Table 2.

Comparative symptom severity for different strains of influenza and non-influenza viruses and different age groups

	Fever	Feverish	Headache	Muscle ache	Sore throat	Cough	Runny nose	Sneeze	Blocked nose
A(H1N1)pdm09* (n=102)	1	1	1	1	1	1	1	1	1
H3N2(n=35)	1·09(0·61–1·95); 0·774	2·22(1·33–3·71); 0·002	2·72(1·60–4·63); <0·001	4·15(2·36–7·27); <0·001	1·51(0·90–2·54); 0·118	1·34(0·82–2·18); 0·245	3·18(2·12–4·77); <0·001	2·95(1·88–4·62); <0·001	2·39(1·46–3·93); 0·001
H1N1(n=10)	0·27(0·09–0·87); 0·027	0·59(0·28–1·25); 0·172	1·53(1·83–2·81); 0·173	1·23(0·49–3·08); 0·653	2·29(1·13–4·60); 0·020	0·85(0·47–1·54); 0·584	2·26(1·24–4·10); 0·007	1·74(1·00–3·02); 0·05	1·76(0·96–3·23); 0·068
Influenza B (n=35)	1·56(0·87–2·80); 0·134	1·94(1·08–3·47); 0·026	1·27(0·72–2·25); 0·411	1·79(0·91–3·52); 0·094	1·32(0·73–2·37); 0·694	0·69(0·35–1·37); 0·290	1·01(0·59–1·72); 0·972	1·0(0·56–1·78); 0·990	2·02(1·14–3·58); 0·017
Non-influenza (n=385)	0·34(0·22–0·53); <0·001	0·51(0·36–0·72); <0·001	1·02(0·74–1·41); 0·905	0·66(0·44–0·98); 0·040	1·07(0·76–1·50); 0·694	0·56(0·40–0·77); <0·001	1·95(1·45–2·62); <0·001	1·50(1·11–2·05); 0·009	1·93(1·14–3·58); 0·017
0–15 years* (n=189)	1	1	1	1	1	1	1	1	1
16–44 years (n=147)	0·25(0·15–0·41); <0·001	0·95(0·66–1·39); 0·803	1·32(0·95–1·85); 0·098	1·48(0·98–2·22); 0·06	1·60(1·16–2·20); 0·005	0·68(0·50–0·94); 0·019	0·91(0·68–1·20); 0·0503	1·28(0·96–1·70); 0·09	1·18(0·85–1·63); 0·323
45–64 years (n=195)	0·31(0·20–0·50); <0·001	1·55(1·11–2·18); 0·010	1·22(0·89–1·67); 0·219	1·75(1·18–2·59); 0·005	1·35(0·99–1·87); 0·056	0·81(0·60–1·08); 1·045	0·82(0·63–1·07); 0·148	1·15(0·87–1·52); 0·324	0·97(0·71–1·32); 0·826
≥65 years (n=70)	0·135(0·07–0·28); <0·001	1·09(0·67–1·78); 0·726	0·97(0·64–1·47); 0·888	1·67(0·94–2·97); 0·08	1·12(0·75–1·68); 0·569	1·22(0·84–1·76); 0·0294	1·08(0·74–1·58); 0·678	2·10(1·36–2·96); <0·001	0·88(0·54–1·42); 0·595

Data are adjusted OR (95% CI); p value (across the categories of the symptom severity scale, assuming proportional odds). Numbers in the left-hand column refer to the number of PCR-confirmed cases across all years with information on daily symptoms. ORs are mutually adjusted for age and strain type. OR=odds ratio.

^*Baseline group for comparisons.