China has declared a health emergency over Black death plague after a three-year-old boy was struck down by the disease.

The child, from a remote village in Menghai county, Yunnan, was confirmed to be infected by the killer disease on Monday according to Chinese state media reports.

Bubonic plague is a bacterial disease spread by fleas living on wild rodents and can kill an adult in less than 24 hours if not treated in time.

Chinese authorities have now started a level IV emergency response to prevent another epidemic following the Covid-19 outbreak.

The development comes after the discovery of three dead disease-ridden rats in a village in Menghai, China.

Also known as the 'Black Death', the disease killed up to 200 million people in the 14 century according to WHO records.

In Mongolia, China's neighboring country, there has been a Plague outbreak which has seen 22 reported cases, six of which have been confirmed.

A 25-year-old woman was reportedly hospitalised with the disease after eating an infected rodent called a marmot. Three of the six confirmed cases have died in Mongolia - most recently a 38-year-old man in Khovsgol province earlier this month.
Hunting marmots is illegal in Mongolia, but many regard the rodent as a delicacy and kill it for meat.

The Black Death was an epidemic of bubonic plague which struck Europe and Asia in the 13th century killing more than 20 million people in Europe - almost one third of the continent's population between 1347-1352.

Advancements in modern medicine mean a similar pandemic is highly unlikely as it can now be easily treated, if caught.
The bacteria can travel through the air as well as through the bites of infected fleas and rats.Bubonic plague can cause swelling of the lymph nodes.If untreated it could spread to the blood and lungs.Other symptoms included fever, vomiting and chills.