CORONAVIRUS/Japanese student with COVID-19 a 'weak positive,' likely not contagious

Taipei, June 25 (CNA) A Japanese woman studying in Taiwan who tested positive for COVID-19 after returning to Japan had low amounts of the virus in her body and was likely not contagious, the Central Epidemic Command Center (CECC) said Thursday.

The CECC revealed on Wednesday that the woman, who is in her 20s and had been studying at a university in southern Taiwan since February, tested positive for COVID-19 after returning to Japan on June 20.

It also acknowledged that she may have been infected in Taiwan.

Taiwan has since examined additional data from her test sample, which had a cycle threshold, or CT value of 37-38 -- a result on the diagnostic threshold which is often referred to as a "weak positive," CECC spokesman Chuang Jen-hsiang (莊人祥) said at a press conference.

Only samples with a CT value under 35 are considered positive in Taiwan, while those over 32 are unlikely to be contagious, Chuang said.

Because of the woman's test results and her lack of symptoms, it is difficult to determine how long ago she was infected, Chuang said, adding that the CECC does not rule out the possibility that she contracted the virus in Taiwan or that the test was a false positive.

Meanwhile, all 123 contacts identified by the CECC as having come into contact with the woman have received COVID-19 tests, of which 109 have come back negative and the results for the remaining 14 are expected on Friday, the CECC said.

Regarding the case's classification, Chuang said Japan may choose to consider it an imported case from Taiwan.

However, based on international practice, it will not be added to Taiwan's total "because we didn't test her," he said.

When asked if the case should be seen, in practical terms, as ending Taiwan's run of more than two months without a domestic infection, Chuang said people can make up their own minds based on the evidence.

The CECC's current focus is on testing the patient's contacts and working to clarify the source of her infection, he said.