A 42-year-old British man who works as a flight attendant tested positive for the virus on 20 June in Singapore, the health ministry said late on Tuesday.
He is in a stable condition in a ward at the National Centre for Infectious Diseases, it added. Singaporean authorities have identified 13 close contacts of the man who were in touch with him over the last 21 days and have put them under quarantine.
South Korea also joined the southeast Asian country as it reported the first case of the monkeypox virus on Wednesday, prompting the country’s president to direct health authorities to “step up quarantine management for foreign entrants”.
President Yoon Suk-yeol also ordered the officials “to be fully prepared to distribute vaccines and treatments to the medical field”.
The infected person, identified as a Korean national, is receiving treatment at the Incheon Medical Center after he displayed symptoms while entering the country from Germany on Tuesday.
Health authorities have pledged to strengthen monitoring and response systems, by designating areas that require strengthened quarantine management.
The Korea Disease Control and Prevention agency (KDCA) also raised the alert level to “caution” for infectious disease, the second of the country’s four levels, upon confirmation of the virus case.
“The KDCA has been pushing for utilising secured [monkeypox] vaccines and treatments ... and additional introduction of those, while the agency is continuously expanding its diagnostic testing capabilities,” the agency’s commissioner Peck Kyong-ran said.
“Among those who have been exposed [to monkeypox virus] through physical contact with confirmed patients, those with medium or high risks will receive vaccination under their consent,” Ms Peck said, adding that the country is not reviewing ring vaccination for monkeypox.
Another person, who was also suspected to have monkeypox, tested negative in South Korea on Wednesday.
South Korea in June designated monkeypox as a second-degree infectious disease, according to its four-tier system, with 22 contagious diseases, including Covid-19, cholera and chickenpox, being included in the same category.
Monkeypox is a rare and relatively mild viral infection. It has a six-to-16 day incubation period. Symptoms include a high temperature, headache, a rash, muscle aches, backache, swollen glands, shivering, and exhaustion, according to the NHS.
In recent weeks, more than 1,600 cases of the disease have been reported across the world.
Additional reporting by agencies