Oral Presentation 20th Lancefield International Symposium on Streptococci and Streptococcal Diseases 2017

  Robust Evidence Finally Available for Prevention of First Presentation Acute Rheumatic Fever in a Community Setting :   a school based intervention. (#34)

philippa anderson 1 , melissa kerdemelidis 2 , elizabeth farrell 3 , sue crengle mahi 4 , teuila percival 5 , david jansen 6 , joanna stewart 7 , Diana Lennon
  1. population health, counties manukau district health board, auckland, new zealand
  2. funding and planning, canterbury district health board, christchurch, canterbury, new zealand
  3. kidsfirst public health nursing, counties manukau district health board , auckland, new zealad
  4. invercargill medical centre, invercargill, southland, new zealand
  5. pacific health studies, university of auckland, auckland, new zealand
  6. national hauora coalition, auckland, new zealand
  7. dept of epidemiology and biostatistics, university of auckland, auckland, new zealand

BACKGROUND: Robust evidence is lacking for community initiatives to prevent first presentation acute rheumatic fever (ARF) by group A streptococcal (GAS) pharyngitis treatment. Significant NZ government investment centred on school clinics.

METHODS: We measured the effect of introducing a sore throat clinic program on first presentation ARF into 61 year 1-8 schools with students aged 5-13years ( population ~ 25 000 ). in Auckland, NZ. The study period was 2010-2016. A generalised linear mixed model investigated ARF rate changes before and after the staggered introduction of school clinics. Nurses/ lay workers treated culture-proven GAS sore throats (including siblings) with 10 days amoxicillin.  ARF cases were identified from a population-based secondary prophylaxis register. Annual pharyngeal GAS prevalence was assessed in a subset.  

RESULTS: ARF rates (5-13 years) dropped from 88 (95% CI 79, 111)/100,000 pre clinics to 37 (95% CI 15, 83)/100,000 after 2 years of clinics, a 58% reduction.

No change in rate was demonstrated prior to the introduction of clinics (p=0.88, incidence risk ratio (IRR) for a one year change 0.98 (95% CI 0.63, 1.52)) but there was a significant decrease of first presentation ARF rates over time following the introduction of the sore throat program (p=0.008, IRR 0.61 (95% CI 0.43, 0.88)).

Pharyngeal GAS cross sectional prevalence fell from 22.4% (16.5, 30.5) pre intervention to   11.9% (8.6, 16.5) and 11.4% (8.2, 15.7) one and two years later (p=0.005)

CONCLUSIONS: ARF declined significantly following school-based GAS pharyngitis management using oral amoxicillin paralleled by a decline in pharyngeal GAS prevalence.