As countries are affected by coronavirus disease 2019 (COVID-19), the elderly population will soon be told to self-isolate for “a very long time” in the UK, and elsewhere. 1 This attempt to shield the over-70s, and thereby protect over-burdened health systems, comes as worldwide countries enforce lockdowns, curfews, and social isolation to mitigate the spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, it is well known that social isolation among older adults is a “serious public health concern” because of their heightened risk of cardiovascular, autoimmune, neurocognitive, and mental health problems. 2 Santini and colleagues 3 recently demonstrated that social disconnection puts older adults at greater risk of depression and anxiety. If health ministers instruct elderly people to remain home, have groceries and vital medications delivered, and avoid social contact with family and friends, urgent action is needed to mitigate the mental and physical health consequences. Self-isolation will disproportionately affect elderly individuals whose only social contact is out of the home, such as at daycare venues, community centres, and places of worship. Those who do not have close family or friends, and rely on the support of voluntary services or social care, could be placed at additional risk, along with those who are already lonely, isolated, or secluded. Online technologies could be harnessed to provide social support networks and a sense of belonging, 4 although there might be disparities in access to or literacy in digital resources. Interventions could simply involve more frequent telephone contact with significant others, close family and friends, voluntary organisations, or health-care professionals, or community outreach projects providing peer support throughout the enforced isolation. Beyond this, cognitive behavioural therapies could be delivered online to decrease loneliness and improve mental wellbeing. 5 Isolating the elderly might reduce transmission, which is most important to delay the peak in cases, and minimise the spread to high-risk groups. However, adherence to isolation strategies is likely to decrease over time. Such mitigation measures must be effectively timed to prevent transmission, but avoid increasing the morbidity of COVID-19 associated with affective disorders. This effect will be felt greatest in more disadvantaged and marginalised populations, which should be urgently targeted for the implementation of preventive strategies.