Table 2.
Articles reporting the proportion of influenza B among all laboratory‐confirmed influenza
| Author | Design | Study years | Patient population | Number tested for influenza | Number (n) (proportion, %) of N with laboratory‐confirmed influenza | Number (n) (proportion, %) of type B among all laboratory‐confirmed influenza |
|---|---|---|---|---|---|---|
| Australia | ||||||
| Roche (2002)117 | Passive‐laboratory‐based surveillance | 1991‐2000 | Laboratory reports (nationwide network) | 340 730 | 16 805 (4.9, 4.6‐87.2 annually) | 3614 (21.5, 12.8‐95.4 annually) |
| Teichtahl (1997)118 | Case‐control study | Aug 1993‐July 1994 | Hospitalized adults with asthma exacerbation | 79 | 20 (25.2) | 2 (10.0) |
| Moore (2009)119 | Retrospective descriptive | May 1997‐Dec 2005 | Specimens from children <18 years (1 hospital) | 32 741 specimens | 1951 (6.0) | 304 (15.6) |
| Kelly (2000)120 | Prospective laboratory‐supported surveillance | 1998‐1999 | Patients with ILI (17‐26 general practitioners) | 152 | 65 (42.8) | 3 (4.6) |
| Caini (2015)34 | Prospective national surveillance of patients with ILI | 2001‐2012 | Laboratory‐confirmed influenza | 179 137 | 179 137(100) | 28 700 (16.0) |
| Druce (2005)23 | Prospective hospital‐based surveillance | May‐Sept 2002 & 2003 | Hospitalized patients with respiratory illness | 3095 | Only data by age | 55 (1.8) |
| Specimens collected from state‐wide influenza surveillance program | 1159 | ‐ | 133 (11.5) | |||
| Fielding (2007)25 | Prospective surveillance | May‐Oct 2006 | Patients with ILI (74 general practitioners) | 384 | 126 (32.8) | 15 (11.9) |
| Iskander (2009)24 | Prospective hospital‐based surveillance | June‐Oct 2006 | Hospitalized children <5 years with ILI (1 hospital) | 273 | 31 (11.4) | 9 (29.0) |
| Lambert (2008)26 | Prospective hospital‐based surveillance | July 2006‐Aug 2007 | Children with ARI presenting to hospital (1 hospital) | 303 specimens (295 patients) | 37 (12.2) | 7 (18.9) |
| Lester‐Smith (2009)28 | Retrospective descriptive | Jan‐Dec 2007 | Hospitalized children with influenza (1 hospital) | 122 | 122 (100) | 3 (2.5) |
| Miller (2008)27 | Prospective surveillance | Apr‐Sept 2007 | Patients with ILI (21 sentinel general practices) | 403 | 189 (46.9) | 24 (12.7) |
| Notified laboratory‐confirmed influenza | 1343 | 1343 (100) | 186 (13.8) | |||
| Grant (2011)121 | Prospective and retrospective surveillance | 2010 | Patients with ILI (32 general practices) | 478 | 170 (35.6) | 4 (2.4) |
| Notifications of laboratory‐confirmed influenza to Health Department | 1914 | 1914 (100) | 88 (4.6) | |||
| Macesic (2013)122 | Prospective hospital‐based surveillance | April‐Nov 2010 & 2011 | Community‐acquired influenza (8‐15 hospitals) | 572 | 572 (100) | 58 (10.1) |
| Nosocomial influenza | 26 | 26 (100) | 2 (7.7) | |||
| Levy (2014)29 | Prospective surveillance | 2010‐2012 | Patients with ILI (31‐57 general practices) | 448 (2010) 351 (2011) 1361 (2012) | 146 (32.6) 84 (29.9) (2011) 603 (44.3) (2012) | 56 (38.4) (2010) 18 (20.7) (2011) 259 (43) (2012) |
| Fielding (2013)30 | Prospective surveillance | 2012 | Patients with ILI (41 general practices) | 709 | 280 (39.5) | 38 (13.6) |
| Notified laboratory‐confirmed influenza | 5058 | 5058 (100) | 745 (14.7) | |||
| Influenza complications network | 389 | 389 (100) | 50 (12.8) | |||
| Sullivan (2014)123 | Prospective surveillance | 2012 | Patients with ILI (110 General practices nationally) | 1414 | 593 (41.9) | 106 (17.9) |
| Jennings (2015)124 | Prospective surveillance | 15 Jun‐12 Jul 2015 | Laboratory‐confirmed influenza (13 laboratories in New South Wales) | 1234 | 1234 (100) | 821 (66.5) |
| 1 Apr‐18 Jul | Laboratory‐confirmed influenza presenting to Emergency Departments (4 hospitals) | 88 | 88 (100) | 41 (46.6) | ||
| WHO55 | Prospective national surveillance | Jan‐Sept 2015 | Laboratory‐confirmed influenza | Not given | ‐ | (61%) |
| Laboratory‐confirmed influenza from general practices | 2565 | (30.9%) | (64%) | |||
| Hospitalized laboratory‐confirmed influenza | ‐ | ‐ | (52%) | |||
| Cambodia | ||||||
| Buecher (2010)31 | Prospective hospital‐based surveillance | Feb‐May 2005‐2007 | Patients with ILI during dry season (5 hospitals) | 234 | 4 (1.7) | 2 (50) |
| Mardy (2009)32 | Prospective hospital‐ and clinic‐based surveillance | 2006‐2008 | Patients with ILI (5 outpatient departments) and ALRTI (2 hospitals) (2007‐08) | 3148 (ILI) 1868 (ALRI) | 338 (10.7) (5.8‐15.3 annually) 64 (3.4) (1.4‐3.6 annually) | ILI & ALRTI 148 (43.8) (34‐57.7 annually) |
| Kasper (2012)125 | Prospective hospital‐based surveillance | Dec 2006‐Dec 2009 | Acutely ill patients with fever (9 hospitals in South‐central Cambodia) | 9968 | 1983 (19.9) | 631 (31.8) |
| Saha (2014)44 | Prospective clinic‐based surveillance | 2006‐2011 | Patients with ILI at sentinel centers | 10 105 | 1574 (15.6) (7.6‐18.8 annually) | (22.9‐65.6) (annually) |
| Horm (2014)33 | Prospective hospital‐based surveillance | 2009‐2011 | Patients with ILI (11 sites nationally) and ALRTI (2 hospitals) | 7376 (ILI) 2248 (ALRI) | 1262 (16.9) (14.5‐18.7 annually) 59 (2.6 (1.5‐3 annually) | ILI & ALRTI 515 (30.6) (12.6‐64.8 annually) |
| Timmermans (2016)97 | Prospective surveillance | May 2010‐Dec 2012 | Patients with ILI (4 sites in Western Cambodia) | 586 | 168 (29.7) | 76 (45.2) |
| China | ||||||
| Cheng (2013)35 | Prospective hospital‐ and clinic‐based surveillance (Shenzhen) | 1995‐2009 | Patients with URTI until 2003 (8 sites), ILI after 2003 (22‐31 sites) | 25 377 | 2678 (10.6) (0.2‐25 annually) | 757 (28.3) (2‐79 annually) |
| Tang (2008)126 | Prospective hospital‐based descriptive (Gangzhou) | Jan‐2001‐Dec 2006 | Hospitalized children <14 years with ALRI | 34 885 | 760 (2.2) | 72 (9.5) |
| Lin (2013)36 | Prospective hospital and laboratory‐based surveillance (Guangdong) | Jan 2004‐Dec 2012 | Patients with ILI (14 hospitals) | 107 115 | 17 454 (16.3) | 4978 (28.5) |
| ILI outbreak surveillance | 919 outbreaks | 828 outbreaks (90.1) | Multiple B outbreaks in 2005, 2007, 2010, 2012 | |||
| Caini (2015)34 | Prospective national ILI surveillance | 2006‐2012 | Laboratory‐confirmed influenza (South) | 122 215 | 122 215 (100) | 35 910 (29.4) |
| 2005‐2011 | (North) | 64 306 | 64 306 (100) | 19 956 (31.0) | ||
| Yang (2012)127 | Prospective outpatient surveillance (Beijing) | May 2006‐Jan 2010 | Patients ≥ 14 years with ARI (1 hospital) | 7776 | 1854 (23.8) | 405 (21.8) |
| Ji (2010)128 | Retrospective hospital‐based descriptive (Suzhou) | Jan 2007‐Dec 2008 | Hospitalized children <5 years respiratory infection (1 hospital) | 7789 | 120 (1.5) | 25 (20.8) |
| Yang (2009)37 | Prospective outpatient and ED surveillance (Beijing) | Sept 2007‐Apr 2008 | Patients with ILI (14 hospitals) | 2057 | 611 (29.7) | 450 (73.6) |
| Guo (2012)129 | Prospective outpatient surveillance (Zhuhai City) | 2008 | Patients with ILI (28 hospitals) | 1485 | 135 (9.1) | (23.7) |
| 2009 | 2144 | 604 (28.2) | (9.1) | |||
| Peng (2012)130 | Prospective hospital‐based surveillance (Wuhan) | Jul 2008‐Jun 2010 | Children ≤ 14 years with ILI (1 hospital) | 1472 | 455 (30.9) | 100 (22.0) |
| Ge (2012)38 | Prospective outpatient surveillance (Shanghai) | Jun 2009‐May 2011 | Children with ILI (1 hospital) | 2356 | 608 (25.8) | 142 (23.4) |
| Lu (2013)131 | Prospective descriptive (Jinan) | Aug 2009‐Sept 2010 | Patients ≥ 14 years with ARI (1 hospital) | 596 | 124 (20.8) | 75 (60.5) |
| Wei (2013)40 | Prospective hospital‐based surveillance | Apr 2009‐Mar 2011 | Patients with ILI | 6143 | 1645 (26.8) | 348 (21.2) |
| Zhu (2013)132 | Laboratory‐based descriptive (Hubei & Zhejiang) | 2009‐2010 | Patients with respiratory infection (inpatients and outpatients) | 341 | 54 (15.8) | 18 (33.3) |
| Zhao (2015)41 | Prospective outpatient surveillance (Shanghai) | 2009‐2014 | Patients with ILI | 71 354 | 19 974 (28.0) | 6688 (33.5) |
| Li (2013)133 | Prospective outpatient surveillance (Zhuhai City) | Jan‐Dec 2010 | Patients with ILI (1 hospital) | 924 | 187 (20.2) | 96 (51.3) |
| Yu (2013)39 | Prospective hospital‐based surveillance (Jingzhou City) | 2010‐2012 | Hospitalized patients with SARI (4 hospitals) | 16 208 | 2057 (12.7) | 998 (48.5) |
| Huo (2012)134 | Prospective outpatient surveillance (Nanjing) | Nov 2010‐ Oct 2011 | Patients with ILI (2 hospitals, 1 laboratory) | 486 | 178 (36.3) | 37 (20.8) |
| Chen (2014)135 | Prospective hospital‐based surveillance (Changsha) | 2010‐2012 | Patients with ILI (2 hospitals) | 2955 | 278 (9.4) | 83 (29.9) |
| Wang (2014)136 | Retrospective modeling study (Gangzhou) | Jan 2010‐Dec 2012 | Patients with ILI | 8258 | 1081 (13.1) | 360 (33.3) |
| Yu (2012)137 | Prospective hospital‐based descriptive (Beijing) | May 2010‐Apr 2011 | Patients ≥ 14 years in ED with ARI (1 hospital) | 416 | 70 (16.8) | 3 (4.3) |
| Fu (2015)138 | Prospective clinic‐based surveillance (Shanghai) | Jan 2011‐Dec 2013 | Patients with ILI (2 hospitals) | 1970 | 392 (19.9) | 162 (41.3) |
| Ju (2014)139 | Prospective hospital descriptive (Huizhou) | Jul 2011‐Jul 2013 | Hospitalized patients with ILI (1 hospital) | 1046 | 209 (20.0) | 74 (35.4) |
| Wang (2016)140 | Prospective hospital‐based surveillance (Suzhou)) | Apr 2011‐Mar 2014 | Children <5 years with ILI presenting to outpatient or ED | 3662 | 619 (16.9) | 349 (56.4) |
| Indonesia | ||||||
| Beckett (2004)42 | Laboratory‐based surveillance | Aug 1999‐Jan 2003 | Children >4 and adults with ILI at 6 sentinel centers | 1372 | 130 (9.5) | 33 (25.4) |
| Kosasih (2013)43 | Prospective health center and hospital‐based Surveillance | Jan 2003‐Dec 2007 | Inpatients and outpatients with ILI at 5 (2003) to 48 (2006‐07) sentinel centers | 21 030 | 4236 (20.1) | 1487 (35.1) |
| Caini (2015)34 | Prospective national surveillance of patients with ILI | 2003‐2007 | Laboratory‐confirmed influenza | 3653 | 3653 (100) | 1314 (36.0) |
| Saha (2014)44 | Prospective clinic‐based surveillance | 2010‐2011 | Patients with ILI at sentinel centers | 15 150 specimens | 2511 (16.6) | (49.9 in 2010, 24.8 in 2011) |
| Storms (2015)45 | Enhanced prospective surveillance in East Jakarta | Oct 2011‐Sept 2012 | Patients with ILI at 4 outpatient clinics | 3278 | 1131 (34.5) | 536 (47.4) |
| Patients with SARI at 6 hospitals | 1787 | 276 (15.4) | 132 (47.8) | |||
| Laos | ||||||
| Vongphrachanh (2010)47 | Prospective hospital‐based surveillance | Jan 2007‐Dec 2008 | Patients with ILI presenting to hospital OPD/ED (3 hospitals) | 526 | 155 (29.5) | 92 (59.3) |
| Aug‐Dec 2008 | Hospitalized ALRTI | 79 | 10 (12.7) | 4 (40.0) | ||
| Khamphaphongphane (2013)46 | Laboratory‐based surveillance | Jan 2008‐ Dec 2010 | Patients with ILI presenting to hospital OPD/ED (7 hospitals) | 2338 specimens | 523 (22.4) (20.9‐23 annually) | 142 (27.7) (2.7‐66.7 annually) |
| Saha (2014)44 | Prospective clinic‐based surveillance | 2006‐2011 | Patients with ILI at sentinel centers | 5949 | 1302 (21.9) (12.8‐29.8 annually) | (2.2‐56.5 annually) |
| Sentilhes (2013)48 | Prospective hospital‐based surveillance | Aug 2009‐Oct 2010 | Patients hospitalized with ALRTI | 292 specimens | 23 (7.9) | 5 (21.8) |
| Malaysia | ||||||
| Chan (1999)141 | Retrospective descriptive | Jan 1982‐Dec 1997 | Children <24 months with LTRI | 5697 | 77 (1.4) | 18 (23.4) |
| Khor (2012)81 | Retrospective hospital‐based descriptive | 1982‐2008 | Samples from hospitalized children ≤5 years (1 hospital) | 10 269 | 297 (2.9) | 64 (21.9) |
| Sam (2015)142 | Laboratory‐based surveillance | 1995‐2008 | Laboratory‐confirmed influenza 1 month to 49 years | 338 | 338 (100) | 88 (26.0) |
| Sam (2010)143 | Retrospective descriptive | 2002‐2007 | Hospitalized children <15 years with laboratory‐confirmed influenza | 132 | 132 (100) | 35 (26.5) |
| Saat (2010)49 | Prospective laboratory‐based surveillance | Jan 2005‐Dec 2009 | Patients with ILI (nationwide) | 7117 specimens | 993 (14.0) (10.2‐31.6 annually) | 305 (30.7) (18‐51 annually) |
| Saha (2014)44 | Prospective clinic‐based surveillance | 2006‐2011 | Patients with ILI at sentinel centers | 10 323 | 894 (8.7) (3.1‐13.4 annually) | (20.2‐62.6, 2006‐2010) |
| Myanmar | ||||||
| Hasegawa (2006)50 | Prospective hospital‐ and clinic‐based surveillance | Sept 2003‐Dec 2004 | Patients with ILI (1 hospital, 2 general practitioners) | 616 | 139 (22.6) | 6 (4.3) |
| Hasegawa (2006)51 | Prospective hospital‐ and clinic‐based surveillance | 2005 | Patients with ILI (1 hospital, 2 general practitioners) | 992 | 268 (27.0) | 125 (46.6) |
| Dapat (2009)52 | Prospective hospital‐ and clinic‐based surveillance | 2005‐2007 | Patients with ILI (1 hospital, 1 clinic) | 2618 | 522 (19.9) (24 in 2005, 11.4 in 2006, 19 in 2007) | 267 (51.1) (42 in 2005, 0 in 2006, 67 in 2007) |
| New Zealand | ||||||
| Huang (2008)53 | Prospective national surveillance | 1997‐2006 | All influenza diagnoses sentinel general practice, laboratory, hospital, and mortality surveillance | ‐ | Average 718 annually | (0‐92 annually) |
| Laing (2001)144 | Prospective hospital‐based surveillance | Jul 1999‐Jul 2000 | Hospitalized adults >18 with CAP | 474 | 39 (8.2) | 8 (20.5) |
| Caini (2015)34 | Prospective national surveillance of patients with ILI | 2000‐2012 | Laboratory‐confirmed influenza | 17 629 | 17 629 (100) | 2965 (16.8) |
| Jennings (2004)145 | Prospective hospital‐based descriptive | Jul‐Nov 2001 | Children with ARI (1 hospital) | 75 | 10 (13.3) | 7 (70.0) |
| Huang (2007)54 | Prospective national surveillance | 2005 | Laboratory‐confirmed influenza sentinel general practice, laboratory and hospital‐based surveillance | 845 | 845 (100) | 734 (86.9) |
| Turner (2014)146 | Prospective hospital‐ and clinic‐based surveillance | Apr‐Sept 2013 | Patients with ILI (18 sentinel general practices) and SARI (4 hospitals) | 1298 (ILI) 886 (SARI) | 182 (21) 391 (30) | ILI&SARI 221 (39) |
| WHO55 | Sentinel ILI & SARI and laboratory surveillance | Jan‐Sept 2015 | Laboratory‐confirmed influenza | Not given | 5235 (100) | 680 (13%) |
| Patients with ILI SARI patients | 13891206 | 614 (44.2%)285 (23.6) | 308 (50%)Not mentioned | |||
| Philippines | ||||||
| Saha (2014)44 | Prospective clinic‐based surveillance | 2006‐2011 | Patients with ILI at sentinel centers | 69 108 | 12 607 (18.2) (6.9‐33.1 annually) | (Range 2.3‐75.7) |
| Suzuki (2012)147 | Prospective descriptive | May 2008‐May 2009 | Hospitalized children 8 day‐13 years with severe CAP (1 center) | 819 | 29 (3.5) | 11 (37.9) |
| Tallo (2014)60 | Prospective clinic‐based surveillance | Jan 2009‐Dec 2011 | Patients with ILI and SARI at sentinel centers | 5915 (ILI) 2659 (SARI) | 1282 (21.7) (12.3‐25.6 annually) 226 (8.5) (6‐11.2 annually) | 397 (31.0) (6‐61.2 annually) 72 (31.9) (11.4‐49.4 annually) |
| Otomaru (2015)61 | Prospective clinic‐based surveillance | Jan 2010‐Mar 2013 | Patients with ILI at sentinel centers | 2031 | 225 (11.1) (3.2‐16.0 annually) | 104 (46.2) (23.8‐81.3 annually) |
| PNG | ||||||
| Kono (2014)56 | Prospective surveillance | 2010 | Patients with ILI (2 hospitals) | 300 | 88 (29.3) | 38 (43.2) |
| Singapore | ||||||
| Chew (1998)82 | Retrospective descriptive | Sept 1990‐Sept 1994 | Patients tested for respiratory pathogens (2 hospitals) | 12 354 specimens | 426 (3.4) | 92 (21.6) |
| Chow (2006)62 | Retrospective surveillance | Jan 1996‐ Dec 2003 | Samples from outpatients or inpatients with ILI (National Influenza Centre) | 57 060 specimens | 3829 (6.7) | 333 (13.9) |
| Yang (2011)63 | Retrospective surveillance | 2004‐2006 | Samples from outpatients or inpatients with ILI (Ministry of Health) | 29 329 specimens | 1291 (5.5) | 305 (23.6) (16.3‐33.0 annually) |
| Seah (2010)68 | Prospective descriptive | Mar 2006‐Apr 2007 | Military personnel with febrile respiratory illness (1 camp) | 1354 specimens | 489 (36.1) | 159 (32.5) |
| Virk (2014)65 | Prospective surveillance | May‐Oct 2007 | Students and staff with ILI (National University of Singapore) | 266 | 56 (21.1) | 9 (16.1) |
| Tan (2015)64 | Prospective surveillance | 2007‐2009 | Students and staff with ILI (National University of Singapore) | 500 | 164 (32.8) | 11 (6.7) |
| Saha (2014)44 | Prospective clinic‐based surveillance | 2007‐2011 | Patients with ILI at sentinel centers | 55 449 | 12 801 (23.1) | (2.7‐79.1 2007‐2011) |
| Caini (2015)34 | Prospective national surveillance of patients with ILI | 2007‐2012 | Laboratory‐confirmed influenza | 12 001 | 12 001 (100) | 2311 (19.3) |
| Yap (2012)67 | Prospective descriptive | May 2009‐June 2010 | Military personnel with febrile respiratory illness (4 camps) | 2858 | 821 (28.7) | 269 (32.8) |
| Tan (2014)66 | Prospective surveillance | May 2009‐Oct 2012 | Military personnel with febrile respiratory illness (5 camps) | 7733 | 972 (12.6) | 449 (46.2) |
| South Korea | ||||||
| Yun (1995)78 | Prospective hospital‐based descriptive | Nov 1990‐Apr 1994 | Children with ALRI + children visiting the OPD or with nosocomial ALRI | 804 specimens (712 patients) | 42 (5.2) | 11 (26.2) |
| Lee (2007)148 | Prospective clinical & laboratory‐based surveillance | Sept 2000‐Oct 2001 | Patients with ILI | 2972 | 144 (4.8) | 0 (0) |
| Kim (2008)77 | Retrospective descriptive | Mar 2004‐Dec 2005 | Hospitalized children <15 years with LRTI with NPA | 400 | 76 (19) | 32 (42.1) |
| Seo (2014)69 | Retrospective laboratory‐based descriptive | Jan 2005‐Dec 2008 | Children <19 years with ARI | 21 641 specimens | 1116 (5.2) | 484 (43.4) |
| Adults with ARI | 2165 specimens | 217 (10.0) | 121 (55.8) | |||
| Choi (2012)149 | Prospective descriptive | Mar 2010‐Feb 2011 | Adults ≥ 18 year in ICU with severe CAP or HCAP | 198 | 12 (6.1) | 1 (8.3) |
| Noh (2013)150 | Prospective hospital‐based surveillance | Sept 2011‐Jun 2012 | Adults ≥ 18 years who visited an ED with ILI | 1983 | 846 (42.7) | 169 (20.0) |
| Song (2013)76 | Prospective ED‐based surveillance | Oct 2011‐Sept 2012 | Laboratory‐confirmed influenza | 7213 | 7213 (100) | 3217 (44.6) |
| Wie (2013)151 | Prospective ED‐based surveillance | Oct 2011‐May 2012 | Adults with ILI | 2129 | 850 (39.9) | 194 (22.8) |
| Seo (2014)152 | Prospective ED‐based surveillance | Oct‐2011‐June 2012 | Patients with ILI at ED | 4490 tested | Not given | Max 58% of weekly samples |
| Choi (2015)153 | Retrospective case control | Sept 2011‐May 2012 | Patients visiting hospital with ILI | 7390 tested | 1130 (15.3) | 452 (40) |
| Ahn (2015)154 | Retrospective laboratory‐based descriptive | Jan 2012‐Apr 2013 | Adults >16 tested for respiratory viruses | 291 specimens (282 patients) | 47 (16.1) | 4 (8.5) |
| Taiwan | ||||||
| Lin (2004)80 | Prospective hospital‐based descriptive | Aug 1995‐July 1997 | Pediatric outpatients with URTI | 910 | 112 (12.3) | 58 (51.8) |
| Tsai (2001)79 | Prospective hospital and clinic‐based Surveillance | Jan 1997‐Dec 1999 | Children <12 years with RTI (inpatients and outpatients) | 6986 | 565 (8.1) | 181 (32.0) |
| Huang (2009)155 | Retrospective descriptive | Jan 1997‐May 2007 | Laboratory‐confirmed influenza | 2651 | 2651 (100) | 1168 (44.1) |
| Hu (2004)156 | Retrospective descriptive | Jan 2000‐Dec 2001 | Children with laboratory‐confirmed influenza | 197 | 197 (100) | 124 (62.9) |
| Shih (2005)157 | Prospective laboratory surveillance | Oct 2000‐Mar 2004 | Patients with suspected RTI (inpatients and outpatients) | 32 775 | 3244 (9.9) | 1,2.75 (39.3) |
| Chi (2008)158 | Retrospective hospital‐based descriptive | Jan 2001‐Dec 2006 | Children with LRTI (inpatients and outpatients) | 20 405 specimens | 745 (3.7) | 118 (15.8) |
| Jian (2008)159 | Prospective laboratory surveillance | 2003‐2006 | Patients with suspected RTI (inpatients and outpatients) | 34 312 | 4007 (11.7) | 1336 (33.3) |
| Lin (2013)160 | Prospective laboratory and sentinel physician‐based surveillance | 2003‐2007 | Patients with URTI or LRTI symptoms | 12 190 | 1150 (9.4) | 651 (56.6) |
| Jian (2008)161 | Prospective laboratory surveillance | 2004‐2005 | Laboratory‐confirmed influenza | 1183 | 1183 (100) | 971 (82.1) |
| 2006‐2007 | 1534 | 1534 (100) | 1219 (79.5) | |||
| Wang (2009)162 | Retrospective and prospective descriptive | Nov 2006‐Feb 2007 | Children <18 years with ILI (inpatients, ED, outpatients) | 198 specimens (196 children) | 101 (51.0) | 87 (86.1) |
| Chen (2012)70 | Prospective hospital‐based descriptive | Jan 2009‐March 2011 | Children <24 months hospitalized with bronchiolitis | 113 | 5 (4.4) | 0 (0) |
| Chuang (2012)112 | Prospective national surveillance | 2009‐2010 | Samples from patients with ARTI | 14 788 specimens | 3970 (26.9) | 545 (13.7) |
| 2010‐2011 | Samples from patients with ARTI | 11 813 specimens | 2767 (23.4) | 489 (17.7) | ||
| 2009‐2010 | Patients with influenza hospitalized with | 1297 | 1297 (100) | 82 (6.3) | ||
| 2010‐2011 | Pulmonary complications | 1751 | 1751 (100) | 50 (2.9) | ||
| Lo (2013)71 | Prospective national surveillance | Jun 2011‐Jun 2012 | Outpatients with ILI | 14 943 | 3285 (22.0) | 2382 (72.5) |
| Suspected influenza with complications | 2675 | 1704 (63.7) | 1034 (60.7) | |||
| Thailand | ||||||
| Suzuki (1997)163 | Prospective surveillance | Each August 1991‐1994 | Patients with suspected influenza (2 hospitals) | 186 specimens | 32 (17.2) | 11 (34.4) |
| Sirivichayakul (2000)164 | Prospective descriptive | June 1998‐May 1999 | Nursing students with ILI (University) | 106 | 35 (33.0) | 2 (5.7) |
| Thawatsupha (2000)165 | Prospective hospital‐based surveillance | Jan‐Dec 2001 | Outpatients with ARI (6 hospitals) | 711 specimens | 338 (54.6) | 102 (30.2) |
| Olsen (2010)84 | Prospective hospital‐based surveillance | Sept 2003‐Dec 2005 | Hospitalized patients with acute LRTI (all hospitals in 2 provinces) | 3910 | 586 (15.0) | 150 (25.6) |
| Suntarattiwong (2007)166 | Prospective descriptive hospital‐based study | July 2004‐July 2005 | Hospitalized children 0‐5 years with LRTI (1 hospital) | 456 | 39 (8.6) | 5 (12.8) |
| Chittaganpitch (2011)72 | Prospective surveillance | 2004‐2010 | Patients with ILI at 11 sentinel centers, | 19 121 | 3896 (20.4) (15‐25 annuallya) | 1284 (33.0 range 13‐43a) |
| Sep‐Dec 2010 | Inpatients with SARI at 3 hospitals | 336 | 71 (21.1) | 20 (28.2) | ||
| Simmerman (2009)74 | Prospective hospital‐based surveillance | Jan 2005‐Dec 2008 | Hospitalized patients with pneumonia (all hospitals in 2 provinces) | 13 119 | 1391 (10.6) (4.1‐16.0 annually) | 444 (31.9) (range 13.6‐44.9 per year) |
| Hara (2011)167 | Hospital‐based descriptive | 2006‐2008 | Hospitalized patients with CAP (hospital and HIV center) | 119 | 7 (5.9) | 1 (14.3) |
| Saha (2014)44 | Prospective clinic‐based surveillance | 2007‐2011 | Patients with ILI at sentinel centers | 17 421 | 3802 (21.8) (18.4‐25.5 annually) | (12.9‐42.9) |
| Baggett (2012)83 | Prospective active, population‐based Surveillance | Jan 2009‐Dec 2010 | Hospitalized patients with acute LRTI (all hospitals in 2 provinces) | 7207 | 902 (12.5) | 120 (13.3) |
| Prachayangprecha (2013)168 | Prospective hospital‐based surveillance | Jun 2009‐Jul 2012 | Patients with ILI attending hospitals in Bangkok | 6050 | 2969 (49.0) | 3% of tested samples |
| Dawood (2014)114 | Prospective hospital‐based surveillance | July‐Dec 2010, 2011 | Hospitalized patients with ARI (all hospitals in 2 provinces) | 1545 | 279 (18.1) | 32 (11.5) |
| Tewawong (2015)73 | Laboratory‐based surveillance | Jan 2010‐Feb 2014 | Samples from patients with ILI (3 provinces) | 14 418 specimens | 3050 (21.2) | 471 (15.4) |
| Vietnam | Prospective laboratory‐based surveillance | |||||
| Nguyen (2007)57 | 2001‐2003 | Outpatients with ILI (12 centers) | 4708 | 119 (2.5) | 59 (49.6) (range 0‐77) | |
| Do (2011)169 | Prospective hospital‐based descriptive | Nov 2004‐Jan 2008 | Hospitalized children <15 years with ARI (1 center) | 309 | 51 (16.5) | 24 (47.1) |
| Nguyen (2009)58 | Prospective hospital and clinic‐based surveillance | Jan 2006‐Dec 2007 | Outpatients with ILI (15 clinics) | 11 082 | 2112 (19.1) | 585 (27.7) |
| Nguyen (2013)59 | Prospective surveillance | Jan 2006‐ Dec 2010 | Outpatients with ILI (7‐15 centers) | 29 804 | 6616 (21.9) (18‐26 annually) | 2163 (33.2) (23.3‐51.6 annually) |
| Saha (2014)44 | Prospective clinic‐based surveillance | 2006‐2011 | Patients with ILI at sentinel centers | 29 499 | 5241 (17.8) | (Range 0‐41.3.8) |
| Caini (2015)34 | Prospective national surveillance of patients with ILI | 2006‐2013 | Laboratory‐confirmed influenza | 8647 | 8647 (100) | 3011 (34.8) |
| Takahasi (2013)75 | Prospective descriptive | Sept 2009‐Aug 2010 | Hospitalized patients ≥ 15 years with LRTI (1 center) | 323 | 45 (13.9) | 13 (28.9) |
| WHO Western Pacific region | ||||||
| 14 countries170 | Regional ILI and laboratory surveillance | 2006 | Data from national influenza centers (patients with ILI) | 65 103 | 7425 (11.4) | 3032 (40.8) |
| 2007 | 92 939 | 11 143 (12.0) | 3846 (34.5) | |||
| 2008 | 94 274 | 11 025 (11.7) | 3599 (32.6) | |||
| 2009 | 366 164 | 115 554 (31.6) | 4886 (4.2) | |||
| 2010 | 307 584 | 51 573 (16.8) | 25 565 (49.6) | |||
A(L)RTI, acute (lower) respiratory tract infection; CAP, community‐acquired pneumonia; ED, emergency department; GP, general practice; HCAP, healthcare‐associated pneumonia; HIV, human immunodeficiency virus; ICU, intensive care unit; ILI, influenza‐like illness; LRTI, lower respiratory tract infections; NPA, nasopharyngeal aspirate; OPD, outpatient department; PNG, Papua New Guinea; P&I, pneumonia and influenza; RTI, respiratory tract infection; SARI, severe acute respiratory illness.
a
Percentage from 2004 data not taken as only 11 subjects included in the 2004 surveillance.