Monkeypox was first discovered in 1958 on a monkey by a Danish virologist. It is a human orthopoxvirus and a viral zoonotic disease. The first human case detected was in 1970 and has mostly been associated with cases in the Democratic Republic of Congo and other parts of central and west Africa. The main animal reservoir is within rodents.
Monkeypox has a very low mortality rate. The first case in the US was detected in 2003 from imported rodents. The first UK cases were detected in 2018 and the concern with this latest outbreak is that cases are currently being identified found in countries that have never previously affected.
The smallpox vaccine provides protection against monkeypox.
Transmission
The virus is not easily transmittable, which is reassuring. Monkeypox can spread via animal to human contact and human to human contact. Spread from animal to human can be via a bite or direct contact. Spread from human to human can be via droplet spread or infected fluids crossing mucosal membranes or direct contact with infected fluids e.g saliva, genital fluids etc.
Other possible infectious routes can be:
- Via direct contact with the blisters of a patient with monkeypox.
- Via clothes or bed linen of an infected patient.
There are no known cases currently within animals in the UK, although there has been some recent concern about the theoretical potential for household pets to become infected. Latest guidance suggests that people should try and avoid contact with their pets, its bedding and litter for 21 days if they contract monkeypox.
Clinical features
The virus has an incubation period of 5-21 days, hence the need to isolate for three weeks following a confirmed contact. Those identified as high risk following contact with a confirmed case are also being asked to isolate for 21 days.
It is often a self-limiting illness with most patients recovering fully.
The main symptoms to look out for include a temperature, severe headache, arthralgia, myalgia, lymphadenopathy and fatigue.
The difficulty is that the above symptoms are vague and extremely common symptoms for us to see within general practice with a broad differential.
After the fever, within day 1-5 a rash normally appears and goes through a series of changes that which may allow you to make a diagnosis more easily if the rash is seen at one of the stages described below:
- Early vesicle
- Small pustule
- Umbilicated pustule
- Ulcerated lesion
- Crusted lesion
- Scabbed lesion
The rash can be mistaken for chickenpox so a careful history is important particularly taking into consideration risk factors for developing the condition such as:
- Recent travel to Africa.
- Recent contact with someone who has monkeypox.
- Sexual contact with another gay or bisexual man.
The UK Health Security Agency’s case definition for monkeypox is here.
Key features in the history
- Symptoms as above
- If a rash is present, then a detailed enquiry about the rash to exclude other causes of rash.
- Recent travel and if so where?
- Any known contacts
- Any known immunosuppression
- Is the patient pregnant?
Practical tips for GPs
- If a patient is requesting an appointment for a new rash, it may be worth considering as a practice whether you wish to assess this remotely first via a picture before asking the patient to visit the surgery.
- You may even wish to consider risk assessing patients with the other recognised symptoms depending on whether you are in an area of high prevalence of this condition.
- Remember to keep your diagnostic net cast wide for returning travellers with fever – other conditions remain more likely eg malaria.
- Opportunisitic safe sex advice may also be appropriate alongside screening for STIs once the acute problem has been managed safely.
Complications
These include:
- Bronchopneumonia
- Encephalitis
- Loss of vision via corneal infection.
Complications are rare and mortality remains low. Immunosuppressed groups and children are more susceptible to complications.
What to do in the event of a suspected case
If you suspect a case via remote assessment then discuss with your local infectious diseases team which will advise you on the next steps accordingly.
As of 8 June 2022 monkeypox is a notifiable disease which means all doctors in England are required to notify their local council or health protection team if they suspect a patient has the virus.
If it transpires that a patient you are consulting face to face may have this condition, then ensure to isolate them if able and don appropriate PPE as you may have done for the early stages of the COVID-19 pandemic.
Again, call your local infectious diseases team who can advise you on what tests may be needed or whether direct referral for further assessment and testing maybe needed.
If you then need to clean and decontaminate the room after the consultation discuss the necessary steps with your local health protection team. It is advised that the room is not used until this discussion and a plan for decontaminating is in place.
You will need to also take advice from them on any staff isolations that may well be needed. Latest guidance (the principles for monkeypox control guidance listed below) says that where possible, pregnant healthcare workers and severely immunosuppressed individuals should not assess or clinically care for individuals with suspected or confirmed monkeypox.
Treatment
Treatment for monkeypox is mainly supportive and possibly managing secondary complications, for example bacterial infections that may require antibiotics. This is going to be largely secondary care driven. Ophthalmology teams maybe involved if vision is affected.
Antivirals such as cidofovir and tecovirimat may also be used in some circumstances. The smallpox vaccine may also be used to control outbreaks.
Contact tracing
Contacts of monkeypox cases are risk assessed and grouped into low, medium or high. Depending on what group these contacts are placed will then determine how they are managed.
It is recommended that those identified as medium or high risk are offered post-exposure prophylaxis, which involves receiving the smallpox vaccine Imvanex. This should ideally happen within four days of exposure, but can be given up to 14 days after exposure.
- Dr Singh is a GP in Northumberland
Useful link
- Principles for monkeypox control in the UK: 4 nations consensus statement
- Letter from NHS England outlining current response to the outbreak and guidance on management of cases
- Latest information from the UK Health Security Agency on the current outbreak
This article was amended on 9 June to include details of monkeypox becoming a notifiable disease and to add details of the NHS England letter and guidance above.
