Immunisation and Prophylaxis Flashcards
Define immunisation
Induction of immunity to a specific infectious disease
Define prophylaxis
Prevention of disease
Break down immunity into its different categories
Immunity - innate and acquired
Acquired - natural and artificial
Natural - passive (maternal) & active (dx)
Artificial - passive (Ig) & active (vaccination)
Where is all the information about vaccines held?
Green book
BNF
How do vaccines work?
Stimulate active immunity and provide immunological memory (so if you were to encounter the pathogen you’d have a rapid response)
What are the different types of vaccines?
Live attenuated
Inactivated
Subunits of micro-organism
Detoxified exotoxin
What are live attenuated vaccines?
Live micro-organisms that have been modified to make them less deadly/closely related microorganisms
Provoked better immune response but not suitable for immunocompromised
Give examples of live attenuated vaccines
Yellow fever, MMR, BCG, VV, smallpox, typhoid, polio, rotavirus
What are inactivate vaccines?
Whole micro-organism has been killed with radiation, chemicals, antibiotics
Cannot become infected from this
Give examples of inactivated vaccines
Polio, hep A, cholera, Japanese encephalitis, tick-borne encephalitis, influenza
What are detoxified exotoxin vaccines?
Mix toxin with formula to make it inactive
Give examples of detoxified exotoxin vaccines?
Tetanus, diptheria
What are the different types of subunit micro-organisms?
A. purified microbial products
B. recombinant DNA
Give examples of recombinant DNA vaccines
Hep B, Hib, pertussis, MenC, pneumococcus, typhoid, anthrax
What are IgM?
Ab released after immediate exposure to a pathogen
Temporary - only stays in body for a while
Indicator of current infection
What are IgG?
Responsible for long lived immunity and memory
Indicator of previous infection
How many doses of killed vaccines do you need?
Often 2-3 as first few may not be adequate in producing an immune response
How many doses of live vaccines do you need?
Often only req. single dose as they are more immunogenic
What is in the 6 in 1 vaccine Infranrix hexa?
D - purified diptheria toxin T - purified tetanus toxin aP - purified Bordetella pertussis IPV - inactive polio virus Hib - purified component of Hib HBV - hepB rDNA
Define herd immunity
Immunity that occurs when a significant percentage of population are vaccinated (90-95%)
Really important to protect those who are too ill/young to be vaccinated
What patients are offered BCG?
Infants 0-12m from area in UK with/parents/grandparents from country with incidence of 40/100, 000 or more of TB
New immigrants from high prevalence countries
Contacts <35y of resp TB
Healthcare workers
Who is offered influenza vaccine?
>65y Nursing home resident Immunodeficiency/suppression Asplenia/hyposplenism Chronic liver/renal/heart/lung dx DM Coeliac disease Pregnant woman
What are the two pneumococcal vaccines?
13 serotype: Prevenar13 - 3 doses, part of childhood immunisation schedule
23 serotype: pneumovax II (single dose) - for certain indications
What indicates the 23 serotype pneumonoccal polysaccharide vaccination?
Immunodeficiency/suppression Asplenia/hyposplenism Sickle cell dx Chronic liver/renal/cardiac/lung disease DM Coeliac dx
Who are offered HepB vaccination?
All new born children from 2018 (0, 1, 2 m & 1y)
Healthcare workers, PWID, MSM, prisoners, ch. liver/kidney disease
Who is the VZV vaccine offered to?
Immunosupression, e.g. cancer/organ tx
Children if at high risk of severe VZV
Healthcare workers (if sero-neg)
What kind of vaccine is VZV and when is it given/
Live attenuated
2 doses - 4-8wks apart
What is a lifethreatening complication of VZV?
Pneumonitis
Who is the shingles vaccine given to?
All elderly patients (70-80)
What is shingles?
Dermatomal rash with painful blistering assoc with reactivation of VZV (virus remains dormant in dorsal root ganglia)
When should human normal Ig be given?
Immunodeficiencies, some autoimmune dx, e.g. myasthenia gravis
What does human normal Ig contain?
Hep A, rubella, measles
What are some disease specific Ig you can give post-exposure?
Hep B Ig Rabies Ig Tetanus antitoxin Ig Varicella Ig Diphtheria anti-toxin Ig Botulinium anti-toxin Ig
What is involved in risk assessment of a traveller?
Health of traveller Prev. immunisation/prophylaxis Area to be visited Duration of visit Accommodation Activities Remote areas Recent outbreaks
What general travel advice should you give?
Avoid sunburn, sunstroke, altitude sickness Care with food/water Handwashing Road traffic accidents Safer sex Mosquitos - bed nets, sprays, cover up
What are some common immunisations for travellers?
Yellow fever, tetanus, polio, hep B, cholera, typhoid
When should you give men ACWY vaccine?
If going to certain areas with high incidence of meningococcus, e.g. Saharan Africa
When should you give rabies vaccine?
Working with bats/dogs/likely to be bitten
What is the ABCD of malaria prevention?
Awareness of risk
Bite prevention - cover up at dusk/dawn/insect repellent, DEET, mosquito nets
Chemoprophylaxis
Diagnosis and Rx
What chemoprophylaxis options are there for malaria prevention?
Malarone (proquanil and atovaquone) daily
Doxycycline daily (>12 only, photosensitivity)
Mefloquine weekly
Chloroquine weekly & proquanil daily
What are the side effects of mefloquine?
Psychosis, nightmares
What type of malaria does chloroquine and proquanil protect against?
Vivax, ovale, malariae only
What malaria advice is given to travellers on return?
Any illness occurring within 1 year, esp 3 months of return may be malaria
