Table 1.
Summary of the demographic and epidemiological information of included studies for meta-analysis.
| Study | Study type | N | Male (%) | Mean age (y) | Age range | Quality score | Exposure-Family cluster (%) | Sever/critical cases/ intensive care (%) | Underlying disease (%) | Other pathogensb (%) |
|---|---|---|---|---|---|---|---|---|---|---|
| Qiu et al. | Cross-sectional | 36 | 23 (64%) | 8.3 | 1y−16y | 19 | 32 (88.9%) | 0 | NA | NA |
| Wang et al. | Cross-sectional | 31 | 15 (48%) | 7.1 | 6m−17y | 18 | 28 (90.3%) | 0 | 1 (3.22%) | NA |
| Li W. et al. | Case series | 5 | 4 (80%) | 3 | 10m−6y | 13 | 4 (80%) | 0 | NA | NA |
| Lu et al. | Cross-sectional | 171 | 104 (60.8%) | 6.7 | 1d−15y | 17 | 154 (90%) | 3 (1.75%) | 10 (10.9%)a | 7 (7.69%)a |
| Li X. et al. | Cross-sectional | 30 | 18 (60%) | 6 | 0–14y | 13 | 16 (53.3%) | 1 (3.33%) | NA | 12 (40%) |
| Zheng et al. | Cross-sectional | 25 | 14 (56%) | 3 | 3m−14y | 13 | 16 (64%) | 2 (8%) | 2 (8%) | 6 (24%) |
| Feng et al. | Case series | 15 | 5 (33%) | 7 | 4y−14y | 12 | NA | 0 | NA | NA |
| Cai et al. | Case series | 10 | 4 (40%) | 6.2 | 3m−10.9y | 15 | 7 (70%) | 0 | NA | 0 |
| Liu H. et al. | Case series | 4 | 2 (50%) | 3.8 | 2m−9y | 13 | NA | 0 | NA | 1 (25%) |
| Zhang et al. | Cross-sectional | 10 | 3 (30%) | 4.9 | 11m−14y | 16 | 10 (100%) | 0 | NA | NA |
| Wei et al. | Case series | 9 | 2 (22%) | 0.5 | 1m26d−11m | 13 | 9 (100%) | 0 | 0 | NA |
| Yang et al. | Cross-sectional | 11 | 8 (73%) | 8.1 | 1y2m−15y7m | 14 | NA | 0 | NA | 0 |
| Liu M. et al. | Case series | 5 | 4 (80%) | 6 | 7m−13y | 11 | NA | 0 | NA | NA |
| Zhong et al. | Case series | 9 | 4 (44%) | 6.5 | 3m−12y | 13 | 9 (100%) | 0 | 0 | 0 |
The study of Lu et al. did not provide information of patients' underlying disease and other pathogenic infections, so we combined another two studies (with 91 and 115 subjects) which reported duplicated samples but complementary data.
Lu et al. tested respiratory syncytial virus, mycoplasma pneumonia, adenovirus, and influenza virus; Li X et al. tested mycoplasma pneumonia, Legionella pneumophila, EB virus and adenovirus; Zheng et al. tested mycoplasma pneumonia, influenza virus type B and enterobacter aerogenes; Cai et al. tested influenza virus type A and B; Liu H et al. tested mycoplasma pneumonia, influenza virus type A and B, chlamydia pneumonia, coxsackie virus B, human parainfluenza virus, respiratory syncytial virus, and adenovirus; Yang et al. tested mycoplasma pneumonia, influenza virus type A and B, chlamydia pneumonia, Legionella pneumophila, respiratory syncytial virus, and adenovirus; Zhong et al. tested influenza virus type A and B.
d, day; m, month; NA, not available; y, year.