We are living in strange times – locked down, confined to quarters, and socially isolated from friends and family, even with of the technical advantages of the 21^st century at our beck and call.

However, by itself, social isolation is no bad thing. There are people who seek roles in society apart from others – lighthouse keepers for example. For some, to be apart for others is a chance for peace and quiet and solitude. But what if you are socially isolated – with a decreasing network size and limited opportunities for social contact – yet have no wish to be? To become aware of this isolation is to be lonely.

We can define loneliness as “the discrepancy between an individual’s achieved and desired level of social relationships” (Bergefurt et al., 2019), while social relationships are central to our health and wellbeing. In normal times, it is a particular problem of the elderly, a combination of decreasing economic resources, mobility impairment, and the passing of friends and peers.

It is well-known that loneliness leads to increased risk of heart disease, infectious illness, poor responses to stress, loss of cognitive function, and predicts mortality. When it comes to our health, to be socially isolated is at least as important as any other variable (e.g. smoking). Indeed, if two individuals have the same illness – and the same severity of illness – the individual who is lonely is two and a half times more likely to die.

Loneliness is also more prevalent than might be expected, with studies suggesting that a broad range of the general population (17-57%!) report feelings of loneliness, with a contemporary study reporting that 12% of Americans had “no-one with whom to spend their free time”. However, there are several stages of life in which loneliness is more common: late-20s, mid-50s and late-80s. While we are all more vulnerable to feelings of loneliness in the grip of this global pandemic, it is more important than ever before, for all of us to stay in touch with others. Whether it is by telephone, text, social media, Skype (and other variants) or even a good old-fashioned letter, don’t assume that others are coping better than you. Chances are that they are not – and the people who are most vulnerable may not be the ones you think.

As we struggle with coronavirus (COVID-19), be aware that the ones who are most lonely are also the most vulnerable. Their immune system will be less effective. They will be more likely to catch a disease and it will be harder for them to effectively fight it off. Now, more than ever, we must all do what we can to stay in regular touch with friends, older relatives and neighbours. It doesn’t have to be much, but it should be frequent, and enable you to show them you care.

Dr James Jackson is a Senior Lecturer in Biological Psychology at Leeds Trinity University, with research interests that include coping with tinnitus, chronic pain, and stress.