Royal College of Nursing lead for infection and prevention control Rose Gallagher explains key details about the monkeypox outbreak
What is monkeypox and what is the background for the current outbreak?
Monkeypox is caused by a virus belonging to the Orthopoxvirus genus of the virus family Poxviridae, which famously includes smallpox, and also cowpox and Molluscum contagium, a common wart like disease. (Although sharing the ‘pox’ name, Chickenpox is caused by a different, herpes virus.)
Monkeypox is associated with animals (rodents and some vertebrates such as monkeys) as its main host. The infection was first identified in 1958 in monkeys in Central and West Africa. Spread to humans has occurred since, and it is endemic in human populations in nine African countries. However, up to now it has remained a rare infection outside Africa.
The current outbreak is affecting 27 countries. At the time of writing there are now 574 confirmed cases of infection in the UK. Most confirmed cases associated with travel history have reported travel to North America or Europe, rather than Africa, indicating the infection is being spread mainly through community transmission in countries where the disease is not endemic.
How serious is the infection?
There are two strains (or ‘clades’) of the virus: a West African clade that is milder, with associated mortality of around 1%; and a Congo Basin clade that is more severe, with associated mortality of approximately 10%.
The milder, West African clade has so far been identified in cases in the current outbreak and no one has died yet outside Africa. Most of those infected will recover within a few weeks without treatment.
Nonetheless, The World Health Organisation (WHO) has warned of the increased risk posed to vulnerable people including pregnant women and children, and that there is a danger of the disease becoming established in non-endemic countries.
A such, public health bodies are working to isolate cases and prevent wider spread of the virus, which is now officially an identifiable disease in the UK. It is therefore vital for all healthcare professionals to be vigilant and implement necessary infection prevention and control (IPC) measures, and help to ensure potential cases and contacts follow self-isolation advice.
How is the virus spread between people?
Monkeypox spreads primarily through direct contact with an infected person or animal (live or dead).
Person to person spread can occur if someone is in direct contact with an infected person’s skin lesions (pox) or their scabs, bedlinen or clothing. If someone with monkeypox also has respiratory symptoms, such as sneezing or coughing, then transmission may occur this way.
For nurses, the greatest risks are through handling bed linen or clothing of an infected person or if in direct contact with their lesions, scabs or respiratory droplets. Risks may be lower in non-hospital settings, and use of PPE should be informed by employer’s risk assessments if a person presents with suspected monkeypox. Be mindful that a person remains infective until all lesions have dried and scabs have fallen off.
Up until this outbreak it was considered very low risk to pass infection from one person to another, unless through prolonged direct skin to skin contact. Most cases so far have been associated with men who have sex with men. This includes bisexual men and their partners who would share close physical contact. It is important that these communities are supported with awareness of symptoms or infection presentation, so they can seek help if needed and prevent onward infection to both men and women, whether partners or household contacts.
What are the main signs and symptoms of infection?
The incubation period (the length of time between contact with an infected person and first symptoms appearing) is between 5 and 21 days.
Typical symptoms have been reported as fever, headache, muscle and back ache, swollen lymph nodes, chills and tiredness. A rash may appear 1-5 days after onset of fever with lesions progressing through various stages until scab development and falling off, as with chickenpox. It is important to note that lesions of different appearances and stages may be seen at the same point in time.
The UK Health Security Agency (UKHSA) provides definitions of possible and probable cases here and further information on clinical features, including examples of lesions at different stages, here.
How should nurses in primary care deal with a suspected case?
The UKHSA advice is to discuss any potential case with local infection specialists, who may then contact the Imported Fever Service (IFS) to refer the patient to an appropriate hospital for further assessment.
If you see a person who has been identified as a contact of a confirmed case, get in touch with your local health protection team for advice.
Any nurse coming into direct contact with a case should follow their employer’s policies on the management of people with monkeypox. Any concerns or questions should be shared immediately with your local IPC advisers or consultant microbiologist on call. The IFS also provides support, with 24-hour access to telephone support and advice.
What PPE should nurses use if in direct contact with a potential case?
Nurses should refer to the UKHSA, Public Health Scotland, Public Health Wales and Public Health Agency Northern Ireland consensus statement, and local policies. NHS England also recently issued information on monkeypox, including the advice to follow the National IPC Manual England for confirmed cases.
Note that with possible and probable cases of monkeypox, the consensus statement advice is for healthcare workers to wear a surgical face mask, or FFP3 mask and eye protection if the patient has symptoms of a lower respiratory tract infection. Gloves and an apron should also be worn, and eye protection if there is a risk of eye splash, for example from doing diagnostic tests.
How are cases being managed?
Most cases presenting at the moment appear to be mild and the illness is viewed as self-limiting. Treatment is mostly supportive, with those infected recovering in 2-4 weeks.
Crucially, patients with possible, probable or confirmed monkeypox are advised to avoid close contact with others until all lesions have healed, and scabs dried off. This means they should stay at home and self-isolate, unless requiring medical care or other urgent health or wellbeing issues. Latest advice stresses that they should also avoid contact with other household members, including sleeping and eating in a different room and using a separate bathroom, where possible. The effects of isolation may be hard for some patients to experience.
How are contacts being managed? Why is Smallpox vaccine being given to contacts?
The UKHSA is tracing contacts of monkeypox cases to advise them to isolate. Those that are closest contacts and therefore deemed high risk are required to self-isolate for 21 days from exposure. They should avoid contact with the immunosuppressed, pregnant women and children aged under 12 where possible.
In addition, some contacts are being offered post-exposure prophylactic treatment with the Smallpox vaccine, to help prevent spread of the infection. This includes, for example, healthcare staff who may have examined a patient before diagnosis without appropriate PPE, or who have had direct contact with a confirmed case even while wearing PPE.
The Smallpox vaccine is expected to provide some cross-protection – previous data suggest it may be up to 85% effective in preventing monkeypox infection.
Full details of the UKHSA classification of contacts and their appropriate follow-up and treatment is available here and information on the use of pre- and post-exposure Smallpox vaccination here.
What other measures are being taken to prevent transmission?
The UK Health Security Agency has also announced a strategy for pre-exposure vaccination with the Smallpox vaccine. This involves targeted vaccination of gay, bisexual and other men who have sex with men who are at high risk due to a large number of contacts. Men eligible for the vaccination will be identified by sexual health services based on markers for high-risk behaviour similar to those used to identify men for HIV pre-exposure prophylaxis.
More information will become available as the outbreak progresses, so information and advice may change.
This article was updated on 24 June 2022 to include new information about the pre-exposure vaccination strategy in high-risk individuals.
Further reading and resources
UK Government. Monkeypox: guidance
Monkeypox Resources | British Association for Sexual Health and HIV (bashh.org)
Principles for monkeypox control in the UK: 4 nations consensus statement – GOV.UK (www.gov.uk)
NHS Central Alerting Service: Immediate actions in response to cases of Monkeypox Virus in the UK with no known travel history CAS-ViewAlert (mhra.gov.uk)
World Health Organization. Monkeypox outbreak 2022 – Global (who.int)