Viral/biosynthesis , Injections , Lung/metabolism , Macaca fascicularis , Measles/immunology , Measles/prevention & control , Measles virus/chemistry , Neutralization Tests , Particle Size , Powders , RNA, Viral/analysis , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , Vaccination/methods , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/therapeutic useABSTRACT
The comparative efficacy and safety of measles vaccination via the aerosol route versus subcutaneous injection has not been fully resolved. We vaccinated cynomolgus monkeys (Macaca fascicularis) with the live-attenuated Edmonston-Zagreb measles virus (MV) vaccine and compared different routes of administration in the immunocompetent and the immunocompromised host. Immunogenicity and protective efficacy of aerosol vaccination using devices similar to those previously used in humans were comparable to those in animals vaccinated by injection. No evidence for a safety hazard associated with the route of vaccination was detected. The results of this study support further clinical evaluation of aerosol vaccination for measles.