Vaccines and evolution: Why is it important to understand the genetic diversity of pathogens?

Abstract

From the perspective of public health intervention, there is no better weapon than one which can prevent disease transmission or onset. Within the field of infectious diseases, vaccines have become the weapon that can control many of them. Today, however, there are a large number of emerging infectious diseases for which no vaccines exist, or long forgotten diseases that are re-emerging. New vaccines are being developed to attack the pathogens associated with them. However, despite the importance of good vaccine design, the genetic diversity of pathogens is not always taken into account. Studying their diversity helps identify how pathogens adapt to pressure from the immune system and to what extent the immune response benefits the host or, conversely, benefits the pathogen. Understanding these relationships will help us predict how effective and universal a vaccine can be, and thus aid in their design.