Public Health Flashcards
What is bias?
- The results of a study do not represent the truth
- inherent limitation in design/conduct
- several tools to rate risk of bias in RCTs
What is imprecision?
- Focuses on 95% CI around best estimate of absolute effect
- Certainty lower if clinical decision likely to be different if true effects at upper end of CI
What is indirectness?
- Certainty highest when studies directly compare interventions of interest in relevant populations
- Report outcome critical for decision making
What is publication bias?
- missing evidence
- More common in:
-> observational data
-> commercial studies
What is inconsistency?
- Certainty of evidence highest when several studies show a consistent effect
What is primary vaccine failure?
Person doesn’t develop immunity from vaccine
What is a secondary vaccine failure?
Initially responds but protection wanes over time.
What are the symptoms of tetanus?
- Clostridium tetani bacteria
- toxins cause painful muscle contraction
What bacteria causes pertussis and the symptoms?
- Bordetella pertussis bacteria
- whooping cough
What causes polio and its symptoms?
- poliovirus
- bad water
- attacks nerves, then causes muscle wasting
What causes Haemophilus influenza type B and its symptoms?
- haemophilus influenza bacteria
- acute epiglottis –> swells up stopping you form breathing
What is meningococcal disease caused by and symptoms?
- Neisseria meningitides bacteria
- Meningococcal sepsis
What is your legal obligation as a doctor?
- to notify on infectious diseases
- to stop outbreak of disease
Why are these diseases notifiable?
- very scary
- horrible complications
- very infectious
- vaccine preventable
- need specific control measures
What is the role of surveillance with infectious diseases?
- Detection of any changes in a disease
- outbreak detection
- early warning
- forecasting - Track changes in disease
- extent and severity of disease
- risk factors - Allows development of interventions targeted at vulnerable groups
How do we protect the community?
- Investigate: contact tracing, partner notification, lookback exercises, etc…
- Identify and protect vulnerable persons: e.g. chemoprophylaxis, immunisation, isolation
- Exclude high risk persons or from high risk settings
- Educate, inform, raise awareness, health promotion
- Coordinate multi-agency responses
What are the 3 steps on route of disease transmission?
- Source
- pathway
- receptor
What to think about when someone is infected with scarlet fever?
- risk settings e.g. schools
- co-infections e.g. chickenpox
What factors to think about when someone is infected with typhoid fever?
- risk factors e.g. travel
- risk groups e.g. food handlers, health & care staff, young children, hygiene
What factors to think about when someone has Hep B?
- Risk factors e.g. travel, medical procedures, infected mothers, blood products
- Risk groups e.g. sex workers
What vaccines do you get at 8 weeks old?
- 6in1
- diptheria
- tetanus
- pertussis
- polio
- haemophilus influenza type b
- hep B - Meningococcal group B
- Rotavirus gastroenteritis
What vaccines are given at 12 weeks old?
- 6in1
- pneumococcal
- rotavirus
What vaccines are given at 12 weeks old?
- 6in1
- pneumococcal
- rotavirus
What vaccines are given at 16 weeks old?
- 6in1
- Men B
What vaccines are given at 1yrs old?
- Haemophilus Influenza type B (Hib) & Men C
- pneumococcal
- measles, mumps and rubella
- Men B
What vaccine is is given at 3yrs 4 months?
- 4 in 1 –> diphtheria, tetanus, pertussis, polio
- measles, mumps, rubella
What vaccine is given at 12/13 yrs old?
Human papillomavirus (HPV)
What vaccine is given at 14 yrs old?
- Tetanus, diphtheria and polio
- Men ACWY
What are the steps in a virus spreading in the population?
- sporadic case
- cluster
- outbreak
- epidemic
- pandemic
- endemic
What are some public health countermeasures?
- Hygiene
- social distancing
- isolation/quarantine
- personal protective equipment
- treatment vs prevention
- chemoprophylaxis
- vaccination
How many genera of influenza are there?
A, B and C
Why does influenza change very year?
- gene reassortment
- gene swapping (between human and avian flu virus)
- no proof reading mechanism so prone to mutation
- minor antigenic variation (antigenic drift)
How in influenza transmitted?
- aerosol (cough & sneezes)
- also hand to hand contact
Who is more likely to be affected by the flu?
Mortality risk higher in persons with underlying medical conditions:
- Chronic cardiac and pulmonary diseases
- Old age
- Chronic metabolic diseases
- Chronic renal disease
- Immunosuppressed
What are the symptoms of influenza?
- upper and/or resp tract symptoms
- fever
- headache
- myalgia
- weakness
bacterial pneumonia
What is avian influenza?
- avian pathogen can pass from birds to humans
- due to close proximity of poultry and people
How do we control avian flu?
Cull affected birds
Biosecurity and quarantine
Disinfecting farms
Control poultry movement
Vaccinate workers – seasonal influenza vaccine
Antivirals for poultry workers
Personal Protective Equipment (PPE)
Try to reduce chance of co-infection
What is pandemic flu?
- virus mutates markedly (antigenic shift)
- large proportion of population is susceptible
- virus usually jumps from one species to another
- high morbidity
- excess mortality
- social disruption
- economic disruption