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Monkeypox is a rare disease caused by infection with the monkeypox virus. The virus is related to but different from the ones that cause smallpox and cowpox.

Monkeypox occurs mostly in west and central Africa.  However, some cases have been reported in the UK, Europe and other countries. Since May 2022 there has been an outbreak of monkeypox affecting the UK and other countries.

The risk of catching monkeypox is currently low in Wales.

More Information can be found below:

More information about the disease and signs and symptoms can be found below:

NHS 111 Wales - Health A-Z: Monkeypox

As monkeypox is caused by a virus similar to the one that causes smallpox, vaccines designed for smallpox are effective in preventing infection and may reduce the severity of monkeypox in those who have been exposed to someone with the infection.



Monkeypox FAQ's


About the vaccine

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 provide protection against monkeypox.

The current vaccine does not contain the smallpox virus. It cannot spread or cause smallpox.

The Smallpox vaccine available is a Modified Vaccinia Ankara – Bavarian Nordic (MVA-BN). It is currently distributed under 2 brand names, although it is the same vaccine.

The brand names are:

  • Imvanex
    Approved by the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK.
  • Jynneos
    The US labelled equivalent of Imvanex.

The MVA-BN vaccine has been used in the UK in response to the current and previous incidents.

You can be given this vaccine whether or not you have received a smallpox vaccination in the past.

The vaccine will be injected into the skin, preferably into the upper arm, by your doctor or a nurse.

After 2 doses of vaccine, most people develop antibodies and should therefore have a good level of protection against monkeypox. It is less clear what level of protection you get from a single dose given after contact with a case of monkeypox.

The vaccine has a very good safety profile. Like all vaccines it can cause side effects, but most of these are mild and short-lived and not everyone gets them.  

Side effects may be more common in people who have previously received a dose of live smallpox vaccine.

Side effects of the vaccine

Like most vaccines, the vaccine can sometimes cause mild side effects, including:

  • headache
  • chills, fever
  • aching muscles
  • pain in the joints or extremities
  • feeling sick, or loss of appetite
  • tiredness
  • pain, redness, swelling, hardness or itching at the injection site

Other reactions are rare. For more information on the vaccine including common and rare side effects, see patient information leaflet.

If your symptoms get worse or if you are concerned, call NHS 111 Wales on 111 or your GP surgery. Calls to NHS 111 Wales are free from landlines and mobile phones.

You can report suspected side effects of vaccines and medicines through the Yellow Card scheme. You can do this online at or by calling the Yellow Card scheme hotline on 0800 731 6789 (Monday to Friday, 9am to 5pm).


Public information resources

If you would like to learn more about the vaccine or the disease it protects against, a few information resources are available to help. You can also call NHS 111 or your GP practice for advice if you have any questions.