WHAT DO YOU KNOW ABOUT VACCINES? Process in the body? Examples Invented by? Any worries? Interesting facts
Non specific immunity Inflammatory Non-specific Cellular response Physical & chemical barriers Specific immunity Immunological surveillance Clonal Selection theory T cells B cells Infectious Disease Transmission Epidemiology Vaccination Public Health Immune system diseases Disease survival mechanisms BIG PICTURE We are here
LEARNING OUTCOMES IDENTIFY THE 4 TYPES OF IMMUNITY AND WHICH ONE VACCINATION / IMMUNISATION / INOCULATIONS COMES UNDER CONSTRUCT THE ROUTE TO MARKET FOR A VACCINE THROUGH CLINICAL TRIALS START EXAMINING THE IMPORTANCE OF VACCINE UPTAKE
THIS IS HOW VACCINES PROTECTS YOU Glossary Keywords Pathogen – An agent that causes disease or illness. Antigen – A substance on the surface which will be recognised as non-self White blood cell – A blood cell that protects the body from invading microbes Antibody – A protein made by white blood cells to protect it from harm Immune – protected against a disease Memory cell – long term cells which allow a faster response if re-infected
IMMUNITY “THE ABILITY OF AN ORGANISM TO RESIST A PARTICULAR INFECTION OR TOXIN BY THE ACTION OF SPECIFIC ANTIBODIES OR SENSITIZED WHITE BLOOD CELLS”. CAN BE EITHER NATURALLY ACQUIRED (HAD THE INFECTION PREVIOUSLY) OR ARTIFICIALLY INDUCED (GIVEN THE PATHOGEN IN SOME FORM) CAN BE EITHER ACTIVE (PERSON’S OWN BODY PRODUCES ANTIBODIES) OR PASSIVE IMMUNITY (PASSED ANTIBODIES FROM SOMEONE/THING ELSE)
Four types of Immunity Passive Natural (another source of antibodies / white blood cells) Active Natural (body makes antibodies after exposure) Passive Artificial (another source of antibodies given) Active Artificial (body makes antibodies after pathogen given In some form) Immediate protection. Short term. Eg. Antibodies across placenta from mother to baby Eg. Ab’s from mother’s milk to baby Develop after lag time. Long lasting Involve memory cells. Eg. Natural exposure to chicken pox (foreign Ag’s stimulate Ab’s & memory B and T- cells) Immediate protection. Short term. Require medical treatment. Develop after lag time. Long lasting involve memory cells. Require medical treatment. Eg. direct injection of tetanus antibodies / snake bite Eg. Vaccination of MMR, whooping cough to stimulate specific immune response.
SOMETHING THAT INDUCES A PRIMARY IMMUNE RESPONSE AND IMMUNOLOGICAL MEMORY IN THE INDIVIDUAL BUT NOT DISEASE SYMPTOMS WHAT THINGS CAN ARTIFICIALLY STIMULATE AN IMMUNE RESPONSE?
Inactivated Toxin so harmless form Eg. diptheria vaccine (upper respiratory disease) and tetanus Weakened Pathogen Attenuated (weakened) form of the pathogen so easily overcome/ harmless Eg. measles vaccine/ mumps and rubella Dead pathogens Eg. Poliomyelitis and hepatitis A and whooping cough (pertusis) Parts of pathogen / Antigen from infectious pathogen Eg. HPV (human papilloma virus – cervical cancer, hepatitis B and meningitis C Boosters Ensure long-lasting immunity, but eg. Childhood boosters of tetanus. These agents induce a primary immune response and immunological memory in the individual but not disease symptoms.
SOMETIMES YOU NEED A LITTLE HELP FROM YOUR FRIENDS ADJUTANTS – A CHEMICAL SUBSTANCE THAT IS MIXED WITH THE ANTIGEN WHICH PROMOTES AN IMMUNE RESPONSE / PRODUCTION OF B AND T CELLS BY THE ANTIGEN
Vaccine controversy – how do we ensure safety?
VACCINE CLINICAL TRIALS... AS WITH ALL PHARMACEUTICAL MEDICINES VACCINES ARE SUBJECTED TO CLINICAL TRIALS BEFORE LICENSED FOR USE TO ENSURE BOTH; SAFE (NO/MINIMUM SIDE EFFECTS / TOXIC EFFECTS ETC.) EFFICACIOUS (DO WHAT THEY INTENDED FOR – PRODUCE AN ACCEPTABLE LEVEL OF IMMUNITY)
DIFFERENT PHASES – COSTS UP TO £600 MILLION PER VACCINE!
ANSWER THESE QUESTIONS WHILST WATCHING THE VIDEO CLIP What is a placebo? This is sometimes given to the control group. It looks exactly like the real treatment but has no drug (has no active ingredient) in it. Allows a valid comparison to assess effect of new treatment What is a double blind trial? Neither the patient of the doctor know whether the patient is in the control group or not (blind – where patient not know but doctor does). Ensures the elimination of bias (irrational preference / prejudice) How do they maintain a fair test during a clinical drug trial? Standardize as many factors eg. diet etc. Complete ALL data.
Randomisation Again eliminates bias by ensuring gender / age / ethnic groups and other factors that may affect the outcome of a trial are not taken into account as groups for placebo controlled / vaccine are done by a computer. Experimental Error A computer will also ensure that both groups will be comparatively similar in their composition (number of males / age of patients etc.) Large sample size also helps remove experimental error alongside helping statistical analysis to ensure efficacious of the vaccine. OTHER FACTORS TO MAKE CLINICAL TRIALS AS FAIR AS POSSIBLE.....
LICENSED! STATISTICALLY THE DATA WILL BE COMPARED AND ENSURE THERE IS A DIFFERENCE FOR THE GROUPS THE VACCINE WILL BE ISSUED A LICENSE FOR USE (USUALLY CONTINENTS NEED TO DO THEIR OWN TRIALS) MASS USE!
5 FROM 3 - VACCINATIONS EACH TABLE TO ANSWER THESE QUESTIONS; MINIMUM MUST GAIN AT LEAST 3 MARKS POTENTIAL TO GET FULL 5 MARKS What is a vaccine?What do vaccines contain? What steps in a vaccine clinical trial ensure safety and efficacy? Alongside immunisation what other control measures are there for preventing pandemics?
5 FROM 3 - VACCINATIONS EACH TABLE TO ANSWER THESE QUESTIONS; MINIMUM MUST GAIN AT LEAST 3 MARKS POTENTIAL TO GET FULL 5 MARKS What is a vaccine? Contains antigens and immune system responds Memory cells and antibodies Rapid destruction before onset of symptoms Extra: explaining the 4 types of immunity, boosters, What do vaccines contain? Attenuated/weakened pathogen Part of pathogen / antigens Inactivated toxins Dead pathogen Extra: adjuvant / boosters / example of vaccine type What steps in a vaccine clinical trial ensure safety and efficacy? Double blind trial Placebo Randomised trial Large sample size for statistical analysis / similar make up of each group for comparison and minimise experimental error Alongside immunisation what other control measures are there for preventing pandemics? Control transmission (quarantine / antisepsis etc.) Controlling Vectors Individual/community responsibility Extra: samples of individual or community regulation
REVIEW MATCH UP THE DEFINITIONS WITH THE KEY WORDS
SUMMARY SLIDE VACCINES ACTIVE IMMUNITY CAN BE DEVELOPED BY VACCINATION WITH ANTIGENS FROM INFECTIOUS PATHOGENS. ANTIGENS FROM INFECTIOUS PATHOGENS, USUALLY MIXED WITH AN ADJUVANT TO ENHANCE THE IMMUNE RESPONSE, INCLUDE INACTIVATED PATHOGEN TOXINS, DEAD PATHOGENS, PARTS OF PATHOGENS AND WEAKENED PATHOGENS. THESE AGENTS INDUCE A PRIMARY IMMUNE RESPONSE AND IMMUNOLOGICAL MEMORY IN THE INDIVIDUAL BUT NOT DISEASE SYMPTOMS.
SUMMARY SLIDE VACCINES CLINICAL TRIALS VACCINES ARE SUBJECTED TO CLINICAL TRIALS IN THE SAME WAY AS OTHER PHARMACEUTICAL MEDICINES TO ESTABLISH THEIR SAFETY AND EFFICACY BEFORE BEING LICENSED FOR USE. CLINICAL TRIALS USE RANDOMISED, DOUBLE-BLIND, PLACEBO-CONTROLLED PROTOCOLS. SUBJECTS ARE SPLIT INTO GROUPS IN A RANDOMISED WAY IN WHICH NEITHER THE SUBJECTS NOR THE RESEARCHERS KNOW WHICH GROUP THEY ARE IN TO ELIMINATE BIAS. ONE GROUP OF SUBJECTS RECEIVES THE VACCINE, WHILE THE SECOND GROUP RECEIVES A PLACEBO CONTROL TO ENSURE VALID COMPARISONS. AT THE END OF THE TRIAL, RESULTS FROM THE TWO GROUPS, WHICH MUST BE OF A SUITABLE SIZE TO REDUCE THE MAGNITUDE OF EXPERIMENTAL ERROR ARE COMPARED TO DETERMINE WHETHER THERE ARE ANY STATISTICALLY SIGNIFICANT DIFFERENCES BETWEEN THE GROUPS.