The National Network for Immunization Information (NNii) provides up-to-date, science-based information to healthcare professionals, the media, and the public: everyone who needs to know the facts about vaccines and immunization.

Vaccine Safety

Asthma and Vaccines

The prevalence of childhood asthma has been increasing in the past two decades in the United States.  Some have suggested that this increase may be due to vaccinations, although recent studies do not support that hypothesis.


For Professionals

This section includes links to general immunization recommendations in the United States and other valuable information for health professionals.