OBJECTIVES : Following the Covid-19 pandemic, the World Health Organization (WHO) issued target product profiles (TPP) for Covid-19 vaccines. Assuming SARS-CoV-2 would become recurrent and seasonal, the aim of this study was to conduct an early assessment of the public health impact of a Covid-19 vaccine in the French population aged 65 years and over.

METHODS : A static decision tree model was developed to assess the benefits of a Covid-19 vaccine versus a no vaccine strategy in the French elderly population. The study was conducted under a public health perspective and considered a six-month time horizon. Covid-19 clinical outcomes were collected from recently published literature on SARS-CoV-2 and governmental sources and cover the period from February to July 2020. The model outcomes were: Covid-19-related cases, medical visits, emergency department (ED) visits, hospitalizations, ICU admissions, deaths, and number needed to vaccinate (NNV). A 6.6% attack rate was considered based on the Covid-19 outbreak that occurred on the Diamond Princess cruise ship. Vaccine characteristics were based on the WHO TPP, with a steady 70% efficacy over one year against Covid-19 cases and hospitalizations, and an assumed 50% coverage rate. Scenario analyses testing alternative values were implemented.

RESULTS : The vaccine strategy would prevent 311,022 Covid-19 cases, 2,856 medical visits, 18,450 ED visits, 20,823 hospitalizations, 5,677 ICU admissions and 5,727 deaths. The NNV to avoid one case and one hospitalization were 44 and 647 respectively. Increasing coverage rate to 75% was the most impactful scenario with 466,534 cases and 31,234 hospitalizations averted.

CONCLUSIONS : Our study provides preliminary results of the benefits of a potential Covid-19 vaccine following the WHO TPP from a public health perspective. However, the pandemic is still ongoing and further research on the virus characteristics and epidemiology are required to confirm the benefits of a vaccine.