The greatest care is taken during the preparation of vaccines and each batch is subjected to numerous quality tests according to strict national and international prescribed quality assurance protocols. These tests are necessary to ensure that all vaccines issued are pure, safe and effective. Some tests are even included to ensure that vaccines will retain their efficacy during transportation when they are exposed to environmental temperatures.

Despite all care taken during the production of vaccines, OBP periodically receives complaints concerning supposedly ineffective vaccines. Indeed, no vaccine is 100% effective in all animals and this fact is indicated in the pamphlets accompanying all vaccines. There are various factors which may influence the efficacy of vaccines. It is therefore important to follow careful instructions on handling and administering vaccines in order for the immunization to be effective.