Mpox, (previously known as monkeypox), is a serious infectious disease that can present itself in the form of painful skin lesions, these can appear on any part of the body.

Mpox is a rare infection most commonly found in central and east Africa. The infection can be caught from:

• any close physical contact with mpox blisters or scabs (including during sexual contact, kissing, cuddling or holding hands)
• touching clothing, bedding or towels used by someone with mpox
• contact with bodily fluids such as saliva, snot or mucous.

Mpox is usually mild and can get better within a few weeks without treatment. But if your symptoms are more severe and you become unwell, you will need treatment in hospital.

The mpox (MVA) vaccination

You are being offered a vaccination to help protect you against mpox. MVA vaccine helps prevent or reduce the severity of mpox (and smallpox) infection.

If you are HIV positive or have any other condition or treatment leading to a weakened immune system, the vaccine may not protect you as well. Let your doctor or nurse know.

The vaccine is manufactured in Europe by Bavarian Nordic1. When you are given the vaccine, your immune system (the body’s natural defence system) produces antibodies against the mpox virus.

The MVA vaccine does not contain smallpox or mpox virus and cannot spread or cause smallpox or mpox.

Imvanex vaccine has been authorised by the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) to protect against smallpox and mpox.

The UK Health Security Agency (UKHSA) and the Joint Committee on Vaccination and Immunisation (JCVI) recommends the use of MVA vaccine as part of the response to cases of mpox.

Who MVA is recommended for

UKHSA currently recommends that MVA is offered to:

• healthcare workers who are caring for and who are due to start caring for a patient with confirmed monkeypox
• bay, bisexual and other men who have sex with men. Your clinician will advise vaccination for you if you have multiple partners, participate in group sex or attend ‘sex on premises’ venues
• people who have already had close contact with a patient with confirmed monkeypox. Vaccination with a single dose of vaccine should be offered as soon as possible (ideally within 4 days but sometimes up to 14 days)
• people who are members of a group or attend a setting where there is a case or cluster, or where some of the members have had close contact with a case

Does the vaccine work?

2 doses of vaccine have been shown to give a high level of protection against mpox. Protection is also very good after the first dose, but a second dose is sometimes advised for long term protection.

The vaccine may not completely prevent infection but even if you catch mpox, the symptoms should not be as bad.

The first dose prepares your immune system so it can respond much more quickly if you come into contact with mpox. The vaccine also takes time to work. It might start to work after a few days and should reach the highest protection by about 4 weeks.

The second dose can be given after 28 days but can be given much later, even after a few months. A longer time between the first and second doses should improve your long term protection.

Even after 2 doses you should continue to be aware of the risks and symptoms of mpox. If you develop symptoms, stay at home and call 111 or a sexual health clinic.

Side effects of MVA vaccine

The vaccine has a very good safety profile. Like all medicines and vaccines it can cause side effects, but most of these are mild and short-lived and not everyone gets them. Unlike the old smallpox vaccine, vaccination does not leave a scar.

Side effects may be more common in people who have previously received a dose of live smallpox vaccine. These people only need a single dose of MVA to boost their existing protection.

You should tell the doctor or nurse if you have received smallpox vaccination in the past or if you have atopic dermatitis, as the risk of side effects from the MVA vaccine may be higher.

Common side effects

Common side effects include pain and itching at the injection site and headache, muscle ache, sickness and tiredness. About 1 in 10 people will have chills and fever, but these should not last more than a few days.

If you experience any of the side effects listed above, you should rest and you can take the correct dose of paracetamol to help relieve the symptoms.

If you already have atopic dermatitis (a form of eczema), you may experience more intense local skin reactions (such as redness, swelling and itching) and other general symptoms (such as headache, muscle pain, feeling sick or tired), as well as a flare-up or worsening of your skin condition.

Serious side effects

Some other conditions have been more rarely reported in people who received the vaccine. In the spirit of openness, the vaccine product insert mentions all these conditions – even those reported from single cases – but this does not mean that the vaccine was responsible. If you get any side effects, talk to your doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet.

By reporting side effects you can help provide more information on the safety of this vaccine.

If you have the following symptoms shortly after vaccination, ring 999 (or ask someone to do this for you):

• difficult or noisy breathing or wheezing
• swollen tongue
• prolonged fainting or unconsciousness
• confusion

These symptoms may be a sign of a rare but serious allergic reaction and typically happen within 15 minutes of vaccination. Simple faints are much more common after vaccination. If you do faint, stay flat on your back with your legs raised. If this doesn’t make you feel better, then call for help.

For other symptoms, contact 111 or your health professional.

Reporting side effects

Please report any suspected side effects:

• online at Yellow Card Scheme
• downloading and using the Yellow Card app:
  • Apple
  • Android
• calling the Yellow Card scheme on 0800 731 6789 (9am to 5pm)

By reporting side effects you can help provide more information on the safety of this vaccine.

Those who should not receive MVA vaccine

The only people who cannot receive the vaccine are those who suffered a sudden life-threatening allergic reaction to a previous dose of the vaccine, or any ingredient of vaccine before. The vaccine contains trace amounts of chicken protein, benzonase and gentamicin and ciprofloxacin (antibiotics).

Delaying mpox vaccination

If you are ill with a high temperature you may need to be assessed to determine if you are displaying early signs of mpox. If your illness is not related to mpox, you may still be offered the vaccine. The presence of a minor infection, such as a cold, should not require postponement of the vaccination, but talk to your doctor or nurse first.

Taking other medications and having the MVA vaccine

Tell your doctor or nurse if you are taking or have recently taken any other medicines or if you have recently received any other vaccine. In most cases, you should be fine to have the vaccine. The vaccine can be safely given to people who are living with HIV infection, those who are taking PreP and at the same time as other important vaccines including those against HPV and hepatitis A and hepatitis B viruses.

How is MVA given

There are two methods used to give the MVA injection, preferably into the upper arm. One method injects below the skin or into the muscle (similar to most other vaccines), the other one injects into the skin, like the BCG vaccine against TB. Both methods are highly effective.

Driving and using machines

There is no reason to believe that the vaccine would affect your ability to drive or use machines. Fainting after vaccination is quite common, so you should wait for 15 minutes after the jab before you drive.

Further information

The vaccine is available in specialist sexual health services

For more information about mpox and where to find a vaccination site visit the NHS website.

You will get more information on this medicine from the package insert that the doctor or nurse should give you. The insert is also available on the European Medicines Agency website.