How worried should we be about the monkeypox virus found in the UK?

Health authorities in the UK have confirmed a case of monkeypox – a rare viral infection related to smallpox – in a person who recently flew in from Nigeria.

The patient is receiving specialist care in an isolation unit at Guy’s and St Thomas’ infectious disease hospital unit in London, the UK Health Security Agency (UKHSA) said on Saturday.

The UKHSA didn’t release any details about the person’s sex or age but said it was working to identify anyone who has been in close contact with the infected patient, including people who travelled on the same flight.

What are the symptoms of monkeypox?

Monkeypox is a relative of smallpox, a disease which was eradicated in 1980, but is less transmissible, causes milder symptoms and is less deadly.

The illness typically lasts for two to four weeks and symptoms can appear anywhere from five to 21 days after infection.

Monkeypox symptoms usually begin with a mix of fever, headaches, muscle aches, backache, chills, exhaustion, and swollen lymph nodes.

This latter symptom is typically what helps doctors distinguish monkeypox from chickenpox or smallpox, according to the World Health Organization (WHO).

Once you have a fever, the key feature of monkeypox, a nasty rash, tends to develop one to three days later, often starting on the face and then spreading to other parts of the body.

The number of lesions may range from a few to thousands.

The lesions will go through an ugly ripening process, from macules (flat lesions) to papules (raised lesions), vesicles (fluid-filled lesions), then pustules (pus-filled lesions) and then finally scabs (crusty lesions) before eventually falling off.

Why is it called monkeypox?

Monkeypox virus belongs to the Orthopoxvirus genus in the family Poxviridae. It was first discovered in 1958 when two outbreaks of a pox-like disease occurred in lab monkeys kept for research, hence the name.

But monkeys might not be the ones to blame for outbreaks, and the natural reservoir of monkeypox remains unknown, though the WHO says rodents are the most likely.

“In Africa, evidence of monkeypox virus infection has been found in many animals including rope squirrels, tree squirrels, Gambian poached rats, dormice, different species of monkeys,” says the UN health agency.

A child affected by monkeypox receives treatment at a centre of the NGO Doctors Without Borders, in Zomea Kaka, in the Central African Republic, October 18, 2018.CHARLES BOUESSEL / AFP

Where is monkeypox found?

Human monkeypox primarily causes outbreaks in the tropical rainforest regions of Central and West Africa and is not typically seen in Europe.

The Democratic Republic of the Congo (DRC) had the first recorded human case of monkeypox in 1970.

Since then, cases have been reported in 11 African countries: Benin, Cameroon, the Central African Republic, the Democratic Republic of the Congo, Gabon, Ivory Coast, Liberia, Nigeria, the Republic of the Congo, Sierra Leone, and South Sudan.

The first outbreak of monkeypox reported outside of Africa was linked to an importation of infected mammals in 2003 in the United States, according to the US Centers for Disease Control and Prevention (CDC).

More recently, in 2018 and 2019, two travellers from the United Kingdom, one from Israel, and one from Singapore, all with travel history in Nigeria, were diagnosed with monkeypox following a large outbreak there, according to Europe’s own health agency, the European Centre for Disease Prevention and Control (ECDC),

How do you catch monkeypox?

You can catch the virus from the bite or scratch of an infected animal, by eating bush meat, being in direct contact with an infected human or touching contaminated bedding or clothing.

The virus enters the body through skin lesions, the respiratory tract, or the mucous membranes (the eyes, nose, or mouth).

Human-to-human transmission is thought to occur primarily through large respiratory droplets, which generally cannot travel more than a few feet, so prolonged face-to-face contact would be needed.

Should I be worried?

Monkeypox “is usually a mild self-limiting illness and most people recover within a few weeks,” the UKHSA said in its statement confirming the case.

“It is important to emphasise that monkeypox does not spread easily between people and the overall risk to the general public is very low,” said Dr Colin Brown, the agency’s director of clinical and emerging infections.

Although its symptoms are milder than those of smallpox, monkeypox has been shown to cause death in as many as 11 per cent of infected patients compared to about 30 per cent for smallpox, according to the WHO.

Mortality is higher among children and young adults, and immunocompromised individuals are especially at risk of severe disease.

Treatment and prevention

There is currently no specific treatment recommended for monkeypox, and it usually goes away on its own.

Vaccination against smallpox is believed to be highly effective in preventing monkeypox, but because smallpox was declared eradicated more than 40 years ago, first-generation smallpox vaccines are no longer available to the general public.

A newer vaccine developed by Bavarian Nordic for the prevention of smallpox and monkeypox has been approved in the European Union, the United States and Canada (under the trade names Imvanex, Jynneos and Imvamune), and antivirals are also under development.