Influenza is a serious infection which causes substantial morbidity and mortality annually. Research shows that influenza is a major contributor to mortality in the elderly and is associated with cardiovascular events such as stroke and heart attack. Influenza infection in the elderly is more severe than in other age groups, with a higher viral load and longer virus shedding, resulting in higher risk of transmission and more serious illness. Aged care facilities are particularly at risk of outbreaks, which can have catastrophic impacts on residents and staff.
Similarly, COVID-19 causes the most serious morbidity and the highest mortality in older people compared with younger age groups and outbreaks have also occurred in aged care facilities. Given the influenza study has been running since 2018, we now have an opportunity to also study the burden of COVID-19 in aged care facilities. This can inform prevention, control and mitigation of outbreaks in these settings.
A cohort study of residents and staff in nine aged care facilities. Every year from March until October, active surveillance is conducted for clinical respiratory illness. When outbreaks are identified, residents and staff are tested for influenza. From 2020, testing will also be done for COVID-19. Data on baseline sociodemographic and clinical factors, influenza vaccination and aged care facility-specific information is collected. The study is being done as a collaboration between UNSW and Hammondcare, a leading aged care provider in Australia.
We will measure the impact of influenza and COVID-19 in staff and residents of aged care facilities. We will also measure the relative and absolute effectiveness of influenza vaccines in preventing influenza in residents of aged care facilities aged 65 years and over, and measure the impact of influenza vaccine on morbidity and mortality caused by COVID-19.
The study has been running since 2018. Data are being analysed currently on influenza vaccine effectiveness. Two publications have arisen to date:
Tan HY, Lai E, Kunasekaran M, Chughtai AA, Trent M, Poulos CJ, MacIntyre CR. Prevalence and predictors of influenza vaccination among residents of long-term care facilities. Vaccine. 2019 Oct 8;37(43):6329-6335. doi: 10.1016/j.vaccine.2019.09.021. Epub 2019 Sep 13.
Lai E, Tan HY, Kunasekaran M, et al. Influenza vaccine coverage and predictors of vaccination among aged care workers in Sydney Australia.Vaccine. 2020;38(8):1968–1974. doi:10.1016/j.vaccine.2020.01.004
Influenza and COVID-19 can have devastating effects on vulnerable people in aged care facilities, the staff caring for them and their families. Poor control of these infections in aged care can also spill over into community epidemics. Vaccination can be used to control influenza, and we have already identified some barriers to vaccination in aged care facility staff, and been able to compare effectiveness of two influenza vaccines in older people. We are also analysing design features of aged care facilities and their relationship to outbreaks. This research will be able to inform prevention and control strategies in aged care.