A rare disease that's related to smallpox has shown up in the United Kingdom for the first time.
The disease, called monkeypox, was diagnosed in a person staying at a naval base in Cornwall, England, according to a statement issued Saturday (Sept. 8) by Public Health England, the U.K. health agency investigating the case. "This is the first time this infection has been diagnosed in the United Kingdom," the statement said.
The patient is from Nigeria and is believed to have contracted the infection there before traveling to the U.K. on a flight in early September, according to the BBC.
U.K. officials are now working to track down and notify people who may have been in close contact with the patient, including some people who traveled on the same flight as the patient to the U.K. [27 Devastating Infectious Diseases]
But experts emphasized that, despite its relation to the notoriously deadly smallpox, monkeypox is actually a very mild illness, and it doesn't spread easily between people.
"It's not spread readily at all. In fact, it's rather hard to spread," said Dr. William Schaffner, an infectious-disease specialist at Vanderbilt University Medical Center in Nashville, Tennessee, who is not involved with the U.K. case. "[Monkeypox] requires rather close contact for transmission, usually over a prolonged period," Schaffner said. "That's extremely reassuring" for a case like this, he added.
A rare disease
Monkeypox is a rare viral disease that occurs mostly in remote parts of central and west Africa, according to the World Health Organization (WHO). The virus lives in animals, including primates and rodents, but can sometimes "jump" from animals to people, the WHO says.
Both monkeypox and smallpox belong to the poxvirus family called orthopoxvirus. Smallpox was declared eradicated from the world in 1980, meaning cases of the disease no longer occur naturally. But human cases of monkeypox continue to occur sporadically. Since 1970, human cases of monkeypox have been reported in 10 African countries, according to the WHO. In 2017, Nigeria experienced its first outbreak of monkeypox since 1978, with 172 suspected cases, the WHO says.
Although monkeypox and smallpox have similar symptoms, monkeypox is less deadly than smallpox: In previous outbreaks, the fatality rate for monkeypox has been between 1 percent and 10 percent, WHO said. In contrast, smallpox had a fatality rate around 30 percent. (During the Nigeria monkeypox outbreak, there was one reported death, of a patient who had a weakened immune system.)
People infected with monkeypox can spread the disease to others, mostly through "large respiratory droplets" that are expelled when a person coughs, sneezes or talks, according to the Centers for Disease Control and Prevention (CDC). These droplets typically can't travel more than a few feet, "so prolonged face-to-face contact is required" to spread the disease, the CDC says People may also become infected through direct contact with bodily fluids or the skin lesions of infected people, or via indirect contact with contaminated clothing.
Symptoms usually appear about two weeks after a person is exposed to monkeypox. Initial symptoms can include fever, headache, loss of appetite, muscle aches and swollen lymph nodes, Schaffner said. Soon after, patients develop a "pox" rash, with lesions that often appear over the face and trunk. The lesions progress to become small, fluid-filled blisters before scabbing over and falling off.
People typically recover after two to four weeks, according to the CDC, although some people may be left with scarring from the rash, Schaffner noted.
Although the illness may be uncomfortable, for the most part, it's a very mild disease, Schaffner told Live Science. "[The] morality rate is very, very low," he said.
Will it spread?
Because the disease is hard to spread, Schaffner speculated that there would be no further cases of monkeypox tied to the U.K. case, expect perhaps in family members who traveled with the patient, if that was the case.
But as a precaution, officials from Public Health England said they were contacting people who had been in close proximity to the patient during the flight, "to ensure that if [others] do become unwell they can be treated quickly," the statement said.
The patient traveled from Nigeria to London on Sept. 2, and anyone who hasn't been contacted yet doesn't need to take further action, the BBC reported.
Schaffner also noted that, because the patient stayed at a naval base, "you can contact absolutely everyone with whom they had contact" with at the base, and monitor them very closely.
The patient is now being treated at the Royal Free Hospital in London. Public Health England did not disclose the patient's age or gender, or whether he or she is a member of the military, according to The Guardian.
Original article on Live Science.
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Rachael is a Live Science contributor, and was a former channel editor and senior writer for Live Science between 2010 and 2022. She has a master's degree in journalism from New York University's Science, Health and Environmental Reporting Program. She also holds a B.S. in molecular biology and an M.S. in biology from the University of California, San Diego. Her work has appeared in Scienceline, The Washington Post and Scientific American.