TABLE 1.
Number of specimens tested, proportion positive for influenza, and distribution of influenza types by year, region, and demographic characteristics, Lao PDR, 2016–2023.
| No. tested | No. (%) influenza positive | p value a | No. (%) positive for influenza type, among positive specimens | |||
|---|---|---|---|---|---|---|
| Influenza A | Influenza B | p value a | ||||
| Overall | 31,533 | 4096 (13.0) | 2760 (67.4) | 1336 (32.6) | ||
| Surveillance type | < 0.0001 | 0.0363 | ||||
| ILI | 18,492 | 2761 (14.9) | 1831 (66.3) | 930 (33.7) | ||
| SARI | 13,041 | 1335 (10.2) | 929 (69.6) | 406 (30.4) | ||
| Year | < 0.0001 | < 0.0001 | ||||
| 2016 | 4121 | 594 (14.4) | 259 (43.6) | 335 (56.4) | ||
| 2017 | 4505 | 692 (15.4) | 464 (67.1) | 228 (32.9) | ||
| 2018 | 3332 | 595 (17.9) | 469 (78.8) | 126 (21.2) | ||
| 2019 | 3204 | 476 (14.9) | 250 (52.5) | 226 (47.5) | ||
| 2020 | 3044 | 239 (7.9) | 210 (87.9) | 29 (12.1) | ||
| 2021 | 2570 | 107 (4.2) | 107 (100.0) | 0 (0.0) | ||
| 2022 | 4994 | 607 (12.2) | 315 (51.9) | 292 (48.1) | ||
| 2023 | 5763 | 786 (13.6) | 686 (87.3) | 100 (12.7) | ||
| Region | < 0.0001 | 0.5960 | ||||
| North | 15,979 | 1793 (11.2) | 1199 (66.9) | 230 (33.4) | ||
| Central | 3149 | 688 (21.8) | 458 (66.6) | 594 (33.1) | ||
| South | 12,405 | 1615 (13.0) | 1103 (68.3) | 512 (31.7) | ||
| Sex | 0.0048 | 0.2559 | ||||
| Male | 16,400 | 2042 (12.5) | 1393 (68.2) | 649 (31.8) | ||
| Female | 15,133 | 2054 (13.6) | 1367 (66.6) | 687 (33.4) | ||
| Age (years) | < 0.0001 | < 0.0001 | ||||
| 0–1 | 11,189 | 709 (6.3) | 493 (69.5) | 216 (30.5) | ||
| 2–4 | 5378 | 739 (13.7) | 533 (72.1) | 206 (27.9) | ||
| 5–14 | 4436 | 1092 (24.6) | 680 (62.3) | 412 (37.7) | ||
| 15–49 | 6929 | 1178 (17.0) | 771 (65.4) | 407 (34.6) | ||
| 50–64 | 2009 | 223 (11.1) | 172 (77.1) | 51 (22.9) | ||
| ≥ 65 | 1592 | 155 (9.7) | 111 (71.6) | 44 (28.4) | ||
| Influenza vaccination status | < 0.0001 | < 0.0001 | ||||
| Yes | 275 | 37 (13.5) | 29 (78.4) | 8 (21.6) | ||
| No | 11,428 | 1577 (13.8) | 972 (61.6) | 605 (38.4) | ||
| Do not know | 18,611 | 2262 (12.2) | 1601 (70.8) | 661 (29.2) | ||
| Missing data | 1219 | 220 (18.0) | 158 (71.8) | 62 (28.2) | ||
Abbreviations: ILI, influenza‐like illness; PDR, People's Democratic Republic; SARI, severe acute respiratory illness.
a
Calculated using chi‐square tests.