Table 2.
Crude incidence rates as episodes per child-year for LRTI, hospitalised LRTI, RSV LRTI, and hospitalised RSV LRTI over the first 2 years of life in the DCHS
| LRTI (n=851 episodes) | Hospitalised LRTI (n=169 episodes) | RSV LRTI (n=164 episodes) | Hospitalised RSV LRTI (n=54 episodes) | ||
|---|---|---|---|---|---|
| All | 0·41 (0·38–0·43) | 0·08 (0·07–0·09) | 0·08 (0·07–0·09) | 0·03 (0·02–0·03) | |
| Age group | |||||
| 0–6 months | 0·72 (0·65–0·79) | 0·17 (0·14–0·21) | 0·15 (0·12–0·19) | 0·07 (0·05–0·10) | |
| 0–1 years | 0·54 (0·50–0·59) | 0·13 (0·11–0·15) | 0·12 (0·10–0·14) | 0·05 (0·03–0·06) | |
| 1–2 years | 0·28 (0·25–0·31) | 0·04 (0·03–0·05) | 0·04 (0·03–0·06) | 0·01 (0·00–0·01) | |
| Season | |||||
| Autumn (Mar–May) | 0·45 (0·40–0·51) | 0·09 (0·06–0·11) | 0·15 (0·12–0·19) | 0·04 (0·03–0·06) | |
| Winter (June-Aug) | 0·52 (0·47–0·59) | 0·13 (0·10–0·16) | 0·15 (0·12–0·19) | 0·06 (0·04–0·08) | |
| Spring (Sept–Nov) | 0·41 (0·36–0·47) | 0·06 (0·04–0·09) | 0·01 (0·00–0·02) | 0·00 (0·00–0·002) | |
| Summer (Dec–Feb) | 0·24 (0·20–0·28) | 0·05 (0·03–0·07) | .. | .. | |
| Severity | |||||
| Hospitalised | 0·08 (0·07–0·09) | .. | 0·03 (0·02–0·03) | .. | |
| Ambulatory | 0·33 (0·30–0·35) | .. | 0·05 (0·04–0·06) | .. | |
Data are episodes per child-year (95% CI). LRTI=lower respiratory tract infection. RSV=respiratory syncytial virus. DCHS=Drakenstein Child Health Study.