Table 3. Clinical presentation of influenza patients according to age group and influenza virus type and subtype in the age groups 15–64 years and 65 years or older.

Univariate analysis. The IBVD (Influenza B in Vircases database) study, France, 2003–2004 to 2012–2013.

	15–64 years				65+ years
	B (a)	A (a)	A(H3N2)	A(H1N1)pdm09	B (a)	A (a)	A(H3N2)	A(H1N1)pdm09
	n = 1213	n = 4787	n = 2149	n = 1594	n = 73	n = 195	n = 129	n = 27
Gender ratio (M/F)	0.9	1	0.9	1	0.7	0.8	0.8	1.1
% of patients with 7 symptoms or more	68.4%	68.9%	71.5%	64.9% *	56.2%	53.9%	55.0%	55.6%
Symptoms (%) (b)
Fever	96.6%	96.3%	96.5%	96.2%	97.3%	95.8%	95.3%	92.6%
Asthenia	90.0%	88.4%	88.0%	88.9%	83.6%	80.4%	78.3%	85.2%
Myalgia	89.3%	89.1%	90.0%	87.0%	84.9%	77.3%	75.2%	85.2%
Shivering	82.4%	83.7%	84.7%	80.8%	77.5%	69.4%	69.5%	70.4%
Cephalalgia	81.5%	81.8%	83.1%	78.1% *	73.6%	65.5%	66.7%	55.6%
Cough	90.0%	88.4%	87.2% *	93.1% **	94.4%	89.2%	91.5%	88.9%
Expectoration	23.3%	24.7%	24.9%	23.1%	30.9%	31.7%	30.6%	42.3%
Bronchitis/bronchiolitis	8.9%	9.4%	10.5%	6.8% *	15.9%	16.7%	17.8%	15.4%
Rhinitis	76.4%	74.4%	77.7%	67.6% **	69.4%	76.3%	73.6%	74.1%
Pharyngitis	67.0%	61.0% **	62.6% *	55.1% **	46.5%	51.8%	48.8%	40.7%
Otitis/earache	9.3%	6.7% **	6.4% **	6.6% **	0.0%	3.1%	2.3%	3.7%
Gastrointestinal symptoms	15.8%	16.4%	17.1%	15.2%	17.1%	11.3%	10.1%	0.0% *
Conjunctivitis	11.5%	10.6%	11.8%	7.0% **	4.5%	6.9%	8.3%	3.7%
Adenopathy	9.0%	10.3%	11.5%	8.0%	6.9%	4.0%	2.1%	7.4%

^(a) These include all influenza cases, including those that were not subtyped/characterized.

^(b) sudden onset of symptoms is not presented as included in the ARI case definition; dyspnoea is not presented as only collected since the 2009–2010 season; myalgia and cephalalgia were not considered among children aged 0–4 years as they cannot report their subjective symptoms.

p-value for the comparison with influenza B patients of the same age group:

* <0.05

**<0.01