Mpox vaccine to be offered to healthcare workers at highest risk and close contacts of confirmed cases

SINGAPORE: Singapore will offer the mpox vaccine to healthcare workers who are at the highest risk of exposure to the disease, as well as close contacts of confirmed cases.
There is no need for mask-wearing measures for people who are well, based on current evidence on how mpox is spread.
These were announced at a press conference on Wednesday (Sep 4) against the backdrop of growing concern about the clade 1 strain, which prompted the World Health Organization to declare a global mpox public health emergency for the second time in two years. 
“We do not have full information on the characteristics of this virus, but we have good information on how it behaves, the key characteristics, which allow us to develop a response plan,” Health Minister Ong Ye Kung said. 
Singapore’s measures may have to adapt over time, he added, as the situation evolves and as the world understands the virus better.
Clade 1 is the deadlier subtype of mpox.
A mutated strain of clade 1 – clade 1b – emerged in September 2023 and was first detected among sex workers in the Democratic Republic of Congo. It has driven the recent surge in cases in African countries.
Singapore has not detected any clade 1 cases in the country to date.
All 14 mpox cases in Singapore so far this year have all been of the less severe clade 2 subtype.
“I would say the bottom line is this: I think we were right to be worried about mpox clade 1,” said Mr Ong.
“But we think this is likely to be a troublesome virus that we can manage. It will very unlikely lead to the kind of disruption that happened during COVID-19.” 
JYNNEOS, the live, non-replicating vaccine, has been used in Singapore for protection against mpox and smallpox, and will be offered for free to two groups of people.  
Healthcare workers who are at the highest risk of exposure to mpox, such as those working at the National Centre for Infectious Diseases (NCID), can receive the vaccination for additional protection, on top of personal protective equipment and infection control protocols. 
As for close contacts of confirmed mpox cases, the Expert Committee on Immunisation has recommended a single dose of the vaccine within 14 days of exposure – this will be administered while they are in quarantine. 
The quarantine period is currently set at 21 days, which is the incubation period observed in Africa, said MOH in a separate press release. 
Singapore’s current supply of the JYNNEOS vaccine is projected to be sufficient for the current strategy, the ministry said, adding that there is “good evidence” that indicates that smallpox vaccination gives “cross-protection” against mpox.
Given that smallpox vaccination was required in Singapore until early 1981, there will be some mpox immunity among a “significant” segment of Singapore, or those who are 45 years old and above, the ministry added.
Out of 100 infected cases in the Democratic Republic of the Congo, about three to four die, which is quite a high and worrying number, said Mr Ong, adding that the majority of them are young people below 15. 
The actual statistics for developed countries like Singapore are likely to be lower, he added. 
Singapore needs to pay attention to more vulnerable groups like older people who are immunocompromised, as well as children, said the Health Minister. 
“We should not resort to draconian and very disruptive measures like what we did during COVID-19. No countries are doing that now,” he added. 
“The best way is to suppress the spread of the virus, provide proper treatment to those who are infected, and have a very effective vaccine strategy.” 
Although the mpox clade 1 virus appears to be more infectious, it is “far less transmissible” compared to respiratory viruses such as influenza or COVID-19. 
Based on the current understanding of the virus, population-wide mpox vaccination is not recommended for now, MOH said in the press release. 
It added that mask-wearing is not recommended for people who are well, based on current evidence that mpox is spread mainly through close physical contact.
If there is evidence of significant respiratory transmission, such as outside of households and in public areas, the health ministry will consider implementing wearing masks on public transport and in crowded indoor places.
Close physical contact includes sexual contact, mouth-to-mouth, skin-to-mouth, or skin-to-skin contact, said Mr Ong. 
“What makes clade 1 different from clade 2 is that the global outbreak of clade 2 is mostly among men who have sexual relationships with men, within those circuits,” he added. 
However, clade 1 in the Democratic Republic of Congo does not spread primarily through “just sexual networks”, but also through family members living in the same household where there is some close and physical contact, said Mr Ong. 
In preschools and schools, existing measures for other infectious diseases remain relevant, said MOH, noting that students will be visually screened for symptoms. 
With the Ministry of Manpower and the National Environment Agency, MOH is conducting wastewater testing at migrant worker dormitories and the Onboard Centre. 
Newly arrived work permit holders also go through temperature and visual screening, said MOH in the press release. 
All suspected adult and paediatric clade 1 cases identified by primary care providers will be taken to NCID and KK Women’s and Children’s Hospital respectively. Families with both adults and children will be conveyed to the National University Hospital, said MOH. 
Cases who test positive for clade 1 will continue to be isolated in healthcare facilities until they are no longer infectious to prevent further exposure to the community, the press release read. 
Once a clade 1 case is confirmed, MOH will immediately start contact tracing. Close contacts will be quarantined in a designated government facility. 
Since Aug 23, Singapore started conducting temperature and visual screening at air and sea checkpoints for travellers and crew arriving from places that may be exposed to the risk of mpox outbreaks. 
All travellers must report mpox-related symptoms like fever or rash, as well as their travel history, through the SG Arrival Card, MOH said at the time. 
While mpox has been known for decades, a new deadlier and more transmissible strain – known as clade 1b – has driven the recent surge in cases.
According to the World Health Organization (WHO), clade 1b causes death in about 3.6 per cent of cases, with children more at risk.
In August, WHO declared mpox a global public health emergency for the second time in two years, following an outbreak in the Democratic Republic of Congo that spread to neighbouring countries. 
On Aug 22, Thailand confirmed Asia’s first known case of the new, deadlier clade 1b strain.
The 66-year-old European man landed in Bangkok from Africa on Aug 14 and was sent to hospital with mpox symptoms.