Vaccines and Vaccination PDF

PID: Vaccines and Vaccination George Nadăș ,Professor of Immunology, [email protected] LEARNING OBJECTIVES Define passive and active immunization Recognize the different types of vaccines and understand their advantages and disadvantages Understand the concept of vaccine efficacy Understand the ro...

PID: Vaccines and Vaccination George Nadăș ,Professor of Immunology, [email protected] LEARNING OBJECTIVES Define passive and active immunization Recognize the different types of vaccines and understand their advantages and disadvantages Understand the concept of vaccine efficacy Understand the role of adjuvants Understand vaccine adverse events 2 HISTORY OF IMMUNIZATION ancient vaccines been since have used times previously variolation caned but 15th century China - Variolation InisIiras iI.YmYrraintisin'In rea It siii wn resistance Observed that individuals who recovered from smallpox never suffered from it a second time Deliberately infecting children by placing the dried scabs in a small incision in the arm, resulting in local disease (less severe and lower mortality) The technique spread westward along the Silk Road until it eventually reached the Ottoman Empire—modern Turkey It was widely employed across the Middle East Reached England in the 1700’s 3 HISTORY OF IMMUNIZATION p rotection cross fromacowpox virus able s mallpox from is toprotectindividual 1796 - Edward Jenner Milkmaids seemed to not fall ill from smallpox Infection with cowpox protected then against smallpox Pus from a lesion of cowpox injected into a boy named James Phipps Later, he infected James Phipps with smallpox The boy survived Vaccination ➡Vacca means cow in Latin 0 0 4 HISTORY OF IMMUNIZATION to discoveries relatedaccidents most major are iiiaiiiii.in in iiiiiimuitociaainsnn Louis Pasteur firstintheinvaccine 1879 - Pasteurella multocida vaccine in chickens (attenuated bacteria) For many, the birth of Immunology 1881 - Anthrax vaccine in ruminants removing c apsuleinanthrax madeit to 1885 - Rabies vaccine ofimmune 9y boy bitten by a rabid dog 12 consecutive injections The boy survived 1886 - Mortality dropped to 0.5% after vaccination p roduced phagocytosis response nonresistant exposure from post unlessvaccinatedorbenefit to rabies infection prophylaxisunlikely s urvive 5 TYPES OF IMMUNIZATION Passive vs Active PASSIVE IMMUNIZATION requires effort no ACTIVE IMMUNIZATION resistant becoming ADMINISTRATION OF ANTIBODIES Natural: e.g., Colostrum Artificial: e.g., Antivenom ADMINISTRATION OF ANTIGENS Natural: Infection Artificial: Vaccination soonafterbirth24 ashrs 6 TYPES OF IMMUNIZATION Passive Immunization passivelytransferantibodies iiiiiimain passive used Preformed antibodies specific to a particular antigen antibodiescoatantigen Immediate/short-lived protection No immunological memory immunization especially innorses preventative and swine for measures 1 If in mon Less used in veterinary medicine 7 in TYPES OF IMMUNIZATION t.hn Active Immunization 1min18sMou's a cHimI m before developor clinical antigen the signs gridlydestroy p shed Antigen is administered Induces an immune response and immunological memory memoryB cells memorycells Most common form of immunization Vaccines 8 TYPES OF IMMUNIZATION Passive vs Active iiiiiiiiiiii.in innnania buttnentneimmunesustemwinconsidertn.se antibodies asnonseitanatriggerimmuneresponse.gr uweers titeror concentration antibodies of win vaccines some m onovalent are single exampledistemper turefor inaogs.someotnersareaeveiope anaromvaient.incinaingsormoreaitte.int products antigen i fiiiiiiiiii in i n in 9 DO VACCINES REALLY WORK? Vaccination is the most efficient and effective method of controlling infectious diseases ever developed. Eradication of infectious diseases are great examples: worldwide eradication Smallpox ago Rinderpest - “Cattle plague” zooa.z.ro 10 SMALLPOX VACCINE IMPACT SMALLPOX ERADICATION comparativesituationoncontinents 1 2 3 1.1959: WHO resolution on smallpox eradication 2.1967: start of intensified eradication program 3.1977: Last case of smallpox iiiiii9m intensifiedvaccination program 1980: WHO officially declares smallpox eradicated need c ases atleastyearsof to no declareeradication 12 RINDERPEST ERADICATION important point ★Middle East ★Africa ★Asia ★Europe easieraccomplish eradication global aaneasetnat.nu asingie.pe targets example unlike for rabies union ismor iteicaitanetow.la a reservoirsoats s raccoons etc 13 VACCINE EFFICACY Vaccine Efficacy is generally expressed as a reduction in disease attack rate (AR) between the unvaccinated (ARU) and vaccinated (ARV) individuals: VE = ARU − ARV × 100 ARU Attack rate in this case may refer to different outcomes: Death; Severe Disease; Clinical Disease; Infection, and etc… The same vaccine may have different efficacies for each outcome 14 TYPES OF VACCINES HOW IT STARTED: HOW IT’S GOING: msn.i.wn.am iiiiii iii iii i Live-attenuated thinkinthe need rarely angie Killed/inactivated vaccines antennamenamnet.in Component vaccines Toxoid vaccines advantage boosters rosters man.es immunity snort Ii ititI a immunity's snort months iiiiii pathogenicity reduce only theessentialelements inject for to naviggygyne Molecular based technologies Chimeric organisms Recombinant subunit Recombinant-vector vaccines Nucleic acid vaccines Virus-like particles gene that's Reverse vaccinology injectonly for invitro inlab s equence essential pathogenicity infections entire agent pathogen the not of an invivo inexperimentalanimals insilicoinianusingcomputerstimulation 15 TYPES OF VACCINES O O O EYE vaccine booster annual required usually disadvantages P tiersstimulation 99.11.5 Ethmunity 16 Live attenuated vaccine Att. Pathogen I Dead Pathogen Attenuation Inactivation Pathogen Subunit protein gene Subcloning e.me Live vector vaccine yan.ge Cloning inants Fractioning ieiiiiiiiiiiii iii Nucleic acid vaccine Expression Non pathogenic MO Killed/Inactivated vaccine iiii.it i iiiii iiiiiiiii.li Recombinant subunit vaccine i iii Subunit vaccine 17 TYPES OF VACCINES DIVA vaccines Differentiate Infected from Vaccinated Animals animals a'initiated fit th iiiiiYou aSan man removal f surface ofoneothe proteins that orepitopes in are important pathogenicity L 18 NUCLEIC ACID VACCINES DNA vaccines bacterial diseases differentiated a gainst imrnaaitterentiateaagainstviraiaisea.es iti iii i i i iiiiii in Plasmid containing gene for the target antigen DNA in the cell generates mRNA from which the antigenic protein can be expressed Antigen presented by dendritic cells to lymphocytes 19 NUCLEIC ACID VACCINES DNA vaccines itiiiiiiiii i iii iiiiiiiii 20 NUCLEIC ACID VACCINES mRNA vaccines ainitial diseases oflipidnanoparticle injection 11 inam isproteinspikeprotein min protein RECOMBINANT ORGANISM VACCINES Clone the gene that codes the immunogenic protein signorina Insert it into a vector A virus incapable of causing disease in the host RECOMBINATION A vaccinated host will be infected with the vector Induces an immune response 22 RECOMBINANT ORGANISM VACCINES Clone the gene that codes the immunogenic protein Insert it into a vector (virus incapable of causing disease in the host) A vaccinated host will be infected with the vector Induces an immune response 23 ADJUVANTS Substances that facilitates or enhances immune response to an antigen with which it is combined immune stirrup 24 ADJUVANTS important in stowremovalot ftp.tfgfffatio antigenanaproionged response immune tableisjustr.ua qq.ttIr ARE VACCINES DANGEROUS? 26 VACCINES & AUTISM Andrew Wakefield - Lancet, 1998 “Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children” Relation between the MMR (Measles, Mumps, Rubella) vaccine with autism and IBD Issues: No control group No statistical analysis Vague conclusions Misrepresentation of study subjects medical records VACCINES & AUTISM Failed to disclose financial interests Funded by lawyers who had been engaged by parents in lawsuits against vaccine manufacturers Had applied for a patent on a new vaccine against measles VACCINE ADVERSE EVENTS As with any medication, the use of vaccines is not free of risks Adverse events should be recorded and reported Basic principles to identify a VAE 1. Consistency: repeatable in different groups receiving the vaccine 2. Specific: linked specifically to the vaccine concerned 3. Temporal relationship: vaccination should precede the event 29 Results: 1,258,712 vaccine doses 496,189 cats 2,560 VAAEs 92% in 0-3 days 51.6 VAAEs/10,000 cats 4 cats died within 48h 0.081 deaths/10,000 cats 30 Results: 1,226,159 dogs 496,189 cats 4,678 VAAEs 38.2 VAAEs/10,000 dogs 3 dogs died 0.024 deaths/10,000 dogs 31 PID: Vaccines and Vaccination ©2024 Ross University School of Veterinary Medicine. All rights reserved.