Dr van Wessum is a veterinarian with years of experience as FEI competition vet at several FEI CDI CSI shows in the Netherlands.

He is certified by the Dutch Royal Equestrian Federation to prepare and validate FEI passports. Getting these FEI passports acceptable for official FEI competitions requires distinct and adequate up-to-date knowledge of the FEI regulations about vaccination, medication and the guidelines how to fill in the diagram and written outline of the horse.

He can assist competitors about interpretation of the FEI regulations and rules, especially when focused on medication and doping.