Volume 19, Number 1—January 2013
Research
Novel Framework for Assessing Epidemiologic Effects of Influenza Epidemics and Pandemics
Table 2
Scaled measures of transmissibility and clinical severity for the refined assessment of pandemic influenza effects
Parameter no. and description | Scale |
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---|---|---|---|---|---|---|---|
1 | 2 | 3 | 4 | 5 | 6 | 7 | |
Transmissibility | |||||||
1. Symptomatic attack rate, community, % | <10 | 11–15 | 16–20 | 21–24 | >25 | ||
2. Symptomatic attack rate, school, % | <20 | 21–25 | 26–30 | 31–35 | >36 | ||
3. Symptomatic attack rate, workplace, % | <10 | 11–15 | 16–20 | 21–24 | >25 | ||
4. Household secondary attack rate, symptomatic, % | <5 | 6–10 | 11–15 | 16–20 | >21 | ||
5. R0: basic reproductive no. | <1.1 | 1.2–1.3 | 1.4–1.5 | 1.6–1.7 | >1.8 | ||
6. Peak % outpatient visits for influenza-like illness |
1–3 |
4–6 |
7–9 |
10–12 |
>13 |
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Clinical severity | |||||||
1. Case-fatality ratio, % | <0.02 | 0.02–0.05 | 0.05–0.1 | 0.1–0.25 | 0.25–0.5 | 0.5–1 | >1 |
2. Case-hospitalization ratio, % | <0.5 | 0.5–0.8 | 0.8–1.5 | 1.5–3 | 3–5 | 5–7 | >7 |
3. Ratio, deaths: hospitalization, % | <3 | 4–6 | 7–9 | 10–12 | 13–15 | 16–18 | >18 |