Japan's government says a man treated for pneumonia after returning from China has tested positive for the new coronavirus identified as a possible cause of an outbreak in the Chinese city of Wuhan.
The man became sick while in Wuhan earlier this month, and tests this week found the same virus as detected in Wuhan.
Officials in Wuhan said last weekend that 41 people had pneumonia caused by the new virus and a 61-year-old man had died in China's first known death from the virus.
The outbreak comes just ahead of the lunar new year when many Chinese travel. Officials say the virus is not considered highly contagious.
Elsewhere, German researchers said Thursday they have developed the first diagnostic test for a new virus that has emerged in central China.
The virus was first detected in the Chinese city of Wuhan last year and cases have since also been reported in Thailand.
Faster diagnostic test created
Dr. Christian Drosten, the director of the Institute for Virology at Berlin's Charite hospital, said the test developed by his team will allow labs to reliably diagnose the so-called novel coronavirus "in a very short period of time."
The test protocol is being made available through the World Health Organization, and laboratories can order a molecule from the German team to compare patient samples with a positive control, he said.
"We have just started receiving orders and are now starting to post the molecule," Drosten told The Associated Press.
So far, doctors have only been able to perform a general virus test and then had to sequence and interpret the genome, said Drosten. Large, well-equipped public laboratories are able to do this but smaller labs would struggle to do so, he added.
"We're more concerned about labs in countries where it's not that easy to transport samples or staff aren't trained that thoroughly, or if there is a large number of patients who have to be tested," said Drosten, citing the epidemic of SARS, or Severe Acute Respiratory Syndrome, which killed hundreds in 2002 and 2003.
Drosten, who was one of the co-discoverers of SARS, said the two viruses are so closely related that laboratories which have control samples for SARS in stock can use it to diagnose the new virus, cutting the time required to create a functioning test.