Table 3.

Frequency of Influenza co-infection among patients with COVID-19 based on different subgroups.

patients with COVID-19 and Influenza		Prevalence% (95% CI)	Number of studies	Number of patients	I-squared
Overall		0.8 (0.4–1.3)	11	79	76.6%
Continent	America	0.4 (0.0–0.7)	4	6	43.4%
	Asia	4.5 (0.1–7.9)	5	70	84.4%
Country	China	3.1 (0.2–6)	4	47	81.7%
	USA	0.7 (0.0–1.4)	3	5	52.6%
Gender	Male	5.3 (1.3–9.4)	4	30	80.1%
	Female	9.1 (0.6–17.2)	3	31	83.5%
Virus type	Influenza virus A	8 (5.6–10.4)	9	67	62.6%
	Influenza virus B	5.5 (2.8–8.3)	4	9	52.9%
Age	<50 years	1.7 (0.4–3)	3	9	51.2%
	More than 50 years	4.6 (1.4–10.6)	3	38	87.6%