Immunity to Covid-19: March 2023 update
How do our bodies defend against Covid-19? Read how immune responses differ across people, variants, reinfection, vaccination, and current immunisation strategies.

This POSTnote examines how housing, outdoor spaces and transport can be made more age-friendly. It also highlights challenges for designing and delivering age-friendly cities.
Creating age-friendly cities (627 KB , PDF)
By 2050, 89% of the UK’s population will live in cities and 24% will be aged over 65. Older people participate in society in many ways and are estimated to contribute between £40bn and £61bn a year to the UK economy. As the number of older people living in cities increases, there is growing recognition that cities need to become ‘age-friendly’ to help people remain independent and active as they age, and improve the quality of life and health of older people.
Key points in this POSTnote include:
Acknowledgements
POSTnotes are based on literature reviews and interviews with a range of stakeholders and are externally peer reviewed. POST would like to thank interviewees and peer reviewers for kindly giving up their time during the preparation of this briefing, including:
*Denotes people who acted as external reviewers of the briefing.
Creating age-friendly cities (627 KB , PDF)
How do our bodies defend against Covid-19? Read how immune responses differ across people, variants, reinfection, vaccination, and current immunisation strategies.
This POSTnote will analyse available data on recent trends in distress linked to gender identity and lifespan trajectories in children and adults.
This POSTnote will explain plans to improve patient choice in the context of reforming the Mental Health Act.