Why are monkeypox cases rising?

STORY: Why are cases of monkeypox spreading?]

A handful of monkeypox cases have been reported or are suspected in Britain, Portugal, Spain, and the U.S.

The outbreaks are raising alarm because the disease mostly occurs in west and central Africa,

and only very occasionally spreads elsewhere.

Here's what scientists know so far.

Symptoms

Monkeypox is a virus that causes fever and a distinctive bumpy rash.

There are two main strains.

The Congo strain is more severe, with up to 10% mortality,

The West African strain has a fatality rate of 1%.

Jimmy Whitworth is a professor of international public health at the London School of Hygiene and Tropical Medicine.

(SOUNDBITE) (English) PROFESSOR OF INTERNATIONAL PUBLIC HEALTH AT LONDON SCHOOL OF HYGIENE AND TROPICAL MEDICINE, JIMMY WHITWORTH, SAYING: "It usually starts with fever and headache. People feel pretty miserable and tired. They can get swollen glands. And then this typical rash develops, which is sort of pustular in form. And that's usually what's infectious."

Transmission

The virus was first found in monkeys in 1958, hence the name.

But rodents are now seen as the main source of transmission.

The virus spreads through close contact, both in spillovers from animal hosts and, less commonly, between humans.

Transmission this time is puzzling experts.

That’s because a number of the cases in the UK have no known connection with each other. Only the first case reported on May 6 had recently travelled to Nigeria.

The UK and U.S. health officials also highlighted that the recent cases were predominantly among men who self-identified as gay or bisexual.

Why now?

One likely scenario behind the jump in cases is increased travel after COVID restrictions were lifted.

Monkeypox puts virologists on the alert because it is in the smallpox family, although it causes less serious illness.

Smallpox was eradicated by vaccination in 1980, and the shot has been phased out.

But it also protects against monkeypox.

Some epidemiologists say the winding down of vaccination campaigns has led to a jump in monkeypox cases.

(SOUNDBITE) (English) PROFESSOR OF INTERNATIONAL PUBLIC HEALTH AT LONDON SCHOOL OF HYGIENE AND TROPICAL MEDICINE, JIMMY WHITWORTH, SAYING: "This is quite alarming from a public health point of view and something that we really need to get a grip of and control as as quickly as we can. There's no need to panic here. This is not going to spread and get into the general population and cause an epidemic like the corona virus has. But even so, this is a pretty large cluster of what appears to be quite a large area."