Monitoring and analysis of vaccine concerns could help immunization programs adapt more effective and timely strategies to address public concerns, according to study results published in The Lancet Infectious Diseases.
“Although immunization has successfully reduced the global burden of illness and death, a range of concerns have converged to affect public confidence in vaccines,” researchers wrote. “When confidence in vaccination breaks down, hesitancy can lead to delays and refusal, disrupting research and delivery programs, and sometimes leading to disease outbreaks.”
The study included 10,380 reports from 144 countries regarding vaccines, vaccination programs and vaccine-preventable diseases collected between May 1, 2011, and April 30, 2012.
Researchers found that 60% of the reports contained positive or neutral content and 31% contained negative content.
Of the negative reports, 24% were related to vaccine programs and disease outbreaks; 21% to beliefs, awareness and perception; 16% to vaccine safety and 16% to vaccine delivery programs.
“We now have a growing body of evidence of the potential risks of the spread of unchecked rumors, and of failing to address legitimate questions and concerns,” researchers wrote. “Even if concerns driven by misinformation or reported adverse events are investigated and confirmed as not being caused by vaccines, concerns and reputations in the public mind need to be addressed.”
In an editorial accompanying the study, Natasha Sarah Crowcroft, MD, of Public Health Ontario and Dalla Lana School of Public Health, and Kwame Julius McKenzie, MD, of the department of psychiatry at the University of Toronto and Centre for Addictions and Mental Health, said surveillance of different safety concerns will help serve as a platform for research.
“Such surveillance gives concerns a greater profile, and emphasizes gaps in the public health system’s responses to and preparedness for vaccine safety events,” they wrote. “Bad news stories damage vaccination programs as much as biological hazards, and these stories evolve over minutes or hours, needing immediate action.”