Table 1. Influenza positivity from 10 sentinel surveillance sites in India.
| City, State | 2009 | 2010 | 2011 | 2012 | 2013 | Total | |
|---|---|---|---|---|---|---|---|
| Srinagar, Jammu & Kashmir | Sample Tested | NA | NA | 771 | 1414 | 1735 | 3920 |
| Influenza Positives | 162 (21.2%) | 238 (16.8%) | 305 (17.6%) | 705 (18.0%) | |||
| Delhi, | Sample Tested | 1053 | 663 | 1006 | 1511 | 1338 | 5571 |
| Influenza Positives | 311 (29.5%) | 103 (15.5%) | 76 (7.6%) | 145 (9.6%) | 174 (13.0%) | 809 (14.5%) | |
| Dibrugarh, Assam | Sample Tested | 642 | 731 | 599 | 695 | 242 | 2909 |
| Influenza Positives | 111 (17.3%) | 89 (12.2%) | 74 (12.4%) | 156 (22.4%) | 34 (14.0%) | 464 (16.0%) | |
| Lucknow, Uttar Pradesh | Sample Tested | NA | NA | 951 | 1776 | 1257 | 3984 |
| Influenza Positives | 94 (9.9%) | 340 (19.1%) | 118 (9.4%) | 552 (13.9%) | |||
| Kolkata, West Bengal | Sample Tested | 455 | 896 | 1038 | 2211 | 962 | 5562 |
| Influenza Positives | 72 (15.8%) | 181 (20.2%) | 242 (23.3%) | 206 (9.3%) | 63 (6.5%) | 764 (13.7%) | |
| Nagpur, Maharashtra | Sample Tested | NA | NA | 590 | 917 | 1172 | 2679 |
| Influenza Positives | 29 (4.9%)* | 99 (10.8%) | 165 (14.1%) | 293 (10.9%) | |||
| Pune, Maharashtra | Sample Tested | 1746 | 1298 | 853 | 1029 | 962 | 5888 |
| Influenza Positives | 391 (22.4%) | 279 (21.5%) | 142 (16.6%) | 95 (9.2%) | 85 (8.8%) | 992 (16.8%) | |
| Chennai, Tamil Nadu | Sample Tested | 18821** | 7811** | 1523 | 1291 | 751 | 5959 |
| Influenza Positives | 1718 (9.1%) | 667 (8.5%) | 208 (13.7%) | 104 (8.1%) | 55 (7.3%) | 560 (9.4%) | |
| Vellore, Tamil Nadu | Sample Tested | 482 | 399 | 543 | 1021 | 587 | 3032 |
| Influenza Positives | 92 (19.1%) | 72 (18%) | 80 (14.7%) | 163 (16%) | 127 (21.6%) | 534 (17.6%) | |
| Alappuzha, Kerala | Sample Tested | 824 | 2457 | 1342 | 4623 | ||
| Influenza Positives | NA | NA | 154 (18.4%) | 215 (8.8%) | 137 (10.2%) | 506 (10.9%) | |
| All Centers Total | Sample Tested | 23199 | 11798 | 8698 | 14322 | 10348 | 44127 |
| Influenza Positives | 2695(11.6%) | 1391 (11.8%) | 1261 (14.5%) | 1761 (12.3%) | 1263 (12.2%) | 8371 (14%) |
* Influenza was detected by isolation in MDCK cells.
** A total of 24231 specimens were tested only for influenza A during 2009–2010 due to pandemic surge in testing capacity.