* New cases lowest since Jan. 20
* Domestic spread of virus significantly slower
* Imported cases rising
* Shanghai Disneyland to partially reopen (Adds law commission comment, Wuhan airport, Shanghai Disneyland)
BEIJING/SHANGHAI, March 9 (Reuters) - Mainland China, outside Hubei province, reported no new locally transmitted cases for the second straight day, as a senior Communist Party offical warned against reducing vigilance against the disease and of the risk of social stability.
"We must stay cautious, not be blindly optimistic and must not have war-weariness...," said Chen Yixin, secretary general of the Communist Party's Politics and Law Commission.
"We should not reduce the vigilance against the epidemic and the requirements of prevention and control."
China had 40 new confirmed cases of coronavirus infections on Sunday, the National Health Commission said on Monday, down from 44 cases a day earlier, and the lowest number since the health authority started publishing nationwide data on Jan. 20.
Of the new cases on Sunday, 36 were new infections in Wuhan, the provincial capital of Hubei, while the remaining four in Gansu province were imported from Iran.
The total number of imported cases hit 67, including the four Gansu cases.
The new cases on Sunday bring the total accumulated number of confirmed cases in mainland China to 80,735.
While the domestic spread of the virus has significantly slowed in recent days, authorities continue to be mindful of risks stemming from people - foreigners and Chinese nationals - travelling back to China from affected regions.
Shanghai stepped up airport screening over the weekend as imported coronavirus infections from countries such as Italy and Iran emerged as the biggest source of imported cases in China.
China is also conscious of the tens of millions of migrant workers returning to offices, malls and factories and the potential transmission risks.
Chen acknowledged that while the coronavirus outbreak in Wuhan is improving, control and prevention work is still arduous, according to a statement posted on the commission's Wechat account on Monday.
Huge epidemics may bring risk to social stability, he said, recommending that the government take precautions and make early plans to ensure peace and stability in society.
Public spaces and amenities are showing signs of resuming operations.
Wuhan's Tianhe International Airport said in a statement on its Weibo microblog that it was preparing to resume work, taking measures such as staff training, equipment maintenance and security inspections. However this does not indicate a specific date for resuming commercial operations has been determined.
Meanwhile, Walt Disney Co's Shanghai Disneyland said on Monday it will resume a limited number of operations at its resort as part of the first step of a phased reopening, though the main theme park will remain shut.
It said that a limited number of shopping, dining, and recreational activities would be available at Disneytown, Wishing Star Park and Shanghai Disneyland Hotel though they will operate under limited capacity and reduced hours of operation. The resort had been closed since Jan. 25 amid the virus outbreak.
As of the end of Sunday, 58,600 patients had been discharged from Chinese hospitals. Authorities are aware of the potential for re-infection, and have told recently recovered patients to go into quarantine for 14 days after being discharged.
On Saturday, a small hotel used to quarantine people under observation in Fujian province collapsed, killing 10.
Of the 71 people inside the hotel in Quangzhou city at the time of the collapse, 58 had been under quarantine, the Quangzhou city government said.
The death toll from the outbreak in mainland China reached 3,119 as of the end of Sunday, up 22 from the previous day.
Hubei, the epicentre of the outbreak, reported 21 new deaths. In Wuhan, 18 people died.
Total deaths outside of mainland China have surpassed 500, with the number of fatalities dominated by Italy and Iran. Cases continue to rise in other countries, including the United States. (Reporting by Ryan Woo, Sophie Yu, Lusha Zhang, Brenda Goh and Emily Chow; Editing by Himani Sarkar, Gerry Doyle and Michael Perry)