Singapore’s Ministry of Health (MOH) announced on May 28 that all 22 close contacts of the imported case of monkeypox in Singapore have completed their quarantine, after having been monitored for the maximum incubation period of 21 days from their last date of exposure to the patient. The last close contact completed quarantine on 28 May 2019. All close contacts are well and remain asymptomatic, MOH said.

MOH added that the patient, a 38-year-old Nigerian national who tested positive for monkeypox on 8 May, has recovered and has been assessed to be non-infectious. He was discharged from the National Centre for Infectious Diseases on May24, 2019 and left Singapore on the same day.

Eight other contacts who were assessed to have a low risk of being infected had been put on active surveillance, where they were called twice daily to monitor their health progress. To date, all contacts have reported to be well and asymptomatic. Active surveillance will end on 30 May 2019, said MOH.

Director of Medical Services, Associate Professor Benjamin Ong, said, “Early detection, contact tracing and quarantine of close contacts have enabled us to tackle the monkeypox case in a proactive, swift and coordinated manner. We thank all healthcare staff involved in the diagnosis and management of this case for their dedication and hard work. Singapore must continue to stay vigilant in our fight against infectious disease threats.”

Director of Medical Services, Associate Professor Benjamin Ong, said, “Early detection, contact tracing and quarantine of close contacts have enabled us to tackle the monkeypox case in a proactive, swift and coordinated manner. We thank all healthcare staff involved in the diagnosis and management of this case for their dedication and hard work. Singapore must continue to stay vigilant in our fight against infectious disease threats.”

MOH advised the public to stay vigilant. Travellers to areas affected by monkeypox in Central and Western Africa should take the following precautions:

• Maintain a high standard of personal hygiene, including frequent hand washing after going to the toilet, or when hands are soiled.
• Avoid direct contact with skin lesions of infected living or dead persons or animals, as well as objects that may have become contaminated with infectious fluids, such as soiled clothing or linens (e.g. bedding or towels) used by an infected person.
• Avoid contact with wild animals, and consumption of bush meat.
• Returning travellers from areas affected by monkeypox should seek immediate medical attention if they develop any disease symptoms (e.g. sudden onset of high fever, swollen lymph nodes and rash) within three weeks of their return. They should inform their doctor of their recent travel history.

Monkeypox virus was first described in 1959 as a result of an outbreak among monkeys that had come from Singapore.

“Monkeypox virus was first discovered during a nonfatal outbreak at an animal facility in Copenhagen, Denmark, in 1958. The facility received a continual supply of Asian monkeys (mostly M. fascicularis) and rhesus macaques (Macaca mulatta), which were used for polio vaccine research. The first outbreak occurred 2 months after the monkeys had been received and the second outbreak occurred 4 months after the initial outbreak. The outbreaks occurred in M. fascicularis that had arrived from Singapore. The second outbreak occurred in another shipment of animals from Singapore.”

Review of experimental and natural infections of animals with monkeypox virus between 1958 and 2012