ARF risk following GAS positive skin swab* | ARF risk following GAS negative skin swab†* | RR | |||||
Total ARF following GAS positive swab | Total GAS positive swabs | ARF per 100 000 GAS positive swabs | Total ARF following GAS negative swab | Total GAS negative swabs | ARF per 100 000 GAS negative swabs | Risk of ARF following GAS-positive swab vs GAS-negative swab RR(95% CI) | |
Risk of initial ARF hospitalisation during specific time window (total population) | |||||||
ARF 1–7 days of swab | 2 | 54 217 | 3.7 | 0 | 380 755 | – | – |
ARF 8–90 days of swab | 11 | 54 217 | 20.3 | 5 | 380 755 | 1.3 | 15.45 (5.37 to 44.48) |
ARF 1–365 days of swab | 24 | 54 217 | 44.3 | 27 | 380 755 | 7.5 | 6.24 (3.60 to 10.82) |
Risk of initial ARF hospitalisation, restricted to 8–90 days | |||||||
Age group (years) (8–90 days following swab) | |||||||
<5 | 0 | 11 894 | – | 0 | 41 158 | – | – |
5–9 | 1 | 10 815 | 9.2 | 2 | 21 721 | 9.2 | 1.00 (0.09 to 11.08) |
10–14 | 6 | 6334 | 94.7 | 2 | 19 736 | 10.1 | 9.36 (1.89 to 46.36) |
15–19 | 3 | 4755 | 63.1 | 1 | 21 262 | 4.7 | 13.42 (1.40 to 129.06) |
20–29 | 1 | 6290 | 15.9 | 0 | 37 139 | – | – |
>29 | 0 | 14 129 | – | 0 | 239 735 | – | – |
Gender (8–90 days following a swab) | |||||||
Male | 7 | 29 448 | 23.8 | 2 | 179 199 | 1.1 | 21.30 (4.42 to 102.55) |
Female | 4 | 24 763 | 16.2 | 3 | 201 505 | 1.5 | 10.85 (2.43 to 48.47) |
Prioritised ethnicity (8–90 days following a swab) | |||||||
Māori | 3 | 13 335 | 22.5 | 1 | 37 023 | 2.7 | 8.33 (0.87 to 80.10) |
Pacific | 7 | 25 148 | 27.8 | 4 | 62 401 | 6.5 | 4.27 (1.25 to 14.60) |
Māori and Pacific | 10 | 38 483 | 26.0 | 5 | 98 424 | 5.1 | 5.11 (1.75 to 14.97) |
Asian | 1 | 2375 | 42.1 | 0 | 38 533 | – | – |
NZ European/Other | 0 | 13 359 | – | 0 | 243 794 | – | – |
Socio-economic deprivation (NZ Dep quintile) (8–90 days following a swab) | |||||||
1 (low deprivation) | 0 | 4510 | – | 0 | 82 065 | – | – |
2 | 1 | 5753 | 17.4 | 0 | 81 027 | – | – |
3 | 2 | 6183 | 32.3 | 0 | 70 165 | – | – |
4 | 2 | 8543 | 23.4 | 1 | 51 142 | 2.0 | 11.97 (1.09 to 132.02) |
5 (high deprivation) | 6 | 29 228 | 23.6 | 5 | 95 456 | 5.2 | 4.90 (1.38 to 17.36) |
Risk of initial ARF hospitalisation, during 8–90 day window restricted to Māori and Pacific aged 10–19 years | |||||||
Gender (8–90 days following a swab) | |||||||
Male | 6 | 4426 | 135.6 | 2 | 8983 | 22.3 | 6.10 (1.23 to 30.15) |
Female | 2 | 4005 | 49.9 | 1 | 8037 | 12.4 | 4.01 (0.36 to 44.24) |
Prioritised ethnicity (8–90 days following a swab) | |||||||
Māori | 2 | 2886 | 69.3 | 1 | 5698 | 17.6 | 3.95 (0.36 to 43.60) |
Pacific | 6 | 5546 | 108.2 | 2 | 11 324 | 17.7 | 6.12 (1.24 to 30.39) |
Socio-economic deprivation (NZ Dep quintile) (8–90 days following a swab) | |||||||
1 (low deprivation) | 0 | 202 | – | 0 | 781 | – | – |
2 | 0 | 515 | – | 0 | 1335 | – | – |
3 | 1 | 742 | 134.8 | 0 | 1702 | – | – |
4 | 2 | 1351 | 148.0 | 1 | 2924 | 34.2 | 4.34 (0.39 to 47.70) |
5 (high deprivation) | 5 | 5622 | 88.9 | 2 | 10 283 | 19.4 | 4.58 (0.89 to 23.59) |
Total | 8 | 8432 | 94.9 | 3 | 17 025 | 17.6 | 5.39 (1.43 to 20.32) |
Antibiotics dispensed (within 7 days of swab among Māori and Pacific People aged 5–19 years) | |||||||
Antibiotics | 3 | 6906 | 43.4 | 2 | 9278 | 21.6 | 2.01 (0.34 to 12.05) |
No antibiotics | 6 | 9477 | 63.4 | 3 | 16 529 | 18.1 | 3.49 (0.87 to 13.94) |
*GAS-positive throat swabs were excluded±14 days of all skin swabs.
†GAS-negative swabs were also culture negative for group C/G streptococci.
ARF, acute rheumatic fever; GAS, group A streptococcus; RR, risk ratio.