Table 1 Characteristic changes of HFMD cases in 2013–2015, 2017–2019 and 2020–2022 of chengdu area

Gender, n(%)

0.019^a

0.334^a

 Male

7317 (58.08)

4636 (56.43)

1922 (57.41)

 Female

5282 (41.92)

3580 (43.57)

1426 (42.59)

 Male Female

1.39

1.29

1.34

Median age, month (P25, P75)

26 (16–36)

25 (15–36)

25 (16–36)

0.331^b

 < 0.001^b

Age group,month, n (%)

 < 0.001^a

 < 0.001^a

 0–11

1335 (10.60)

1069 (13.01)

372 (11.11)

 12–23

4329 (34.36)

2868 (34.91)

1170 (34.95)

 24–47

5658 (44.91)

3105 (37.79)

1201 (35.87)

 > 48

1277 (10.14)

1174 (14.29)

605 (18.07)

Serotypes, n (%)

 < 0.001^a

 < 0.001^a

 EV-A71

1713 (13.60)

150 (1.83)

0 (0)

 CV.A16

1759 (13.96)

891 (10.84)

152 (4.54)

 Other enterovirus 1

9127 (72.44)

7175 (87.33)

3196 (95.45)

 CV-A6

–

–

1687 (50.39)

 CV-A10

–

–

362 (10.81)

 Other enterovirus 2

–

–

1147 (34.26)

In/outpatient, n (%)

 < 0.001^a

0.020^a

 Inpatient

1061 (8.42)

390 (6.73)

126 (3.76)

 Outpatient

11,538 (91.58)

7826 (93.27)

3222 (96.24)