Health bosses confirmed a total of 20 cases of the disease have been found in the country so far.
The UK Health Security Agency (UKHSA) guidance now recommends that people who have had ‘unprotected direct contact or high-risk environmental contact’ should isolate.
Those who are considered at high risk of having caught monkeypox may have had household contact, sexual contact, or have changed an infected person’s bedding without wearing appropriate PPE.
UKHSA also advises that they are offered a smallpox vaccine.
The guidance comes after Dr Susan Hopkins, chief medical adviser for UKHSA, warned that monkeypox is spreading through community transmission.
Dr Hopkins said updated figures for the weekend will be given on Monday as she warned of more cases ‘on a daily basis’.
But what are the symptoms of the infection?
Here’s all you need to know:
What are the symptoms of monkeypox?
According to the NHS, the following are the first symptoms of monkeypox:
- a high temperature
- a headache
- muscle aches
- swollen glands
- shivering (chills)
A rash usually appears 1 to 5 days after the first symptoms. The rash often begins on the face, then spreads to other parts of the body.
How long do symptoms last?
Monkeypox symptoms usually clear up in 2 to 4 weeks.
Should you isolate if you are a close contact of someone with monkeypox?
UKHSA is advising close contacts of monkeypox cases to isolate for three weeks.
This includes no travel, providing details for contact tracing and avoiding direct contact with immunosuppressed people, pregnant women and children under 12.
How is monkeypox treated?
If you have monkeypox you'll usually need to stay in a specialist hospital, so the infection does not spread to other people and your symptoms can be treated.
Treatment for monkeypox aims to relieve symptoms. The illness is usually mild and most people recover in 2 to 4 weeks.
How is monkeypox spread?
The disease, first found in monkeys, can be transmitted from person to person through close physical contact, including sexual intercourse, and is caused by the monkeypox virus.
Dr Hopkins warned that doctors are seeing community transmission, with cases predominantly being identified in individuals who self-identify as gay or bisexual or men who have sex with other men.
She said: ‘We are detecting more cases on a daily basis and I’d like to thank all of those people who are coming forward for testing to sexual health clinics, to the GPs and emergency department.’
Asked if there is community transmission in the UK, she said: ‘Absolutely, we are finding cases that have no identified contact with an individual from west Africa, which is what we’ve seen previously in this country.
‘The community transmission is largely centred in urban areas and we are predominantly seeing it in individuals who self-identify as gay or bisexual, or other men who have sex with men.’
Asked why it is being found in that demographic, she said: ‘That’s because of the frequent close contacts they may have.
‘We would recommend to anyone who is having changes in sex partners regularly, or having close contact with individuals that they don’t know, to come forward if they develop a rash.’
Is there a vaccine?
Dr Hopkins said: ‘There is no direct vaccine for monkeypox but we are using a form of smallpox vaccine – a third-generation, smallpox vaccine that is safe in individuals who are contacts of cases.
‘So we’re not using it in the general population.
‘We’re using it in individuals who we believe are at high risk of developing symptoms, and using it early, particularly within four or five days of the case developing symptoms.
‘For contacts, (this) reduces your risk of developing disease, so that’s how we’re focusing our vaccination efforts at this point.’