Vaccine and Preventable disease

Question 1

Measles

Answer 1

Highly infectious
Prodrome of 2-3 days of conjunctivitis, kopliks spots
-rash 37 days,most unwell. (widespread maculopapular)
-Complications: ear infection, pneumonia, croup

Question 2

Microbial causes of bacterial meningitis

Different pathogens at different ages

Answer 2

Strep pneumoniae (gram +cocci, diplo?)
Neisseria Meningitidis (gram- cocci)
Haemophilus influenza b(gram - bacilli)

Grp B strep and gram negatives in newborns
Viral agents can e.g herpes simplex, enterovirus
TB can cause

Question 3

Reason these microbial agents are so virulent in childhood

Answer 3

Polysaccharide capsules

Children <2 produce a weak antibody response to polysaccharide antigens, and form a poor memory

Question 4

What are conjugate vaccines

Answer 4

Polysaccharides attached to a protein that is an immuno stimulant.
Good for immunogenicity for <2 years of age

Question 5

Haemophilus infuenza type b features

vaccine?

Answer 5

Gram- rod/bacillus
prior to vaccination was serious cause of disease.
Hib vaccine used to induce antibody to PRP on capsule. Are now conjugated

Question 6

Timing of Hib vaccine

Answer 6

6 weeks, 3,5,15 months

Question 7

Strep pneumoniae features

Answer 7

Gram+ coccus
Polysaccharide capsule
90 different serotypes on capsule
In children: most common cause of otitis media, also lungs etc
All ages: bacterial pneumonia most common, meningococci and pnumococci most common cause meningitis

Question 8

Strep pnemoniae vaccine

Answer 8

Not funded, can be used in elderly >65, splenectomy, immunosuppressed, chronic illness
Not useful in younger than 2 because can not recognise antigens.
Conjugated vaccines now used in children to improve

Question 9

Introduction of strep pneumoniae conjugate vaccine benefits

\_\_% efficacy againts \_\_\_\_
\_\_% reduction in clinical \_\_\_\_
\_\_% reduction in X ray confirmed \_\_\_\_\_
Some reduction in \_\_\_\_ \_\_\_\_\_, especially a decrease in antibiotic resistant disease
\_\_\_\_ immunity

Answer 9

97% efficacy againts IPD
11% reduction in clinical pneumonia
33% reduction in X ray confirmed pneumonia
Some reduction in otitis media, especially a decrease in antibiotic resistant disease
Herd immunity

Question 10

Neissearia meningitidis features

Answer 10

Capsule important in virulence
Human only pathogen colonising nasopharynx
transmitted by droplets from colonized people
12 serogroups of PS
A,B and C most common

Question 11

Problem with serogroup B meningococci

Answer 11

Similar structure to sugars on some neural cells, so even if conjugated antibodies against these are deleted during development

Question 12

Vaccination key points

Answer 12

Target of 95% fully immunised at 2 years has been attained by most of the country
Previous economic and socioeconomic inequities gone
New target is vaccination on time (harder for Maori and deprived areas)
Challenges maintaining systems, social media and anti immunisation, shifting priorities