Presentation of the directive 81/852/EEC (92/18) safety testing.

The aim of the directive is to define tests to be done by a manufacturer which are capable of providing as precise information as possible about the properties of the biological products concerning safety. These tests have to be done in the target species and the dose used should be that quantity of the product recommended for use and containing the maximum titre of potency. The samples for safety testing should be taken from a batch produced according to the manufacturing process. The vaccine is tested in normal conditions at the recommended dose and by each recommended route of administration to animals of each species and category it is intended to vaccinate. Objective criteria have to be recorded to measure possible adverse general and local effects. But tests in abnormal conditions of use may be necessary, such as administration of an overdose or repeated administration of one dose. Effects on reproductive function and progeny have to be studied as well as investigations which may be required in some cases to evaluate a possible adverse effect on the immunological function of the vaccinated animal. Special requirements seem to be appropriate for live vaccines: to evaluate the spread of the vaccinal strain from vaccinated to unvaccinated animals including, if necessary, wild species; to determine whether the vaccinal strain can disseminate in the vaccinated organism; to check for the absence of reversion to virulence of live stains especially for conventional vaccines. Field studies can therefore provide complementary information about safety.