Table 1.

Background characteristics of the selected studies

	Authors	Study location	Study design	Number of newborn	Number of positive newborns
1	Villar et al. [7]	Multinational study	Case report	706	54
2	Chen et al. [45]	China	Retrospective cohort	9	0
3	Dong et al. [14]	China	Case report	1	0
4	Ferrazzi et al. [18]	Italy	Retrospective cohort	3	42
5	Liu et al. [33]	China	Case report	3	0
6	Lu et al. [93]	China	Case report	1	0
7	Di et al. [94]	China	Retrospective cohort	9	0
8	Jinhua et al. [95]	China	Retrospective cohort	17	0
9	Chao et al. [96]	China	Case report	1	0
10	Siyin et al. [97]	China	Case report	1	0
11	Huiting et al. [11]	China	Retrospective cohort	4	1
12	Kirtsman et al. [31]	Canada	Case report	3	3
13	Lopian et al. [39]	Israel	Retrospective cohort	21	1
14	Fenizia et al. [35]	Italy	Prospective study	56	0
15	González et al. [62]	Spain	Retrospective cohort	14	440