Notifiable diseases and immunisation Flashcards
Passive immunity
Protection provided from the transfer of antibodies from immune individuals.
Most commonly cross-placental transfer of antibodies from mother to child (e.g. measles, pertussis).
Or, via transfusion of blood or blood products including immunoglobulin (e.g. Hep B)
Protection is temporary – usually only a few weeks or months.
Passive immunity provided by injection:
Human immunoglobulin containing antibodies to the target infection.
Temporarily increases person’s antibody level to that specific infection. Protection gained within a few days but lasts only a few weeks.
Human normal immunoglobulin (HNIG) derived from the pooled plasma of donors and contains antibodies to infectious agents that are currently prevalent in the general population.
Used to protect immunocompromised children exposed to measles and of individuals after exposure to hepatitis A.
Specific immunoglobulins available for tetanus, hepatitis B, rabies and varicella zoster.
Active immunisation
Vaccination stimulates immune response and memory to a specific antigen/infection.
Vaccines are made from:
- Inactivated (killed) (e.g. pertussis, inactivated polio)
- Attenuated live organisms (e.g. yellow fever, MMR, polio, BCG)
- Secreted products (e.g. tetanus, diphtheria toxoids)
- The constituents of cell walls/subunits (e.g. Hep B)
- Recombinant components (experimental)
Herd (population) immunity
Herd immunity occurs when a large portion of a community (the herd) becomes immune to a disease. The spread of disease from person to person becomes unlikely when herd immunity is achieved. As a result, the whole community becomes protected — not just those who are immune.
What does vaccine failure mean, and what are the types of vaccine failure?
No vaccine offers 100% protection.
Small proportion of individuals get infected despite vaccination.
Primary vaccine failure – person doesn’t develop immunity from vaccine.
Secondary vaccine failure – initially responds but protection wanes over time.
What are the different immunisation groups?
Routine immunisation schedule: protecting vulnerable and high-risk groups.
Additional vaccines for individuals with underlying medical conditions.
Dipththeria
Corynebacterium diphtheriae.
Bull neck or cutaneous diphtheria.
Tetanus
Clostridium tetani.
Once tetany sets in it cannot be reversed.
Pertussis
Bordetella pertussis.
Whooping cough - distinct sound they make.
Costophrenic recess is very prominent and so are the ribs because they are breathing so hard.
Polio
Poliovirus.
Causes death of neurones = poliomyelitis.
Heamophilus influenzae type B
It is a bacterial infection.
Causes:
- Acute epiglottitis
- Periorbital cellulitis
Meningococcal disease
Caused by Neisseria meningitidis.
Disease:
- Meningococcal sepsis
- Menigitis
Notification of diseases are important because…
Need to prevent further cases.
- Notification
- Contact tracing
- ABx chemoprohylaxis
- Vaccination
Contact tracing
Contact for meningitis is taken to be any person having close contact with a case in the past 7 days.
Close contact includes kissing, sleeping with, spending the night together or spending in excess of eight hours in the same room.
