“As of now, given the self-limiting nature of the disease, MOH does not recommend the mass vaccination of the whole population against monkeypox, because the benefits do not outweigh the risk,” Mr Ong said in a Facebook post.
“We will continue to monitor the situation closely.”
In Singapore, four imported and four local cases of monkeypox have been detected.
“There was no evidence of them transmitting the infection to other people in the community,” he said.
“MOH also quarantines their close contacts for up to 21 days since last exposure, while lower risk contacts are monitored through phone surveillance.”
One of them is an imported case involving a 46-year-old Estonian man who came to Singapore from London on Jul 21 and sought medical care on Jul 23 after developing symptoms.
The other is a 26-year-old Singaporean man who developed rashes and sought medical attention on Jul 24.
A public health emergency of international concern is the top alert available to the WHO to tackle a global disease outbreak.
It is defined as “an extraordinary event which is determined to constitute a public health risk to other states through the international spread of disease and to potentially require a coordinated international response”.
According to the United States Centers for Disease Control and Prevention (CDC), smallpox vaccines can protect people from getting monkeypox because the viruses that cause the diseases are closely related.
The Jynneos and ACAM2000 smallpox vaccines are currently being used in the US, and while past data has shown smallpox vaccines to be up to 85 per cent effective against monkeypox, they can have serious side effects.
The US Food and Drug Administration (FDA) said ACAM2000 can cause myocarditis and pericarditis. Those who have recently received the vaccine can also infect unvaccinated people with the vaccine virus if they have close contact.