Background
Methods
Case definition
Sentinel site recruitment and case sampling
Specimen collection and storage
Sample process prior to RNA Extraction
RNA extraction
qRT-PCR screening
NoV GII genotyping
Phylogenic analysis
Statistical analysis
Results
NoV GII positive detection rate
Year | Adults | Children | ||||||
---|---|---|---|---|---|---|---|---|
No. of cases | Screen POS no. | Screen POS rate (%) | χ2 (P-value) | No. of cases | Screen POS no. | Screen POS rate (%) | χ2 (P-value) | |
2016 | 2443 | 339 | 13.88 | 18.02 (< 0.05) | 453 | 50 | 11.04 | 0.58 (= 0.75) |
2017 | 2123 | 352 | 16.58 | 499 | 60 | 12.02 | ||
2018 | 1908 | 228 | 11.95 | 457 | 48 | 10.50 | ||
Total | 6474 | 919 | 14.20 | 1409 | 158 | 11.21 |
Seasonal variation in NoV GII detection rate
NoV ORF1-ORF2 (polymerase-capsid region) genotypes overall constitution
Polymerase-capsid region genotype | No. of samples | Compositional percentage (%) |
---|---|---|
GII.Pe/GII.4 | 288 | 37.16 |
GII.P17/GII.17 | 198 | 25.55 |
GII.P16/GII.2 | 131 | 16.90 |
GII.P12/GII.3 | 53 | 6.84 |
GII.P7/GII.6 | 27 | 3.48 |
GII.P16/GII.13 | 23 | 2.97 |
GII.P21/GII.21 | 11 | 1.42 |
GII.Pe/GII.17 | 10 | 1.29 |
GII.P16/GII.4 | 8 | 1.03 |
GII.P8/GII.8 | 6 | 0.77 |
GII.P21/GII.13 | 6 | 0.77 |
GII.P15/GII.15 | 5 | 0.65 |
GII.P22/GII.5 | 4 | 0.52 |
GII.Pg/GII.1 | 3 | 0.39 |
GII.P7/GII.14 | 1 | 0.13 |
GII.P7/GII.9 | 1 | 0.13 |
Total | 775 | 100 |
Time distribution of main genotypes
Genotype | Number/Percentage (%) | ||||
---|---|---|---|---|---|
2016 | 2017 | 2018 | Total | χ2 (P-value) | |
GII.Pe/GII.4 | 137 (48.41%) | 107 (35.67%) | 44 (22.92%) | 288 (37.16%) | 32.31 (< 0.05) |
GII.P17/GII.17 | 82 (28.98%) | 76 (25.33%) | 40 (20.83%) | 198 (25.55%) | 4.00 (= 0.14) |
GII.P16/GII.2 | 5 (1.77%) | 81 (27.00%) | 45 (23.44%) | 131 (16.90%) | 73.77 (< 0.05) |
GII.P12/GII.3 | 14 (4.95%) | 16 (5.33%) | 23 (11.98%) | 53 (6.84%) | 10.62 (< 0.05) |
GII.P7/GII.6 | 7 (2.47%) | 4 (1.33%) | 16 (8.33%) | 27 (3.48%) | 18.41 (< 0.05) |
Others | 38 (13.43%) | 16 (5.33%) | 24 (12.5%) | 78 (10.06%) | 12.21 (< 0.05) |
Total | 283 (36.52%) | 300 (38.71%) | 192 (24.77%) | 775 (100.00%) |
Comparison of NoV GII genotypes found in adults and children outpatients
Population | Year | GII.Pe/GII.4 | GII.P17/GII.17 | GII.P16/GII.2 | GII.P12/GII.3 | GII.P7/GII.6 | Other genotypes | Total no. | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
No./(rate %) | χ2 (P-value) | No./(rate %) | χ2 (P-value) | No./(rate %) | χ2 (P-value) | No./(rate %) | χ2 (P-value) | No./(rate %) | χ2 (P-value) | No./(rate %) | χ2 (P-value) | |||
Adults | 2016 | 102 (41.98) | 19.16 (< 0.05) | 81 (33.33) | 3.54 (= 0.18) | 5 (2.06) | 66.78 (< 0.05) | 13 (5.35) | 9.94 (< 0.05) | 6 (2.47) | 16.38 (< 0.05) | 36 (14.81) | 11.18 (< 0.05) | 243 |
2017 | 78 (30.35) | 74 (28.79) | 75 (29.18) | 10 (3.89) | 4 (1.56) | 16 (6.23) | 257 | |||||||
2018 | 34 (21.52) | 39 (24.68) | 30 (18.98) | 18 (11.39) | 14 (8.86) | 23 (14.56) | 158 | |||||||
Children | 2016 | 35 (87.50) | 36.91 (< 0.05) | 1 (2.50) | 0.32 (= 1.00) | 0 (0.00) | 25.02 (< 0.05) | 1 (2.50) | 3.98 (= 0.14) | 1 (2.50) | 1.20 (= 0.53) | 2 (5.00) | 2.10 (= 0.39) | 40 |
2017 | 29 (67.44) | 2 (4.65) | 6 (13.95) | 6 (13.95) | 0 (0.00) | 0 (0.00) | 43 | |||||||
2018 | 10 (29.41) | 1 (2.94) | 15 (18.09) | 5 (14.71) | 2 (5.88) | 1 (2.94) | 34 | |||||||
Adults | Total | 214 (32.52) | 40.16 (< 0.05) | 194 (29.48) | 35.48 (< 0.05) | 110 (16.72) | 0.11 (= 0.79) | 41 (6.23) | 2.53 (= 0.16) | 24 (3.65) | 0.35 (= 0.61) | 75 (11.40) | 8.57 (< 0.05) | 658 |
Children | 74 (63.25) | 4 (3.42) | 21 (17.95) | 12 (10.26) | 3 (2.56) | 3 (2.56) | 117 |