MANILA - Health officials have cleared 10 out of 11 people who earlier showed signs of infections from the deadly Middle East Respiratory Syndrome-Coronavirus (MERS-CoV).
All 11 of them tested negative, but one was considered a "probable cause" and held for further tests.
A passenger who flew in with the index patient - a 32-year-old Filipino nurse returning from Saudi Arabia - is also regarded as a MERS-CoV suspect.
The nurse who tested positive for MERS-CoV is still being treated. She is five weeks pregnant. Health officials have assured her the baby is unlikely to be infected.
The nurse arrived in the Philippines on Feb 1 without showing symptoms associated with MERS-CoV, a deadly strain of the coronavirus that causes severe respiratory illness.
A day after her arrival, however, she experienced flu-like symptoms. Three tests confirmed that she had MERS-CoV, the first case to be diagnosed in the Philippines.
Two passengers who were with her on board Saudi Airline Flight 860 have been placed in isolation.
"One is considered a 'patient under investigation' and another one is considered a (MERS-CoV) suspect," said Dr Lyndon Lee Suy, the healthy ministry's spokesman.
The health ministry reported that it has contacted 115 of the 225 passengers who travelled with the index patient, and they are being tested for MERS-CoV.
All 56 people who had close contact with the nurse will remain quarantined till Feb 24, the health ministry said. Most of them are staff members of the Evangelista Medical Safety Hospital where the nurse first sought medical attention on Feb 2.
The Philippines recorded its first case of MERS-CoV on home soil in April last year: A Filipino nurse who had come into contact with a Filipino paramedic who died in the United Arab Emirates.
Another Filipino nurse tested positive for the virus last September.
Both were diagnosed abroad but treated in the Philippines. Both have since recovered.
The foreign ministry said at least six Filipinos have died of MERS-CoV in the Middle East.
MERS-CoV has infected 978 people and killed at least 358 as of Feb 13, according to the World Health Organisation. The first case was reported in Saudi Arabia in 2012, and most infections have been detected in countries in and near the Arabian peninsula.