Table 1. Season indicators reported up to week 52 compared to recent pre-pandemic seasons, 2017–2018 to 2019–2020.

Indicator		2022–2023	2019–2020	2018–2019	2017–2018
Epidemic onset		Week 43	Week 47	Week 43	Week 45
Onset to peak		5 weeks	14 weeks	8 weeks	14 weeks
1st report of localized activity		Week 35	Week 40	Week 38	Week 36
Peak percent positivity week (%)		Week 47 (23.8%)	Week 6 (29.7%)	Week 52 (28.9%)	Week 7 (32.5%)
Dominant circulating influenza type (%)		Influenza A (99%)	Influenza B (51%)	Influenza A (99%)	Influenza A (74%)
Dominant circulating influenza A subtype (%)		H3N2 (94%)	H3N2 (68%)	H1N1 (93%)	H3N2 (96%)
Proportion of detections among ages 65 years and older (%)		26	21	16	44
Proportion of detections among ages 19 years and younger (%)		42	44	41	19
Provincial and territorial severe outcomesa	Cumulative hospitalization rate (per 100,000)	41	7	13	19
	Hospitalizations	3,411	618	1,064	1,493
	ICU admissions	301	73	151	114
	Deaths	182	22	27	34
Paediatric severe outcomesb	Hospitalizations	1,505	264	414	195
	ICU admissions	183	57	71	35
	Deaths	6	0	fewer than 5	fewer than 5
Outbreaks	Total outbreaks	534	146	86	288
	Proportion of outbreaks in LTCFs (%)	54	58	43	57

Abbreviations: ICU, intensive care unit; LTCFs, long-term care facilities

^a Influenza-associated hospitalizations are reported by Alberta, Manitoba, New Brunswick, Newfoundland and Labrador, Northwest Territories, Nova Scotia, Prince Edward Island and Yukon. Only hospitalizations that require intensive medical care are reported by Saskatchewan

^b Paediatric influenza-associated severe outcomes are reported by the Immunization Monitoring Program Active (IMPACT) network. The IMPACT paediatric sentinel hospital network consists of 12 paediatric hospitals across Canada, located in Alberta, British Columbia, Quebec, Ontario, Nova Scotia, Newfoundland and Labrador, Saskatchewan and Manitoba