The latest government advice is that everyone in the UK should suspend all "non-essential contact with others" - but what measures are being taken and what advice is there for looking after older and elderly people?
Can I visit older people in their own homes?
The government advises that, by the weekend, groups particularly vulnerable to Covid-19 - such as those over the age of 70 - will be asked to stay at home for 12 weeks.
If you are visiting an elderly relative for an essential purpose, you should "keep a bit more distance, preferably at least 1m [3ft] apart, no kissing and hugging, sadly, and those hand hygiene practices are incredibly important", says Caroline Abrahams, charity director at Age UK.
Age UK adds that if people are worried about visiting the elderly at home, they can always maintain contact via the phone, post or online.
What are care homes doing?
Prime Minister Boris Johnson has said nobody should visit care homes unnecessarily - but stopped short of saying people must not visit relatives in care homes under any circumstances.
Meanwhile, government advice online states anyone who has a new continuous cough or high temperature should not visit care homes and should instead self-isolate.
People who are "generally unwell" should also stay away from care homes, according to the advice.
It adds, however, care homes should consider the "positive impact of seeing friends and family" when reviewing their visitor policies.
Any visitors travelling to care homes for essential purposes must practise good hygiene, the government says.
What if you are worried about someone's mental health?
Mental health charity Mind has tips for those who may be alone or worried about the virus, including putting extra photos up of people you care about, and limiting how long you read the news.
It says elderly relatives could also be encouraged to:
There are also steps to help prevent loneliness in those avoiding contact or staying at home.
Olivia Field, loneliness lead at the British Red Cross, says those staying at home should make sure they find time to do things they enjoy, such as watching TV, reading, writing, art or cooking.
"Ensuring you feel stimulated and have fun protects against loneliness and improves your general wellbeing," she says.
"Remember there are other ways to connect with friends and family - for example, phone, email, social media.
"Talking to people about your worries, about feeling lonely, or simply just about your day, helps."
What else can we do?
Age UK stresses it is also important to think of "practical" ways to help, such as running errands on relatives' behalf or picking up supplies such as food and medication.
Simon Hewett-Avison, from charity Independent Age, also says families need to make sure elderly people have the supplies they need but urges a "balanced approach" rather than panicked stockpiling.
Both the government and supermarkets have urged people not to stockpile goods.
Carers UK says those who cannot visit elderly relatives should think of other ways of spending time together - setting up a family group chat, for example, or playing games online.
"If online communication isn't possible, never underestimate the value of a regular simple phone call to offer social contact and support," it says.
Families and carers should also consider contingency plans if the situation changes, the charity says, such as arranging for a trusted neighbour to help an elderly relative if they are unable to.
If you have concerns about an elderly relative's health or need more information about coronavirus, you can visit the NHS 111 website.
Older people and their families can also call Age UK Advice for free on 0800 169 65 65.
Finally, Age UK says while advice and circumstances could change in the weeks and months ahead, the need for support will remain constant.
"Now is not the time to back off our older population, who need our love and support more than ever," Ms Abrahams says.
"Do provide reassurance and now's a good time to make a plan together as a family."