Two new nasally administered vaccines for respiratory infections are being tested, and researchers now say that giving them together to young children appears feasible.

Respiratory syncytial virus (RSV) and parainfluenza virus 3 (PIV3) are important causes of serious respiratory tract diseases in infants and toddlers, according to a report in the Journal of Infectious Diseases.

Dr. Robert B. Belshe from Saint Louis University, Missouri, and colleagues evaluated intra-nasal RSV and PIV3 vaccines given either simultaneously or separately in an early-stage study involving 54 healthy children between 6 and 18 months old.

Both the RSV and the PIV3 vaccines induced immunity, the investigators report, and the frequency of protective antibody responses for RSV and PIV3 did not differ significantly between the separate and simultaneous vaccine groups.

None of the children developed a respiratory infection resulting from vaccination, the researchers note, and all vaccine recipients showed a similar pattern of illnesses to that seen in placebo recipients.

“The results of the present test-of-concept trial provide the framework for future development of bivalent RSV/PIV3 vaccine,” the team concludes.

SOURCE: Journal of Infectious Diseases, December 15, 2004.