by Dr. Michael Pfleiderer
Holiday season is over and seasons quickly turn from summertime to wintertime. Shorter days and colder temperatures are accompanied by the yearly official reminders released by vaccination advisory committees not to forget the annual shot of influenza vaccine in order to update immune protection against drifted influenza virus strains.
Meanwhile, numerous vaccines are available including tri- and tetravalent vaccines, inactivated and live attenuated vaccines, unadjuvanted and adjuvanted vaccines. Moreover, age indications are very heterogeneous ranging from 6 months of age upwards to over 65 years only.
This puzzling situation is further complicated by the fact that efficacy and effectiveness of various seasonal influenza vaccines is quite heterogeneous in different age and risk categories turning choice of the right vaccine into a difficult exercise for both, doctors and vaccines. Furthermore, the short shelf life naturally inherent to seasonal influenza vaccines is problematic for regions with untypical and repeated epidemiological patterns not matching with those of the Northern or Southern hemispheres for which most of the globally available influenza vaccines are tailor made for.
For those regions, suitable vaccines are either not available or shelf life of available vaccines may have already expired when these vaccines are needed. To simplify these rather complex scenarios scientists and regulators call since a long time for next generation influenza vaccines providing broader protectivity across strains and seasons, circumnavigating the need for seasonal revaccination and being freed from stringent production cycles. WHO is coordinating these initiatives and has recently launched a Preferred Product Characteristics (PPC) document summarizing the requirements for better or next generation influenza vaccines. We have been deeply involved in these activities by contributing to the drafting and finalization process of the PPC document. Read more about the WHO PPC concept.