A British Airways crew has been put in isolation after one of them is understood to have caught monkeypox.
Two pilots and nine stewards and stewardesses have all been placed in quarantine for 21 days in Singapore, it has been reported.
The flight is understood to be on British Airways' London to Sydney route, which goes via Singapore, and it's thought the positive test came when the crew were returning to the UK.
Health officials reportedly detected the infection in a steward once staff were tested after landing on Sunday evening.
It comes as 793 cases of monkeypox cases have now been confirmed in the UK.
Authorities on Tuesday disclosed the case, saying the 42-year-old man had flown in and out of the city state in mid-June.
The infection is the first recorded case of monkeypox in South-East Asia linked to the recent global outbreak.
A total of more than 2,100 cases have thus far been detected across 42 countries since May.
According to the World Health Organization (WHO) over 80 per cent of cases have been found in Europe, but the disease has also spread to North America, South America and Australia.
The WHO has recorded one death in this outbreak.
A British Airways insider told the MailOnline : "One of them had it, so they impounded the whole crew. Now they have got to spend 21 days in quarantine.
"Everyone has been told not to talk about it – but it's all everyone is talking about."
A BA spokesperson told The Mirror: "We’re working closely with the Singapore Health Authorities and have offered assistance with any information they require.
"We’re in contact with our crew and providing the necessary support."
They added that the safety and security of its customers and crew is always its top priority and the risk to others on board is very low.
Meanwhile, some gay and bisexual men at higher risk of exposure to monkeypox should be offered the smallpox vaccine Imvanex, the UK Health Security Agency (UKHSA) has said.
Smallpox is in the same virus “family” as monkeypox.
There is currently no vaccine licensed in the UK or Europe for immunisation against monkeypox.
As monkeypox is related to the virus which causes smallpox, vaccines developed for smallpox are considered to provide “cross-protection” against monkeypox.
The UKHSA said the smallpox vaccine “is shown to be effective against monkeypox" but shouldn't be offered out to everyone.
It will only be offered to certain gay and bisexual men.
Eligibility criteria is likely to depend on a person’s sexual activity.
The UKHSA guidance states that a medic may advise vaccination for someone who “has multiple partners, participates in group sex or attends ‘sex on premises’ venues”.
Between May 6 and June 20, 793 cases of monkeypox have been confirmed in the UK.
Of these, 18 were in Scotland, three were in Northern Ireland, six were in Wales and 766 were in England.
Just five cases have been confirmed among women.
The majority of cases are among people in London - but cases have been found in other regions too.
Symptoms include new and unusual spots, ulcers or blisters anywhere on the body, fever, headaches, muscle aches, chills, fatigue and swollen glands.
Most people have a mild illness, with recovery within three weeks.
But in some cases, severe illness can occur and sometimes results in death.
The virus is not currently defined as a sexually transmitted infection, but it can be passed on by close and intimate contact that occurs during sex.
Spread of monkeypox can occur when a person comes into close contact with an infected animal or an infected human.
It may also occur when a person comes into close contact with material contaminated with the virus such as bedding.
Anyone can get monkeypox but the latest cases have been mainly linked to “sexual networks of gay, bisexual and other men who have sex with men”, the UKHSA said.
