Diseases Flashcards
(37 cards)
Duration of yellow fever vaccine
Exemptions
Precautions
Lifelong
Exemptions: age
Yellow fever:
- Genus
- Incubation period
- Infectious period
- Flavivirus
- 3-6 days
- Just before fever for 3-5 days
Measles
- Incubation period
- Reproductive rate
- Infectious period
- Timing of rash
- 7 - 18 days (usually 10 days)
- 15-18
- 1 day prior to prodromal illness to 4 days after rash appearance
- rash appears day 3-4 and lasts 4-7 days
Listeria
- Incubation period
- Period of communicability
- Risk factors
- Source
- Diagnosis
- 3-70 days (median 3 weeks)
- 7-10 days (mother to baby)
- Pregnant women/fetuses, newborns, immunosuppression
- contaminated food particularly cheese, ready-to-eat meals and salads, deli meats, pate
- Usually blood cultures or another sterile site (e.g. CSF)
Define a community outbreak of IMD
3 or more confirmed or probable cases of IMD with no direct epidemiologic link within a defined area within 3 months with a primary attack rate of 10 per 100 000
What changes in epidemiology of meningococcal disease are suggestive of an outbreak? (3)
- increased rate of disease (or increase in number in small populations)
- clustering of cases in an age group or a shift in the age distribution of cases
- phenotyphic or genetic similarity among cases
Define an organisation-based outbreak of IMD
2 or more probable or confirmed cases within 4 weeks among an organisation e.g. high school but no close contact with each other
What are the national case definitions for measles:
- Confirmed case
- Probable case
- Confirmed case = lab definitive evidence, or
clinical and epi evidence - Probable case = lab suggestive evidence and clinical evidence.
clinical evidence = generalised maculopapular rash for 3 or more days + fever>38 at time of rash onset + [cough or coryza or conjunctivitis or koplik spots]
**epi evidence = contact with an infectious/suspected case
**lab-suggestive evidence: IgM detected by a non-reference lab (except if recently had measles vaccine)
Measles lab tests:
<3 weeks
>3 weeks
3 weeks: nasopharyngeal swab and urine for NAT and culture. Blood for serology and WGS
>3 weeks: serology
Measles
- what are the r/f for severe disease?
- what are the potential complications?
- what is the case fatality?
- R/F: young children, malnutrition, vitamin A deficiency
- haemorrhagic rash, protein-losing enteropathy, otitis media(6%), severe skin infections, pneumonia (9%)
- exacerbation of vitamin A deficiency -> blindness
Subacute sclerosing panencephalitis (1/100 000) several years after infection - Case fatality 3-5% in developing countries
What is the incubation period of hepatitis A?
15-50 days (commonly 28-30)
What is the infectious period of hepatitis A?
from a few days prior to illness to a few days after jaundice
Case definition for hepatitis A
- Confirmed case
- Probable case
- Confirmed = Lab-definitive evidence (IgM or NAT)
2. Probable = Clinical and epi evidence
- For hepatitis A contacts who should you consider post-exposure prophylaxis (vaccine or Ig)>
- which groups should receive NHIG?
- -household or sexual contacts
- if case in childcare centre -> contacts
- if case in food handler -> contacts who ate food prepared or other food handlers
Use NHIG for
-
What is the incubation period of IMD?
1-7 days (up to 10)
What are the case definitions for IMD?
confirmed and probable
Confirmed case = lab definitive evidence (isolation of N. meningitidis from a sterile site, or NAT)
OR lab-suggestive (gram neg diplococci or IgM) and clinical evidence (clinically compatible illness)
Probable case = clinical evidence
What are the main considerations during an outbreak of IMD?
- Establish a team, lab-communication and comms
- Confirm the diagnosis and serotype
- Active surveillance: age-specific or region-specific rates
- Information provision early: public (media releases, press conference), HCW, prepare for increase in calls
- Manage contacts: clearance ABx
- Consider vaccination depending on strain and size of organisation or community
Who are the at-risk contacts and other groups for meningococcal disease?
contacts: -household or other intimate -childcare/school/uni -HCW - lab workers Other: -Immunosuppressed -ATSI -crowding/smoke exposure
What is the incubation period for Legionella?
Legionnaires disease: 2-10 days (usually 5-6)
Pontiac fever: 5-72 hous (usually 1-2 days)
What are the diagnostic tests for Legionella?
LP antigen in urine (in Tas just LP1)
4-fold rise in titre of LP of 3-6 weeks
Culture
When do you start investigating a cluster of Legionnaire’s disease?
2 or more cases with a common exposure (within 100m) over a 3 month period
What are the most likely potential sources of a legionella outbreak?
Aerosolised water (e.g. veg section of supermarket)
- car washes
- cooling towers (e.g. shopping centres, clubs)
- spas
- fountains
- warm water systems
What is the incubation period for zika virus?
What is the typical duration of illness for Zika virus?
3-12 days
duration: 4-7 days
What is the incubation period for pertussis?
4-21 days (usually 7-10)