The US Food and Drug Administration (FDA) authorized the intradermal injection of monkeypox vaccines in adults, in an attempt to manage low vaccine supply versus rising demand for vaccines, on Tuesday, 10 August.
Intradermal injections are administered between the layers of skin rather than under the skin, and are expected to cut vaccine requirements to 1/5th of the present need.
While no dedicated vaccine exists currently for monkeypox, repurposed smallpox vaccines have been approved for use in many countries including the US, Australia, the UK, the European Union, and Singapore.
The World Health Organization (WHO) declared monkeypox a Public Health Emergency of International Concern (PHEIC) on 23 July, and soon after the US declared the virus a national health emergency.
At present, the US has granted emergency use authorization of the use of the of Bavarian Nordic's Jynneos smallpox vaccine, which was approved for treament of both smallpox and monkeypox, in 2019.
The FDA authorized emergency use of Jynneos to prevent severe disease from monkeypox, via an order dated 9 August.
"This action paves the way for the federal government to get up to five times the amount of doses administered out of a single vial of the JYNNEOS vaccine."White House Press Briefing
While the Jynneos smallpox vaccine's original approved route of administration is subdermal, the intradermal injections are expected to be effective to combat monkeypox in both adults and children.
The FDA has also approved the administration of Jynneos to those under the age of 18 if they fall into high risk groups like those with autoimmune diseases.
Intradermal injections require a different needle from subdermal injections, more akin to needles used for allergy or tuberculin skin tests.
The US administration has said that they have over 440,000 doses of the smallpox vaccine, allowing them to vaccinate approximately 2.2 million people with the present stock of vaccines.
Meanwhile, if you have any doubts about monkeypox vaccines, check out our FAQ which answers the questions you may have.
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