1887
Research Open Access
Like 0

Abstract

Introduction

Findings from the community-based Canadian Sentinel Practitioner Surveillance Network (SPSN) suggest children were more affected by the 2018/19 influenza A(H1N1)pdm09 epidemic.

Aim

To compare the age distribution of A(H1N1)pdm09 cases in 2018/19 to prior seasonal influenza epidemics in Canada.

Methods

The age distribution of unvaccinated influenza A(H1N1)pdm09 cases and test-negative controls were compared across A(H1N1)pdm09-dominant epidemics in 2018/19, 2015/16 and 2013/14 and with the general population of SPSN provinces. Similar comparisons were undertaken for influenza A(H3N2)-dominant epidemics.

Results

In 2018/19, more influenza A(H1N1)pdm09 cases were under 10 years old than controls (29% vs 16%; p < 0.001). In particular, children aged 5–9 years comprised 14% of cases, greater than their contribution to controls (4%) or the general population (5%) and at least twice their contribution in 2015/16 (7%; p < 0.001) or 2013/14 (5%; p < 0.001). Conversely, children aged 10–19 years (11% of the population) were under-represented among A(H1N1)pdm09 cases versus controls in 2018/19 (7% vs 12%; p < 0.001), 2015/16 (7% vs 13%; p < 0.001) and 2013/14 (9% vs 12%; p = 0.12).

Conclusion

Children under 10 years old contributed more to outpatient A(H1N1)pdm09 medical visits in 2018/19 than prior seasonal epidemics in Canada. In 2018/19, all children under 10 years old were born after the 2009 A(H1N1)pdm09 pandemic and therefore lacked pandemic-induced immunity. In addition, more than half those born after 2009 now attend school (i.e. 5–9-year-olds), a socio-behavioural context that may enhance transmission and did not apply during prior A(H1N1)pdm09 epidemics.

Loading

Article metrics loading...

/content/10.2807/1560-7917.ES.2019.24.15.1900104
2019-04-11
2019-10-21
http://instance.metastore.ingenta.com/content/10.2807/1560-7917.ES.2019.24.15.1900104
Loading
Loading full text...

Full text loading...

/deliver/fulltext/eurosurveillance/24/15/eurosurv-24-15-4.html?itemId=/content/10.2807/1560-7917.ES.2019.24.15.1900104&mimeType=html&fmt=ahah

References

  1. Public Health Agency of Canada (PHAC). Weekly influenza reports. Ottawa: PHAC. [Accessed: 22 Mar 2019]. Available from: https://www.canada.ca/en/public-health/services/diseases/flu-influenza/influenza-surveillance/weekly-reports-2018-2019-season.html
  2. Centers for Disease Control and Prevention (CDC). FluView: Weekly U.S. influenza surveillance report. Atlanta: CDC. [Accessed: 22 Mar 2019]. Available from: https://www.cdc.gov/flu/weekly/
  3. European Centre for Disease Prevention and Control (ECDC). Flu News Europe: Joint ECDC-WHO/Europe weekly influenza update. Stockholm: ECDC. [Accessed: 22 Mar 2019]. Available from: http://flunewseurope.org
  4. Segaloff H, Melidou A, Adlhoch C, Pereyaslov D, Robesyn E, Penttinen P, et al. WHO European Region And The European Influenza Surveillance Network. Co-circulation of influenza A(H1N1)pdm09 and influenza A(H3N2) viruses, World Health Organization (WHO) European Region, October 2018 to February 2019. Euro Surveill. 2019;24(9):1900125.  https://doi.org/10.2807/1560-7917.ES.2019.24.9.1900125  PMID: 30862331 
  5. Skowronski DM, Chambers C, Sabaiduc S, De Serres G, Winter AL, Dickinson JA, et al. Integrated sentinel surveillance linking genetic, antigenic, and epidemiologic monitoring of influenza vaccine-virus relatedness and effectiveness during the 2013-2014 influenza season. J Infect Dis. 2015;212(5):726-39.  https://doi.org/10.1093/infdis/jiv177  PMID: 25784728 
  6. Skowronski DM, Chambers C, Sabaiduc S, De Serres G, Winter AL, Dickinson JA, et al. Beyond antigenic match: possible agent-host and immuno-epidemiological influences on influenza vaccine effectiveness during the 2015-2016 season in Canada. J Infect Dis. 2017;216(12):1487-500.  https://doi.org/10.1093/infdis/jix526  PMID: 29029166 
  7. Skowronski DM, Chambers C, Sabaiduc S, De Serres G, Winter AL, Dickinson JA, et al. A perfect storm: impact of genomic variation and serial vaccination on low influenza vaccine effectiveness during the 2014-2015 season. Clin Infect Dis. 2016;63(1):21-32.  https://doi.org/10.1093/cid/ciw176  PMID: 27025838 
  8. Skowronski DM, Chambers C, Sabaiduc S, Dickinson JA, Winter AL, De Serres G, et al. Interim estimates of 2016/17 vaccine effectiveness against influenza A(H3N2), Canada, January 2017. Euro Surveill. 2017;22(6):30460.  https://doi.org/10.2807/1560-7917.ES.2017.22.6.30460  PMID: 28205503 
  9. Skowronski DM, Chambers C, De Serres G, Dickinson JA, Winter A-L, Hickman R, et al. Early season co-circulation of influenza A(H3N2) and B(Yamagata): interim estimates of 2017/18 vaccine effectiveness, Canada, January 2018. Euro Surveill. 2018;23(5):18-00035.  https://doi.org/10.2807/1560-7917.ES.2018.23.5.18-00035  PMID: 29409570 
  10. Skowronski DM, Leir S, Sabaiduc S, Murti M, Dickinson JA, Olsha R, et al. Interim estimates of 2018/19 vaccine effectiveness against influenza A(H1N1)pdm09, Canada, January 2019. Euro Surveill. 2019;24(4):1900055.  https://doi.org/10.2807/1560-7917.ES.2019.24.4.1900055  PMID: 30696523 
  11. Doyle JD, Chung JR, Kim SS, Gaglani M, Raiyani C, Zimmerman RK, et al. Interim estimates of 2018-19 seasonal influenza vaccine effectiveness — United States, February 2019. MMWR Morb Mortal Wkly Rep. 2019;68(6):135-9.  https://doi.org/10.15585/mmwr.mm6806a2  PMID: 30763298 
  12. Kissling E, Rose A, Emborg H-D, Gherasim A, Pebody R, Pozo F, et al. European Ive Group. Interim 2018/19 influenza vaccine effectiveness: six European studies, October 2018 to January 2019. Euro Surveill. 2019;24(8):1900121.  https://doi.org/10.2807/1560-7917.ES.2019.24.1900121  PMID: 30808440 
  13. Chiu SS, Kwan MY, Feng S, Chan EL, Chua H, Wong JS, et al. Early season estimate of influenza vaccination effectiveness against influenza hospitalisation in children, Hong Kong, winter influenza season 2018/19. Euro Surveill. 2019;24(5):1900056.  https://doi.org/10.2807/1560-7917.ES.2019.24.5.1900056  PMID: 30722814 
  14. Statistics Canada. Table 17-10-0005-01: Population estimates on July 1st, by age and sex. Ottawa: Statistics Canada. [Accessed: 8 Feb 2019]. Available from: https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=1710000501
  15. Van Kerkhove MD, Hirve S, Koukounari A, Mounts AWH1N1pdm serology working group. Estimating age-specific cumulative incidence for the 2009 influenza pandemic: a meta-analysis of A(H1N1)pdm09 serological studies from 19 countries. Influenza Other Respir Viruses. 2013;7(5):872-86.  https://doi.org/10.1111/irv.12074  PMID: 23331969 
  16. Skowronski DM, Chambers C, Sabaiduc S, Janjua NZ, Li G, Petric M, et al. Pre- and postpandemic estimates of 2009 pandemic influenza A(H1N1) seroprotection to inform surveillance-based incidence, by age, during the 2013-2014 epidemic in Canada. J Infect Dis. 2015;211(1):109-14.  https://doi.org/10.1093/infdis/jiu366  PMID: 24973459 
  17. Somes MP, Turner RM, Dwyer LJ, Newall AT. Estimating the annual attack rate of seasonal influenza among unvaccinated individuals: A systematic review and meta-analysis. Vaccine. 2018;36(23):3199-207.  https://doi.org/10.1016/j.vaccine.2018.04.063  PMID: 29716771 
  18. Mossong J, Hens N, Jit M, Beutels P, Auranen K, Mikolajczyk R, et al. Social contacts and mixing patterns relevant to the spread of infectious diseases. PLoS Med. 2008;5(3):e74.  https://doi.org/10.1371/journal.pmed.0050074  PMID: 18366252 
  19. Béraud G, Kazmercziak S, Beutels P, Levy-Bruhl D, Lenne X, Mielcarek N, et al. The French connection: the first large population-based contact survey in France relevant for the spread of infectious diseases. PLoS One. 2015;10(7):e0133203.  https://doi.org/10.1371/journal.pone.0133203  PMID: 26176549 
  20. Wallinga J, Teunis P, Kretzschmar M. Using data on social contacts to estimate age-specific transmission parameters for respiratory-spread infectious agents. Am J Epidemiol. 2006;164(10):936-44.  https://doi.org/10.1093/aje/kwj317  PMID: 16968863 
  21. Linderman SL, Chambers BS, Zost SJ, Parkhouse K, Li Y, Herrmann C, et al. Potential antigenic explanation for atypical H1N1 infections among middle-aged adults during the 2013-2014 influenza season. Proc Natl Acad Sci USA. 2014;111(44):15798-803.  https://doi.org/10.1073/pnas.1409171111  PMID: 25331901 
  22. Morens DM, Burke DS, Halstead SB. The wages of original antigenic sin. Emerg Infect Dis. 2010;16(6):1023-4.  https://doi.org/10.3201/eid1606.100453  PMID: 20507764 
  23. Skowronski DM, Hottes TS, McElhaney JE, Janjua NZ, Sabaiduc S, Chan T, et al. Immuno-epidemiologic correlates of pandemic H1N1 surveillance observations: higher antibody and lower cell-mediated immune responses with advanced age. J Infect Dis. 2011;203(2):158-67.  https://doi.org/10.1093/infdis/jiq039  PMID: 21288814 
  24. Thompson WW, Shay DK, Weintraub E, Brammer L, Cox N, Anderson LJ, et al. Mortality associated with influenza and respiratory syncytial virus in the United States. JAMA. 2003;289(2):179-86.  https://doi.org/10.1001/jama.289.2.179  PMID: 12517228 
  25. Thompson MG, Shay DK, Zhou H, Bridges CB, Cheng PY, Burns E, et al. Centers for Disease Control and Prevention (CDC). Estimates of deaths associated with seasonal influenza --- United States, 1976-2007. MMWR Morb Mortal Wkly Rep. 2010;59(33):1057-62. PMID: 20798667 
  26. Ng S, Lopez R, Kuan G, Gresh L, Balmaseda A, Harris E, et al. The Timeline of Influenza Virus Shedding in Children and Adults in a Household Transmission Study of Influenza in Managua, Nicaragua. Pediatr Infect Dis J. 2016;35(5):583-6.  https://doi.org/10.1097/INF.0000000000001083  PMID: 26910589 
  27. Wang B, Russell ML, Fonseca K, Earn DJD, Horsman G, Van Caeseele P, et al. Predictors of influenza a molecular viral shedding in Hutterite communities. Influenza Other Respir Viruses. 2017;11(3):254-62.  https://doi.org/10.1111/irv.12448  PMID: 28207989 
  28. Belongia EA, Simpson MD, King JP, Sundaram ME, Kelley NS, Osterholm MT, et al. Variable influenza vaccine effectiveness by subtype: a systematic review and meta-analysis of test-negative design studies. Lancet Infect Dis. 2016;16(8):942-51.  https://doi.org/10.1016/S1473-3099(16)00129-8  PMID: 27061888 
  29. Statistics Canada. Table 13-10-0096-25 Influenza immunization in the past 12 months, by age group. Ottawa: Statistics Canada. [Accessed: 3 Mar 2019]. Available: https://www150.statcan.gc.ca/t1/tbl1/en/tv.action?pid=1310009625
  30. Grohskopf LA, Sokolow LZ, Broder KR, Olsen SJ, Karron RA, Jernigan DB, et al. Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices—United States, 2016-17 influenza season. MMWR Recomm Rep. 2016;65(5):1-54.
  31. Grohskopf LA, Sokolow LZ, Broder KR, Walter EB, Bresee JS, Fry AM, et al. Prevention and control of seasonal influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices—United States, 2017-18 influenza season. MMWR Recomm Rep. 2017;66(2):1-20.
  32. Public Health Agency of Canada (PHAC). Addendum – LAIV use in children and adolescents. Advisory Committee Statement (ACS). National Advisory Committee on Immunization (NACI). Canadian Immunization Guide Chapter on Influenza and Statement on Seasonal Influenza Vaccine for 2016-2017. Ottawa: PHAC. [Accessed: 24 Feb 2019]. Available from: https://www.canada.ca/content/dam/phac-aspc/migration/phac-aspc/naci-ccni/assets/pdf/addendum-2016-2017-laiv-ve-eng.pdf
  33. Monto AS, Sullivan KM. Acute respiratory illness in the community. Frequency of illness and the agents involved. Epidemiol Infect. 1993;110(1):145-60.  https://doi.org/10.1017/S0950268800050779  PMID: 8432318 
  34. Shang M, Blanton L, Brammer L, Olsen SJ, Fry AM. Influenza-associated pediatric deaths in the United States, 2010-2016. Pediatrics. 2018;141(4):e20172918.  https://doi.org/10.1542/peds.2017-2918  PMID: 29440502 
  35. Donaldson LJ, Rutter PD, Ellis BM, Greaves FE, Mytton OT, Pebody RG, et al. Mortality from pandemic A/H1N1 2009 influenza in England: public health surveillance study. BMJ. 2009;339:b5213.
  36. Kostova D, Reed C, Finelli L, Cheng P-Y, Gargiullo PM, Shay DK, et al. Influenza illness and hospitalizations averted by influenza vaccination in the United States, 2005-2011. PLoS One. 2013;8(6):e66312.  https://doi.org/10.1371/journal.pone.0066312  PMID: 23840439 
  37. Australian Government. 2018 Influenza Season in Australia: A summary from the National Influenza Surveillance Committee. Information Brief (updated on 16 November 2018). Canberra: Department of Health, Australian Government; 2018. Available from: http://www.health.gov.au/internet/main/publishing.nsf/Content/cda-surveil-ozflu-flucurr.htm/$File/2018-Season-Summary.pdf
  38. BC Centre for Disease Control. Influenza surveillance reports 2018-19 season. Vancouver: Provincial Health Services Authority. [Accessed: 22 Mar 2019]. Available from: http://www.bccdc.ca/health-professionals/data-reports/communicable-diseases/influenza-surveillance-reports
/content/10.2807/1560-7917.ES.2019.24.15.1900104
Loading

Data & Media loading...

Supplementary data

Comment has been disabled for this content
Submit comment
Close
Comment moderation successfully completed
This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error