Two Singapore residents who had been on board a hantavirus-hit cruise ship have tested negative to the rare respiratory disease, according to Singapore’s Communicable Diseases Agency (CDA).

The two men aged 65 and 67 had been on the MV Hondius and also the same flight as a confirmed hantavirus case from St Helena to Johannesburg on April 25, the CDA said a day earlier. The confirmed case did not travel to the city state and died in South Africa.

The CDA’s National Public Health Laboratory conducted testing with “multiple samples collected from the individuals”, that confirmed that hantavirus, including the Andes virus, was “not detected”, it said in a statement late on Friday.

As a precaution, the two men would remain in quarantine for 30 days from the date of last exposure and testing would be conducted again before release from quarantine, CDA added, saying “the risk to the general public in Singapore remains low”.

Both men arrived in Singapore in early May before being isolated and monitored at Singapore’s National Centre for Infectious Diseases.