TAIPEI (Taiwan News) — A man in Keelung City has been diagnosed with hantavirus, the first case in northern Taiwan this year and the fourth nationwide.

The patient, who is in his 40s, is a restaurant worker in the port city. He started exhibiting symptoms of the disease, including fever, diarrhea, and muscle pain, on April 10.

He was hospitalized on April 11, but the first screening failed to identify the cause of the illness. A second test was conducted on April 27 and led to a confirmed diagnosis of hantavirus on Tuesday (May 5), according to the Centers for Disease Control and Prevention (CDC).

The patient reported seeing rats, the carriers of the virus, at his workplace but said he had not been bitten. Sterilization and pest control have been conducted at locations he has visited, and those who have come into contact with him have not developed any symptoms.

Health authorities in Keelung urged restaurants, hotels, markets, food stalls, and food factories to beef up measures against rodents. Residents are advised to sterilize areas contaminated by rodent excrement with diluted bleach.

Hantavirus is contracted through contact with rodent urine and feces or rodent bites. Symptoms include fever, muscle pain, headache, abdominal pain, and flushing. Some patients experience hemorrhaging, shock, and renal failure.