What is monkeypox and should you be worried?

With monkeypox being detected in countries from the US to Australia and France to the UK, we take a look at the situation and whether it is cause for concern.

What is monkeypox?

Monkeypox is a viral infection typically found in central and western Africa. Cases, usually small clusters or isolated infections, are sometimes diagnosed in other countries, including the UK where the first case was recorded in 2018 in an individual thought to have contracted the virus in Nigeria.

There are two forms of monkeypox, a milder west African strain and a more severe central African, or Congo strain. In Australia and the UK at least, it is thought the recently diagnosed individuals have the west African strain, although not all countries have released such information.

According to the UK Health Security Agency, early symptoms of monkeypox include fever, headache, muscle aches, swollen lymph nodes and chills, as well as other features such as exhaustion.

“A rash can develop, often beginning on the face, then spreading to other parts of the body, including the genitals,” the UKHSA says. “The rash changes and goes through different stages, and can look like chickenpox or syphilis, before finally forming a scab, which later falls off.”

Most patients recover from monkeypox in a few weeks.

How is it spread?

Monkeypox does not spread easily between humans, and requires close contact. According to the US Centers for Disease Control and Prevention, it is thought that human-to-human transmission primarily occurs through large respiratory droplets.

“Respiratory droplets generally cannot travel more than a few feet, so prolonged face-to-face contact is required,” the CDC says. “Other human-to-human methods of transmission include direct contact with body fluids or lesion material, and indirect contact with lesion material, such as through contaminated clothing or linens.”

Where have recent cases been found?

Monkeypox cases have been confirmed in recent weeks in a number of countries where it is not endemic, including the US, Canada, Italy, Portugal and Sweden, with the first cases reported in Germany and Australia on Friday. Suspected cases have been identified in Spain and France.

While some cases have been found in people who have recently travelled to Africa, others have not: of the two Australian cases to date, one was in a man who had recently returned from Europe, while the other was in a man who had recently been to the UK. A case in the US meanwhile appears to be in a man who recently travelled to Canada.

The UK is also experiencing cases of monkeypox, with signs that it is spreading in the community. So far 20 cases have been confirmed, with the first reported on 7 May in a patient who had recently travelled to Nigeria.

Not all of the cases appear to be linked and some have been diagnosed in men who self-identify as gay, bisexual, or men who have sex with men.

The World Health Organization said on Tuesday that it was now coordinating with European health officials.

Does this mean monkeypox is sexually transmitted?

Dr Michael Head, a senior research fellow in global health at the University of Southampton, says the latest cases may be the first time transmission of monkeypox though sexual contact has been documented, but this has not been confirmed, and in any case it is probably close contact that matters.

“There is no evidence that it is a sexually transmitted virus, such as HIV,” Head says. “It’s more that here the close contact during sexual or intimate activity, including prolonged skin-to-skin contact, may be the key factor during transmission.”

The UKHSA is advising gay and bisexual men, as well as other communities of men who have sex with men, to look out for unusual rashes or lesions on any part of their body, in particular their genitalia. “Anyone with concerns that they could be infected with monkeypox is advised to make contact with clinics ahead of their visit,” the UKHSA says.

How concerned should we be?

At present, the answer seems to be not very. Experts have suggested it is unlikely there will be very large outbreaks, although it is important contacts of those infected are identified.

Dr Susan Hopkins, the chief medical adviser at UKHSA, calls the situation “rare and unusual” but adds: “UKHSA is rapidly investigating the source of these infections because the evidence suggests that there may be transmission of the monkeypox virus in the community, spread by close contact.”

On Friday, it emerged that the UK had bought supplies of a vaccine against smallpox – a related but more severe virus that has been eradicated. According to the World Health Organization, “vaccination against smallpox was demonstrated through several observational studies to be about 85% effective in preventing monkeypox”. The jab may help to prevent monkeypox, or reduce the severity of illness.

Reports suggest the vaccine has already been offered to healthcare workers in the UK, although it is unclear how many have been vaccinated.

A UKHSA spokesperson said: “Those who have required the vaccine have been offered it.”

Spain has also been rumoured to be looking to buy supplies of the vaccine, while other countries – such as the US – have large stockpiles of the jabs.