South Korea has reported 334 additional cases of the new coronavirus, raising the country's total tally to 1,595, the highest number outside China.

The Korea Centres for Disease Control and Prevention (KCDC) said 307 of the new cases were in the south-eastern city of Daegu, home to the church at the centre of the country's outbreak.

The daily figure is the largest reported spike in the country since its first case was confirmed on January 20.

South Korea also reported its 13th death linked to the virus.

South Korea reported its first case on January 20 and is second behind China in the number of infections. ( AP: Jin Yeon-soo )

Daegu reported 307 of the new cases, the KCDC said in a statement.

The south-eastern city is where a church that was at the centre of the outbreak is located.

Military drills involving troops from South Korea and the United States have been postponed until further notice, with soldiers from both countries among those infected.

The US military reported its first case of the coronavirus on Wednesday, in a 23-year-old soldier based in Camp Carroll, about 20 kilometres from Daegu.

The South Korean military has also reported at least 21 infections and has confined most troops to their bases.

There are around 28,500 US troops stationed in South Korea, which remains technically at war with North Korea.

Infected Korean flight attendant 'flew to Los Angeles'

On Thursday, local media reported that a Korean Air flight attendant who has tested positive for coronavirus had worked on flights between Seoul and Los Angeles.

The KCDC said the crew member had been on a Korean Air KE958 flight from Israel to Incheon on February 15.

Local media reported that an infected Korean Air flight attendant worked on a flight to Los Angeles on February 15. ( Reuters: Heo Ran )

The passengers included a South Korea tour group from which 31 coronavirus cases were seen to have originated.

Some 30 crew members who were on the same flights with her have self-quarantined for 14 days, media reports said.

The number of new cases being officially reported outside China has exceeded those reported by Beijing for the first time since the outbreak began.

On Wednesday, the World Health Organisation (WHO) said 459 new cases had been reported by 37 countries over the past 24 hours, compared with 412 by China.

"The sudden increases of cases in Italy, the Islamic Republic of Iran and the Republic of Korea are deeply concerning," WHO director-general Tedros Adhanom Ghebreyesus said.

About 81,000 people around the globe have now been infected by the coronavirus.

More than 2,700 people have died since the outbreak began in December.

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