Vaccines for parenteral use
Modified live-virus (MLV) and inactivated vaccines can be produced in cell culture, using either primary cells or continous cell lines. The seed virus/cell systems vary considerably between different manufacturers. Increasing use of inactivated vaccines for animal immunization can be expected as a result of recent improvements in vaccine production techniques.
For mass canine vaccination campaigns, the use of inactivated rabies vaccine is recommended. The management of inactivated vaccine in the field is easier than that of live vaccine, since it is less sensitive to changes in temperature. Furthermore, accidents of self-inoculation do not represent any risk for the vaccinator.
At least 75% of the dog population in each community should be vaccinated within a month. In areas where the dog population turnover is rapid, it may be necessary to carry out a mass vaccination campaign each year. However, if the effective immune period of the vaccine is longer and the system for identifiying vaccinated dogs can be trusted to last more than one year, the advantage of vaccinating only the dogs entering the population after the last campaign should be considered, with revaccination of dogs vaccinated during the last campaign at intervals of about 2 years.
Combined vaccines are already used for the immunization of dogs and cats. Several different antigens are incorporated in canine rabies vaccine, such as canine distemper, canine hepatitis, leptospirosis and canine parvovirus. Combined rabies vaccines for cats may include various other antigens such as feline panleukopenia virus, feline calicivirus and feline parvoviruses. A combined rabies and foot-and-mouth disease vaccine is available for use in cattle, sheep and goats.