1. Bresee J, Fry A, Sambhara S, Cos N. Inactivated influenza vaccines. In: Plotkin S, Orenstein W, Offit P, editors. Vaccines. 7th ed. Philadelphia: Elsevier; 2018. p. 456-88.
2. Centers for Disease Control and Prevention. Influenza (Flu): Influenza signs and symptoms and the role of laboratory diagnostics [Internet]. Atlanta: Centers for Disease Control and Prevention; 2016 [updated 2020 August 31; cited 2020 November 11]. Available from: https://www.cdc.gov/flu/professionals/diagnosis/labrolesprocedures.htm
3. Ministry of Health. Communicable disease control manual 2012 [Internet]. Wellington: Ministry of Health; 2012 [updated 2021 February; cited 2021 March 1]. Available from: https://www.health.govt.nz/publication/communicable-disease-control-manual
4. Somes MP, Turner RM, Dwyer LJ, Newall AT. Estimating the annual attack rate of seasonal 5. influenza among unvaccinated individuals: A systematic review and meta-analysis. Vaccine. 2018;36(23):3199-207.
5. Yan J, Grantham M, Pantelic J, Bueno de Mesquita PJ, Albert B, Liu F, et al. Infectious virus in exhaled breath of symptomatic seasonal influenza cases from a college community. Proc Natl Acad Sci U S A. 2018;115(5):1081-6.
6. Carrat F, Vergu E, Ferguson NM, Lemaitre M, Cauchemez S, Leach S, et al. Time lines of infection and disease in human influenza: A review of volunteer challenge studies. Am J Epidemiol. 2008;167(7):775-85.
7. Huang Y, Zaas AK, Rao A, Dobigeon N, Woolf PJ, Veldman T, et al. Temporal dynamics of host molecular responses differentiate symptomatic and asymptomatic influenza A infection. PLoS Genet. 2011;7(8):e1002234.
8. Huang Q. Key findings - SHIVERS. New Zealand Influenza Symposium; 2016 November 2; Wellington, New Zealand. Auckland: The Immunisation Advisory Centre; 2017.
9. Institute of Environmental Science and Research Ltd (ESR). Flu surveillance and research [Internet]. Wellington: Institute of Environmental Science and Research Ltd (ESR); 2019 [updated October 2019; cited 2020 January 29]. Available from: https:// www.esr.cri.nz/our-services/consultancy/flu-surveillance-and-research/
10. Institute of Environmental Science and Research Ltd (ESR). Flu surveillance and research [Internet]. Wellington: Institute of Environmental Science and Research Ltd (ESR); 2020 [updated 2020 November; cited 2020 December 11]. https:// www.esr.cri.nz/our-services/consultancy/flu-surveillance-and-research/
11. Tang JW, Bialasiewicz S, Dwyer DE, Dilcher, M, Tellier R, Taylor J, et al. Where have all the viruses gone? Disappearance of seasonal respiratory viruses during the COVID-19. Journal of Medical Virology. 2021; 93(7):4099-4101
12. Huang S, Wood T, Jelley L, Jennings T, Jefferies S, Daniells K, et al. Impact of the COVID-19 nonpharmaceutical interventions on influenza and other respiratory viral infections in New Zealand. Nature Communications [Internet]. 2021; 12(1001)
13. Public Health England. Weekly national Influenza and COVID19 Surveillance report: Week 49 report (up to week 48 data) https://assets.publishing.service.gov.uk/government/uploads/system/ uploads/attachment_data/file/940878/Weekly_ Flu_and_COVID-19_report_w49.pdf
14. Olsen SJ, Winn AK, Budd AP, Prill MM, Steel J, Midgely CM, et al. Changes in Influenza and Other Respiratory Virus Activity During the COVID-19 Pandemic – United States, 2020-2021. Centers for Disease Control and Prevention – Morbidity and Mortality Weekly Report July 23, 2021; 70(29):1014- 1019
15. European Centre for Disease Prevention and Control. COVID-19 situation update for the EU/EEA and the UK, as of 9 December 2020.https://www.ecdc.europa.eu/en/cases-2019-ncov-eueea.
16. Lee K, Jalal H, Raviotta JM, Krauland MG, Zimmerman RK, Burke DS, et al. Estimating the Impact of Low Influenza Activity in 2020 on Population Immunity and Future Influenza Seasons in the United States. Open Forum Infectious Diseases. 2022;9(1).
17. Stowe J, Tessier E, Zhao H, Guy R, Muller-Pebody B, Zambon M, et al. Interactions between SARS-CoV-2 and influenza, and the impact of coinfection on disease severity: a test-negative design. International Journal of Epidemiology. 2021; 50(4):1124-1133.
18. Dadashi M, Khaleghnejad S, Elkhichi P, Goudarzi M, Goudarzi H, Taghavi A, et al. COVID-19 and Influenza Co-infection: A Systematic Review and Meta- Analysis. Frontiers in Medicine. 2021, 8:681469