China's top respiratory disease expert on Thursday predicted gaining "basic control" over the new-coronavirus outbreak by the end of April, as the country recorded its lowest death toll in nearly a month.

Zhong Nanshan, who heads a high-level expert team at the National Health Commission, told a press conference in the southern city of Guangzhou that the outbreak in China has not yet peaked but should between the middle and end of February.

Given that the number of daily new infections has been on a downward trend, Zhong said, "We are confident that we will have basic control by the end of April."

The number of deaths on the mainland has risen by 29 to 2,744, with confirmed infections increasing by 433 to 78,497, the commission said Thursday.

Among deaths in the 24 hours to the end of Wednesday, 26 were in the central province of Hubei, the epicenter of the epidemic, and one each in Beijing, Heilongjiang Province and Henan Province. The number of new infections in Hubei rose to 409 from 401 a day earlier.

Despite the downward trend in the number of daily new infections, health authorities in the southern province of Guangdong have said 14 percent of COVID-19 patients discharged from hospital after recovering have tested positive again.

Regarding these cases, Zhong said that while it is impossible to draw a clear conclusion, the general infection rule that those who develop sufficient antibodies should not be infected again should still apply.

"Right now, the important thing is not whether patients will be re-infected but whether they will transmit the infection to others."

Current epidemiological data show that one person can infect two to three people, with patients in severe condition being more contagious, he added.

The virus is widely believed to have originated in Wuhan, the capital of Hubei, but Zhong suggested that the virus may have a different origin, given the rising number of infections outside China.

"The first case of novel coronavirus pneumonia was reported in China, but that does not necessarily mean it originated in China," he said, adding, experts initially only thought of China without considering other countries as a possible source.

As the virus spreads in South Korea and Japan, some Chinese cities, such as Beijing, have tightened restrictions on travelers from those countries by imposing 14-day quarantines.

After easing two-week quarantine rules for travelers from other countries just last week, the Beijing municipal government said Wednesday visitors from "countries with severe outbreaks" must undergo quarantine at home or in centralized medical facilities upon arrival.

The announcement by the capital's health committee cited concerns over increasing infections abroad, particularly in Japan and South Korea.

In some parts of Beijing, apartment building managers told returning Japanese to self-quarantine, the Japanese Embassy in Beijing said in a newsletter on Thursday.

Yancheng, a city in Jiangsu Province in eastern China that is home to a Kia Motors Corp. factory, decided Tuesday to require all South Koreans to undergo observation at a designated hotel upon arrival.

Weihai, a city in the eastern province of Shandong, has opted for a similar move, telling all travelers from South Korea and Japan to undergo a two-week quarantine at a designated hotel, according to local media.

Meanwhile, neighboring Yantai city on Wednesday introduced separate corridors at its airport for passengers flying in from neighboring countries and said it will begin virus tests for all passengers arriving from abroad.

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