Britain could be left without monkeypox vaccines in the coming weeks as the UK awaits a bumper shipment of 100,000 doses next month.
Health officials have already received more than 50,000 doses but demand for the vaccine has outstripped supply. Reports claim the remaining number of doses could be just 8,000.
The monkeypox vaccine, called Imvanex, is administered as an injection and a person needs two doses which should normally be four weeks apart, for full protection.
Britain ordered 100,000 more doses of Imvanex in July which are due to be delivered in September by Bavarian Nordic, the Danish pharmaceutical firm which is the only place in the world making monkeypox jabs.
The vaccine also protects against smallpox, which was eradicated in 1980, so before the current outbreak countries only had small stockpiles in case of a bioterrorism attack or a rare, localised case of monkeypox brought from overseas where the virus is endemic, such as in western Africa.
But with around 3,000 cases of the virus now in the UK alone — with the overwhelming majority in gay men as it is spread predominantly via sexual networks — there has been a huge surge in demand in the UK.
This has also been mirrored globally, with the one company rapidly trying to scale up production to meet the demands of the outbreak, which the World Health Organization (WHO) has labelled as a Public Health Emergency of International Concern (PHEIC).
Now, all gay men who are promiscuous, have recently had an STI, or engage in group sex are eligible to get the vaccine as a preventative measure, and are being encouraged to reach out to their local sexual health clinic to get inoculated.
The UKHSA last week said the outbreak in Britain appears to be slowing, largely as a result of getting as many at-risk men vaccinated as possible.
Protection from the vaccine is long-lasting, with people who got a smallpox jab in the UK before it was stopped in 1971 still protected now from monkeypox.
As a result of the robust and durable protection, public health bosses prioritised first doses in order to maximise how many people have some protection. The UKHSA approach means it is content to deplete their vaccine reserves as quickly as possible in order to build up maximum protection in the exposed community.
This rapid rollout approach will build up protection rapidly, but means there may be a period of time where the nation has no more available doses before the resupply shipment arrives.
The delivery schedule is dictated by Bavarian Nordic, not UKHSA, and experts believe the doses already given out have been effective at helping stymy the outbreak.
Vaccine 'could be up to 99 per cent effective'
Dr Mary Ramsay, the director of clinical programmes at UKHSA, said: “The roll out is continuing at pace, with the vaccine being offered to individuals at higher risk of coming into contact with monkeypox in order to offer them protection and to help contain the current outbreak.
“The remaining approximately 100,000 doses are expected to arrive in the UK in September. The thousands of vaccines administered by the NHS to date among those at highest risk of exposure should have a significant impact on the transmission of the virus.”
Dr Nick Phin, the director of public health science and medical director at Public Health Scotland, said the country wants to vaccinate around 6,000 people, and has so far only received 3,000 doses.
He added that he believes the vaccine could be up to 99 per cent effective.
“[People] mention 85 per cent, but I actually put it much higher, it is nearer 98-99 per cent,” he said.
“We do know that it's effective, it is highly effective. I have no concerns about the effectiveness of this vaccine, it’s got a good track record and the trials have consistently shown a high level of protection.”