SEOUL - South Korea is set to release test results on Thursday on an unidentified virus that has sickened eight, including a pregnant woman who died on Tuesday, local media reported Wednesday.

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After the woman, 36 years old and nine months pregnant, died Tuesday of pneumonia related to the unidentified virus, the Center for Disease Control (CDC) has been studying to figure out the virus suspected to have caused her pneumonia.

The CDC said the test results will come out on Thursday, local media reported. The CDC added that more time would take to determine the exact cause as it takes eight weeks to get results from genetic tests.

The death of the pregnant woman marked the first mortality caused by the unidentified virus. Including the woman who died, seven of the eight patients have recently given birth or are expecting.