There are approximately 16 million approved vaccine doses available for use against monkeypox and other candidates are being considered, according to the World Health Organization (WHO).
Most of the vaccines are stored in bulk, which means it will take several months to get them into vials, WHO Director-General Dr. Tedros Adhanom Ghebreyesus said Wednesday.
Bavarian Nordic’s Imvamune or MVA-BN vaccine, normally used to treat smallpox, has been approved by Canada, the United States and the European Union.
Two other vaccines – LC16 and ACAM-2000 – are also being considered, said the WHO chief, urging countries with stockpiles to share doses while supply is limited.
“We still lack data on the effectiveness of vaccines for monkeypox or how many doses might be needed,” Tedros told reporters during a virtual news conference on Wednesday.
Monkeypox was declared a global health emergency by the WHO on Saturday.
Globally, more than 18,000 cases of monkeypox have been reported in 78 countries, with at least 70 per cent in Europe. Around 10 per cent of patients have been hospitalized in the current outbreak and five have died, all of them in Africa, the WHO said.
Canada has confirmed 745 monkeypox cases as of July 26, but those numbers are expected to rise, according to the Public Health Agency of Canada.
However, at this time, the UN health agency is not recommending mass vaccination, Tedros said. It is only recommending vaccination for high-risk groups, including health-care workers and men who have sex with men with multiple sexual partners.
The WHO estimates that between five million and 10 million doses of vaccine will be needed to protect all high-risk groups.
Imvamune is a two-dose vaccine. WHO experts cautioned that it takes several weeks after getting the second dose of the vaccine to be fully protected, so people should take other precautions until that point.
They also called for more research into the effectiveness of the shots against monkeypox.
“At the moment, we don’t have the data to confidently say that the vaccine is the best approach to this,” said Dr. Soumya Swamintham, WHO chief scientist.
In Canada, the National Advisory Committee on Immunization (NACI) came out with new guidelines last month saying anyone with a high risk of exposure to a probable or confirmed case of monkeypox, or someone who has visited a setting where transmission of the virus is happening, should receive one dose of the Imvamune vaccine.
The vaccines are being offered to people who have been exposed to monkeypox as well as at-risk groups. Appointments can be made online or by phone through the public health units.
To date, the government of Canada has deployed more than 70,000 doses of Imvamune to provinces and territories.
The CEO of Danish company Bavarian Nordic said it is in talks to potentially expand production capacity for its vaccine.
Bavarian has annual production capacity of 30 million doses, including the smallpox vaccine and other vaccines it makes.
— with files from Reuters