TAIPEI — Chinese public health authorities are taking precautions to prevent a bubonic plague outbreak in a remote northern region after a herder contracted the disease, although experts say the risk is low given the limited number of cases so far and the availability of modern medicine.
The health commission in Bayannur in Inner Mongolia raised its public health warning to its third-highest of four alert levels on Sunday and banned the hunting, skinning, and transportation of rodents that might carry the bacteria, known as Yersinia pestis. The municipal government raised its alert level by one notch to ‘‘standard plague outbreak alert,’’ which means humans have been infected.
‘‘There is a risk of a human plague epidemic spreading in this city,’’ Bayannur’s health commission said in a statement.
Over the past year, China has reported five cases of the disease associated with some of the deadliest pandemics in human history. The plague caused the Black Death that devastated the population of medieval Europe and repeatedly afflicted Asia and more recently Africa, but it has largely been controlled since the mid-20th century.
World Health Organization spokeswoman Margaret Harris told reporters in Geneva on Tuesday that the plague case count in China was low and the agency did not consider it high risk, but it was monitoring the situation with partners in China and Mongolia.
Officials at Inner Mongolia’s regional center for disease control have warned that the plague may have long been circulating locally and that there is risk of human-to-human transmission, according to a statement posted online by the regional government last month.
Under the new measures announced in Bayannur, which will remain in effect until 2021, suspected cases of plague among human patients or sick and dead marmots must be reported immediately. The city of Beijing also urged residents on Monday not to go camping in Inner Mongolia, a vast strip of scenic grassland and desert that urban dwellers often visit.
The precautions against the plague are a reminder of the public health challenges facing Chinese authorities even as the country emerges from COVID-19. Last week, Chinese state-affiliated researchers published a paper warning about a new type of swine flu discovered in pig farmers with the potential to cause a pandemic, causing yet another flurry of international concern.
The plague, which researchers generally believe originated from the Asian steppes, killed tens or hundreds of millions of people in several deadly waves throughout history. One particularly deadly wave in the 14th century traveled along the Mongol Empire’s flourishing trading routes and killed one-third of the population in Europe.
Today, the disease continues to circulate regularly in many parts of the world but usually does not spark major epidemics or public health crises. Madagascar suffered several notable outbreaks in recent years that killed hundreds. The United States averages about seven cases a year, according to the Centers for Disease Control. Officials in China say they had about 30 cases in the last decade.
Carried by rats and fleas, plague is usually treatable with antibiotics in its ‘‘bubonic’’ form, which attacks lymph nodes and causes fevers and boils. But the disease can lead to quick death if the bacteria infect the respiratory system or bloodstream in rarer conditions known as pneumonic and septicemic plague.
China’s National Health Commission said it found five plague diagnoses since last year; four patients came from Inner Mongolia and recovered normally while one man in Gansu province died. Chinese authorities have not released details about the causes or circumstances of the cases.
In the adjacent country of Mongolia, farther north, two herders died last year after eating marmot meat and contracting the disease.
Chen Zhengming, an epidemiologist and China program leader at Oxford University’s population health school, said the plague has long existed in Inner Mongolia and posed limited risk.
‘‘From time to time the sporadic outbreak does occur in remote areas and China, mainly through its C.D.C. systems, has good response systems and experience in containing them rapidly,’’ he said.
The plague case, which was covered widely by the media in Beijing this week, was not the only health scare to emerge in recent weeks in China. The central government — and some international experts — called for calm after Chinese researchers reported that a new variation of the H1N1 swine flu, called G4, has ‘‘the essential hallmarks of a candidate pandemic virus’’ and has already been found in some pig farmers.
The paper was published last week in the Proceedings of the National Academy of Sciences and written by a team of veterinary researchers and epidemiologists including George Gao, head of China’s Center for Disease Control.
White House coronavirus adviser Anthony Fauci testified in the Senate that US officials were ‘‘keeping an eye’’ on the newly reported G4 virus, but said he did not consider it an immediate threat.