Table 3.

Relative risk of influenza type B detection among the elderly in comparison with younger age‐classes

Location [Ref]	Elderly vs children	Elderly vs adolescents	Elderly vs children/adolescents	Elderly vs adults
Hong Kong39	0.65	0.33	0.48	0.67
Vietnam40	NA	NA	0.94	1.18
Finland41	0.70	0.31	0.44	0.42
Australia27	0.91	0.66	0.73	1.04
Chile27	0.71	0.31	0.47	0.94
China (North)27	0.66	0.77	0.73	0.95
China (South)27	0.89	0.93	0.92	1.05
El Salvador27	0.89	1.51	1.16	1.79
England27	0.95	0.66	0.71	0.87
Guatemala27	0.91	0.88	0.90	2.27
Italy27	0.81	0.27	0.37	0.83
New Zealand27	0.57	0.36	0.43	0.70
Nicaragua27	0.42	0.39	0.40	2.92
Singapore27	0.96	0.64	0.66	0.96
Vietnam27	1.00	0.82	0.91	1.16
Canada (Manitoba)42	0.51	0.26	0.39	0.43
France43	1.29	0.90	1.03	1.35
Hong Kong44	0.58	0.45	0.52	1.05
Hong Kong45	0.80	0.48	0.61	1.01
China (Shanghai)46	0.91	0.77	0.81	0.98
Egypt47	1.29	1.05	1.14	1.28
China (Chongqing)48	0.74	0.48	0.55	1.17
Germany28	1.17	0.59	0.71	0.94
Spain (Madrid)29	1.11	0.49	0.83	1.25
Canada (Toronto)49	NA	NA	0.96	1.38
Australia30	0.93	0.59	0.68	0.95
United States51	0.86	NA	0.67a	0.91

^aThe age category is 5‐24 y; it therefore also includes young adults.