Immunisation Flashcards
Herd immunity
Idea of population based benefit of vaccination where there is reduced disease in vaccinated and unvaccinated people
Types of things in vaccines and immunity associated
Protein antigens- T cel dependent antibodies
Polysaccharide antigens- T cell independent antibodies
Live viral vaccines- antibodies, CD8 cytotoxic T cells
Classification of vaccines
____ ______: Live viruses or bacteria
_____ vaccines: whole viruses, bacteria or fractions; ____ based(toxoids, subunit or subvirion); ______ based (pure cell wall); _____ ______ (cell wall polysaccharide linked to prot
Live attenuated: Live virusesor bacteria
Inactivated vaccines: whole viruses, bacteria or fractions; protein based(toxoids, subunit or subvirion); polysaccharide based (pure cell wall); conjugate polysaccharide (cell wall polysaccharide linked to protein
Live attenuated vaccines
\_\_\_ virus/bacteria in lab. \_\_\_\_ and produce immunity, but not \_\_\_\_\_ Viral: \_\_\_\_, varicella, oral polio Bacterial: BCG (TB), oral typhoid Reassorted: rotavirus
Problems in ________ people
Modify virus/bacteria in lab. Replicate and produce immunity, but not illness Viral: MMR, varicella, oral polio Bacterial: BCG (TB), oral typhoid Reassorted: rotavirus
Problems in immunocompromised people
Inactivated vaccines
Killed ____ vaccines
Not _____ immunity with one dose
Repeat needed
Whole viral: _____, injected polio, rabies, hepA
Whole bacterial: _____, typhoid, cholera
Fractional: subunits (____, influenza, acellular pertussis); toxoids (_____, ____)
Killed antigen vaccines
Not lifelong immunity with one dose
Repeat needed
Whole viral: influenza, injected polio, rabies, hepA
Whole bacterial: pertussis, typhoid, cholera
Fractional: subunits (hepB, influenza, acellular pertussis); toxoids (diptheria, tetanus)
Recombinant vaccines currently being used
HepB vaccine: Segment of hepatitis B gene into yeast expression system
Live attenuated influenza vaccine: made to replicate in nasopharynx, but not lungs
Childhood vaccines and times
D T aP IPV HepB HiB- are all component antigen vaccines, given 6 weeks, 3 mths, 5 mths and 4 years
MMR: live virus vaccines give at 15mths and 4 years (twice to be sure because of potential danger if immunocompromised)
Tetanus- clostridium tetani
____, gram _____ bacillus, penicillin sensitive
Spores everywhere particularly ___, ____
Easy to introduce with deep dirty wounds
Symptoms after about 10 days, causing muscular rigidity caused by tetanospasmin toxin
most at risk if age above ___ due to waned ____
Anaerobic, gram positive bacillus, penicillin sensitive
Spores everywhere particularly soil, manure
Easy to introduce with deep dirty wounds
Symptoms after about 10 days, causing muscular rigidity caused by tetanospasmin toxin
most at risk if age above 60 due to waned immunity
Neonatal tetanus key points
Transferred to baby if mother is afflicted
If mother not immunised no passive immunity as no IgG in babies system
Can give human tetanus Ig to help, to lessen severity of disease
Advantages and disadvantages of passive immunity
A: Immediate protection
D: no long term; risk of transmission of other disease from donor, expensive, serum sickness from injection of someone else’s serum
Tetanus prophylaxis key points
Essentially if time since last tetanus dose (assuming more than 3) is 50-10 years or more (assuming a tetanus prone wounds) give a booster.
Only give TIG for less than 3 doses and tetanus prone wound
Bordetella pertussis
Gram ____ ____
Causes ___ ____
Highest mortality in ___ year of life, among 10 most common cause of death from infectious disease
Very infectious/_____, by sneezing
Clinical manifestation:
- ____: runny nose, malaise, conjunctival injection 1-2 weeks
- _____ phase 1 -10 weeks, short expiratory bursts, then inspiratory gasp and high pitched whoop
- _____ phase of weeks to months
Complications: secondary bacterial infection, encephalopathy
Treatment: _____ may shorten illness and reduce infectivity if started early
Gram negative bacillus
Causes whooping cough
Highest mortality in first year of life, 10 most common cause of death from infectious disease
Very infectious/contagious by sneezing
Clinical manifestation:
- Catarrhal: runny nose, malaise, conjunctival injection 1-2 weeks
- Paroxysmal phase 1 -10 weeks, short expiratory bursts, then inspiratory gasp and high pitched whoop
- Convalescent phase of weeks to months
Complications: secondary bacterial infection, encephalopathy
Treatment: Erythromycin may shorten illness and reduce infectivity if started early
Pertussis vaccine
Adults?
Whole cell vaccine: Had a lot of side effects, so was stopped
Acellular vaccine: 3 dose primary schedule and 2 booster doses (boostrix) (4 and 11). Problem with follow up doses, only about 50% end up with final dose.
Adults are encouraged to get booster vaccination as susceptible adults can act as a reservoir of the bacteria and pass on to children
Poliomyelitis from polio virus and he vaccines
Destroys LMN’s resulting in ____
Children under 5. Respiratory paralysis and failure sometimes
Live oral: ____ used where polio is endemic
____ polio vaccine: 99% effective with 3 course dose, most countries have changed for OPV to IPV. NZ in 2002
Destroys LMN’s resulting in paralysis
Children under 5. Respiratory paralysis and failure sometimes.
Live oral: OPV used where polio is endemic
Inactivated polio vaccine: 99% effective with 3 course dose, most countries have changed for OPV to IPV. NZ in 2002
