Plague control and prevention in Xiliin Gol League faces harsh challenges, and local authorities should make all out efforts to ensure the disease does not spread, the top official of the league said.

Luo Hu, Party chief of Xiliin Gol League, made the remarks on plague control and prevention during an inspection of local medical institutions on Sunday and Monday, following three confirmed cases.

A herding couple from the league, located in the Inner Mongolia autonomous region, were diagnosed with pneumonic plague in Beijing on Nov 12. They are still in critical condition, according to the Beijing Municipal Health Commission.

All those who had close contact with the two patients in Beijing were released from medical observation on Thursday morning, the commission said.

The third case, a 55-year-old male quarry worker, was diagnosed with bubonic plague on Saturday. He is receiving treatment at a hospital in Ulaanqab and is in stable condition, according to the region's health commission.

Ten days before the diagnosis, the patient caught a wild rabbit near the boiler of the mine where he worked in Xianghuang Banner. He skinned and cooked the rabbit, then shared it with three other workers.

Thirteen people who had close contact with the patient are under quarantine for medical observation and are in stable condition, the banner's publicity department said on Thursday.

The third case was unrelated to the previous two cases, according to the region's health commission.

Luo, the top official of Xiliin Gol, urged local authorities to intensify efforts on plague control and prevention, including making more detailed working plans; strictly carrying out disease monitoring, warning, reporting and pre-checking procedures; and controlling potential sources of infection.

He called for a thorough mice and flea elimination campaign in key areas, such as around the houses of herds-people. Diagnosis and treatment in medical institutions should also be improved.

The government of Xianghuang Banner has designated an area of 2.3 square kilometers as the epidemic area, and strict sterilization measures have been applied in the area for disease control and prevention.

Aside from the 13 close contacts, all other 92 employees of the mine where the third case occurred have taken preventive medicine against plague. They check their body temperatures four times every day, and none of them showed abnormalities as of Thursday, according to local health authorities.

Monitoring of plague among animals in the banner, covering 2,200 square km, has been intensified. Further, 15 suspicious wild animal carcasses have been properly disposed of since Nov 13.

In addition, two mice and flea elimination efforts have been applied within 1.5 km of the boiler of the mine, according to the local government.

Authorities have issued 400 kilograms of poisonous bait to local residents to help them eliminate rats and fleas in and around their residences.

Fever clinics are open at three hospitals and four health centers in the banner to help identify suspected plague cases as early as possible.

Of all the 1,322 people who have received tests, only one displayed fever, but the possibility of plague has been ruled out.

The banner will continue to improve plague control and prevention efforts, including improving monitoring, continuing to closely observe people who have been in contact with the patient and making preparations so any suspicious cases can be transferred to hospitals for treatment as soon as possible, the government said.