Preventable contagious diseases, such as measles and whooping cough can make a comeback primarily due to concerns over vaccine risks.
A new study, published in PLoS Computational Biology, shows how to predict ways in which population vaccinating behavior might unfold during a vaccine scare.
"These findings might help in evaluating and developing global immunization programs and public health policy", said Professor Chris Bauch of the University of Guelph's Department of Mathematics and Statistics.
The model captured the interplay between disease dynamics and vaccination behaviour during those episodes. One of the theoretical dynamics for the model was the phenomenon known as "herd immunity"; an entire population—including unvaccinated individuals—can be protected from infection by vaccinating only a certain percentage of the population. This suggests that immunization programs can be victims of their own success as past vaccinations drive disease incidence to such low levels that unvaccinated individuals feel no incentive to get vaccinated, creating ideal conditions for vaccine scares and thus future outbreaks.
Due to these conditions, as Prof. Bauch says, "Vaccine scares could become more common as eradication goals are approached for more vaccine-preventable diseases. Such models could help us predict how vaccine scares might unfold and assist in mitigation efforts."