Image copyright Getty Images Image caption The two victims had eaten raw marmot meat and kidney

A quarantine imposed in Mongolia after two people died from the bubonic plague has been lifted, allowing a number of tourists to leave the area.

The Mongolian couple contracted the illness after eating the raw meat of a marmot, a type of rodent.

Following their deaths, a six-day quarantine was declared on 1 May in Mongolia's western Bayan Olgii province bordering both China and Russia.

In previous centuries plague outbreaks killed millions in Europe and Asia.

Human cases are now rare but can still be deadly unless treated with antibiotics.

What happened?

The couple had eaten raw marmot meat and kidney, thought to be a folk remedy for good health, Ariuntuya Ochirpurev of the World Health Organisation (WHO) in Ulaanbaatar told the BBC.

Suspicion the two victims had developed the highly contagious pneumonic plague led to the decision to impose the quarantine, Ms Ochirpurev added.

The rodent is a known carrier of the plague bacteria and it is commonly associated with plague cases in the country. Hunting the rodent is illegal.

According to Ms Ochirpurev, 118 people had come into contact with the couple and were isolated and treated with antibiotics for prophylaxis.

Among those were seven foreign tourists from Switzerland, Sweden, Kazakhstan and South Korea.

Media reports, however, put the number of tourists much higher, saying travellers from Russia, Germany and the US were barred from leaving the area due to the quarantine.

"After the quarantine [was announced] not many people, even locals, were in the streets for fear of catching the disease," Sebastian Pique, a US Peace Corps volunteer living in the region, told the AFP news agency.

How dangerous is the plague now?

While rare, the plague still continues to be a threat to humans.

The disease - typically transmitted from animals to humans by fleas - has a 30%-60% fatality rate if left untreated.

Image copyright Science Photo Library Image caption The plague bacteria is still a danger to humans

In Mongolia, one case was reported in 2017 but it was not fatal. In 2016, no cases were reported.

From 1989 to 1997, there were 69 cases in the country and 22 deaths, according to the WHO's Ms Ochirpurev.

The US also still has annual cases of the disease and 12 recorded fatalities since 2000.

In 2015, parts of the Yosemite National Park had to be closed due to an outbreak of the plague.

Symptoms of the plague include high fever, chills, nausea, weakness and swollen lymph nodes in the neck, armpit or groin.

It can be hard to identify in its early stages because symptoms, which usually develop after three to seven days, are flu-like.

There are three main types of plague depending on how the infection manifests. The bubonic plague is characterised by swollen lymph nodes. Pneumonic plague affects the respiratory system. It becomes septicaemic if it is found in the bloodstream.

The Black Death, as it was known at the time, caused about 50 million deaths across Africa, Asia and Europe in the 14th Century.

Its last terrifying outbreak in London was the Great Plague of 1665, which killed about a fifth of the city's inhabitants. In the 19th Century there was a plague outbreak in China and India, which killed more than 12 million.