A 75-year-old Omani man who was diagnosed with the first-ever case of Middle East Respiratory Syndrome (MERS) in Thailand was declared virus-free, local media reported Monday, citing the Thai Ministry of Public Health.

The man, who had traveled to Bangkok to treat a heart condition on June 15, was confirmed to have MERS three days after admission to the hospital.

The patient’s condition has significantly improved, the Bangkok Post newspaper said.

All 159 people quarantined in connection to the only Thai MERS case, including the patient’s three relatives, show no signs of infection. They will remain in quarantine until Thursday, according to the daily.

MERS is a viral respiratory disease caused by the MERS-coronavirus. The infection was first reported in 2012 in Saudi Arabia and subsequently spread to other countries.

South Korea has suffered the most from the MERS outbreak.

As of Monday, the South Korean Health Ministry has registered 32 deaths from the current MERS outbreak in the country which began in May. The number of confirmed cases stands at 182, while almost 2,700 people are in quarantine.