The first case of a highly fatal disease transmitted by ticks has been confirmed in South Korea.

The Korea Centers for Disease Control and Prevention said Tuesday that it confirmed the first case of severe fever with thrombocytopenia syndrome (SFTS) in a patient who died last August.

The patient was one of five cases suspected of SFTS during an investigation of people with unidentifiable illnesses.

The disease control agency said that SFTS virus was found in samples taken from the patient. The remaining four cases tested negative for the tick-transmitted disease.

The agency also said that it is working on another suspected case of an elderly man who died in Jeju Island this month. He suffered from fever and diarrhea, and was suspected of being bitten by a tick.