ABSTRACT Vaccination is one of the most cost-effective interventions for control of communicable diseases. This health achievement could founder if measures are not taken by health systems to prioritize immunization, increase vaccination rates and educate health professionals to address public concerns about vaccine safety and efficacy. Parents’ refusal to vaccinate their children directly affects public health, because it puts both individual and group immunity in danger; immunization coverage is effective only when high population coverage is attained. The growing number of antivaccination (antivaxxer) groups around the world is alarming, contributing to falling vaccination rates. Troubling consequences include disease outbreaks in several countries globally and in our hemisphere. This article looks at the history and features of antivaxxer movements around the world and proposes ways the Cuban health system, through its National Immunization Program, can address dangers for the population associated with potentially negative influences of social-network antivaxxer campaigns. The paper underscores the role of mass and social media, health professional training and sustained competence, and the importance of a vaccine-related adverse events surveillance system.