SPECIFIC ANTIINFECTIOUS IMMUNITY. colostral immunity. administration of antibodies VIRULENT VACCINE INACTIVATED VACCINE

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1 INDUCTION OF IMMUNITY AGAINST INFECTION SPECIFIC ANTIINFECTIOUS IMMUNITY active passive S AND VACCINATION infection vaccination colostral immunity administration of antibodies VIRULENT MODIFIED LIVE INACTIVATED RECONVALESCENT, HYPERIMMUNE SERUM PASSIVE IMUNISATION hyperimmune sera used for treatment (or prevention) of infection less profitable than vaccines, useful specially in the incubation period or prodromal stage of infection rapid effect but the levels of antibodies rapidly decrease (no immunology memory) intramuscular or subcutaneus application examples: sera against parvovirosis or distemper SIGNIFICANCE OF VACCINATION - IMMUNISATION Vaccination is one of the basic tools of prophylaxis of infectious diseases Vaccination may result in inhibition of the development of infection and its clinical manifestations (the agent survives in the host organism) elimination of the agent from and inhibition of its penetration into the host complete eradication of the infection from the population

2 PRIMARY AND SECONDARY IMMUNE RESPONSE Log titre first dose primary response second dose secondary response lgm lgg weeks PREREQUISITES OF EFFECTIVE VACCINATION Good quality vaccine appropriate antigen and suitable antigenic spectrum correct formula (carrier, adjuvant) free of side effects good manufacture practice Correct immunisation scheme time of immunisation and revaccination and booster intervals suitable way of administration suitable combination with additional vaccinations Immunocompetent vaccinate with genetic predisposition free of immunosuppression or immunodeficiency without interference of passively acquired antibodies PROPERTIES OF GOOD POPULATION RESPONSE TO VACCINATION efficacy production of antibodies and/or cell-mediated immunity prevention against infection and illness safety non-pathogenic without adverse reaction These properties and other qualities must ensure the manufacturer in the registration process and during the good manufacture practice NUMBER OF ANIMALS PROTECTIVITY IMMUNITY

3 TYPES Generation I - conventional vaccines live attenuated, heterologous inactivated whole-cell (bacterin) toxoids subunit (purified or synthetic antigen) Generation II - recombinant vaccines subunit (inactivated) gene deleted (live) vector (live) Generation III - DNA vaccines LIVE contain live atenuated agent (virus) with possibility of limited replication in the host advantages does not cause disease but strongly stimulate cell-mediated and antibody immune response the duration of immunity is long disadvantage relative danger of reversion of virulence cant be used in immunosuppressed animals the agent can be spread among animals examples distemper, parvovirosis, other viral diseases oral vaccine against rabies used in wild animals INACTIVE contain dead (inactivated) agent (bacteria) or its part (one or more antigens) or toxin advantages relativelly harmless with possibility to stimulate antibody production can be used in immunocompromised animals disadvantage sometimes weekly immunogenic, it needs adjuvant does not stimulate cell-mediated immunity adjuvant can cause adverse reaction examples leptospirosis, bordetella vaccine, lyme disease rabies, coronavirosis, (parvovirosis) ADJUVANTS Adjuvant (and carrier) - binds antigen and enhances immune response - can induce local or general reactions aluminium hydroxide and other aluminium compounds better antigen binding - step-by-step release water-in-oil emulsion (oil-in-water) FIA, FCA good stimulation of immune reponse side effects are possible novel carrier types liposomes ISCOMs microspheric particles immunostimulants microbial products, saponin, vitamin E, cytokines

4 CONSTRUCTION OF SUBUNIT VIRAL MICELLE CONSTRUCTION OF NOVEL TYPES complete virion VIRION ISCOM gene introduced into plasmid of productive cell removed gene gene introduced into vector genome E. coli vaccinia virus VIRAL SUBUNIT LIPOSOME MICROSPHERE original virus proteins SUBUNIT virion with incomplete protein set GEN DELETED viral vector producing also proteins of the original virus VECTOR GENERAL PRINCIPLES OF ADMINISTRATION At least two aplication are desirable in basic (primary) vaccination schema The interval between first and second dose should not be shorter than 14 days, at best 3 to 4 weeks The basic immunisation should be done by the vaccine of the same company The booster dose is usually aplicated in 1 year interval but in some cases it should be done earlier or can be aplicated in longer interval MONOVALENT OR POLYVALENT S? ANIMALS CAN RESPONSE SIMULTANEOUSLY TO SEVERAL ANTIGENIC STIMULI Combinations offered by manufactuters should be considered Activity of each antigenic component of a polyvalent vaccine should be equal that of a monovalent vaccine Combination of vaccines intended for separate administration should be avoided

5 ANIMALS THAT MUST NOT BE VACCINATED sick animals animals treated with antibiotics or corticosteroids animals stressed by adverse hygienic conditions transport change of environment or regrouping pregnant animals shortly before parturition