Monkeypox: Q&A factsheet
2 July 2022. Related: News.
Simon Collins, HIV i-Base and Alex Sparrowhawk, UK-CAB
This Q&A is about the recent cases of monkeypox (MPX) in the UK. At some point this name may be changed.
This page will be updated as new information becomes available. Last update 2 July 2022.
Although monkeypox (MPX) is still very rare in the UK the risks are significantly higher for some gay and bisexual men.
The recent outbreak is significant and needs to be taken seriously.
The information below is organised into six sections.
- MPX basics
- Prevention and transmission
- Testing and treatment
- MPX and HIV
- Other questions
- References and more information
1. MPX: first questions
What is monkeypox?
Monkeypox is an infection caused by the monkeypox virus (MPV or MPxV).
MPX is usually rarely seen in the UK. However, since May 2022, more than 1075 cases of MPX have been reported in the UK. Nearly all cases are in gay and bisexual men.
By late June, MPX has also been reported in over 6100 people globally in other countries where MPX is not usually seen, including the UK cases above. International travel links cases across Europe and in the UK to Spain, Portugal, Canada, the US, Australia in over 35 new countries.
The risk of MPX needs to be taken seriously. This is both for your individual health and so that it doesn’t become an established infection.
The name monkeypox may be changed. This is because the current name is not accurate. Monkeys are rarely affected and the name leads to additional stigma.
Is MPX easy to catch?
Although MPX is still a very low risk for most of the population, the risk is significantly higher for gay and bisexual men.
With direct skin contact, MPX highly infectious.
See below for detailed information about risk and prevention.
Are there different strains of MPX?
Yes. Like most viruses there are different strains of the virus.
The two main strains are a mild form (linked to West Africa) and a more aggressive form (linked to Central Africa).
Luckily, the current cases all involve the mild version.
There is also a call for the WHO to rename these strains. Just as in COVID, it is not helpful to stigmatise a region with an illness.
What are the main symptoms?
Many of the early general symptoms are similar to other infections like colds, flu and COVID.
These include fever, headache, muscle aches, backache, swollen lymph nodes, chills and feeling very tired.
Sometimes they are mild. And some people do not get symptoms at all.
Skin spots, ulcers or blisters develop a few days after the symptoms above. This commonly starts as red skin bumps, often in the genitals or face. They can develop into blisters that can then break down into ulcers or sores. These develop a scab that eventually falls off.
The spots/ulcers can be in any part of the body. This can include in the mouth or in the genital area, including inside the anus.
Sores can be painful, aggressive and unpleasant. They can be itchy but it is important not to scratch. This could spread the virus to other parts of the body. If MPX infecting the eyes can be very serious.
The examples below show different stages of the ulcers. They can vary in size from a few millimetres to a centimetre in diameter.
How are the MPX ulcers different to other infections?
- Ulcers can be similar to several more common infections. These include chicken pox, syphilis, herpes, molluscum, cryptococcal infection, shingles (VZV) or even some heat rashes.
- MPX ulcers are usually deeper and harder than seen with other infections
- MPX ulcers can appear in crops every three to five days, and unlike chickenpox can take several days to evolve into blisters.
- MPX ulcers often have a dip in the centre with a dot in the middle. This is called umbilicated.
What do spots/ulcers look like?
A few examples of ulcers are included below. Please click the picture to open larger view.
Other pictures at this link to the US CDC.https://www.cdc.gov/poxvirus/monkeypox/clinicians/clinical-recognition.html
Genital lesions are included in this paper in the NEJM.
How serious is MPX?
Most cases are mild or moderate.
With support, most people will be able to self-isolate at home. In the current outbreaks, only 1 in 10 people (10%) need to be treated in hospital. This is usually to help manage any pain.
- Mild infections can be uncomplicated with less than 25 spots or ulcers.
- Moderate infections involve 25 – 100 spots or ulcers.
- Severe infection is defined as having more than 100 ulcers, or more severe reactions.
- Roughly 1 in 100 cases can include serious complications.
What complications can occur with MPX?
More severe infections can involve 100–250 spots or ulcers.
- This can lead to inflammation of the lungs (pneumonitis), brain (encephalitis), eyes (keratitis) and bacterial infections.
- Some of these risks are linked to touching an ulcer and then touching another part of your body. If sores become infected with bacteria, they need to be carefully treated. Otherwise this can lead to septicaemia (blood poisoning).
Serious infections need to be managed in hospital.
Is MPX an STI?
Currently, MPX is not defined as an STI. This is because even though the virus has been found in sexual fluids, infection is more likely to be through close physical contact.
So even though the virus has been detected in semen, this doesn’t make it an STI. However, further research is ongoing.
But saliva is likely to be infectious. This means that kissing and oral sex could be the risk that explains transmission in sexual networks.
MPX is transmitted via close contact whether or not this involves sex. This includes by close skin contact, or contact with infected clothes, towels and bed linen. Having sex involves close contact. Sexual contact is not necessary, but any spots or ulcers will be very infectious.
Even if later research finds MPX is infectious in sexual fluids, the larger risk is likely to come from close contact.
Condoms, for example, will not generally protect against MPX. However, one exception might be if MPX remains in sexual fluids after the infections is otherwise cleared. This has been seen with other infections, including Zika virus and Ebola.
Until there is more research, UK guidelines from 30 May recommend that people with confirmed MPV use condoms for eight weeks after the infection has cleared.
Does MPX just affect gay men?
No, viruses do not care about sexuality.
Recent infections in gay men is because this is one of the networks of an early infection.
2. Transmission and prevention
What is the risk of catching MPX?
So far the risk of catching MPX is generally very low. This is because MPV is still rare in the UK.
However, this risk is much higher for some people. It is much higher for gay and bisexual men who have multiple partners, or whose partners have these risks.
But knowing about the risk is important in settings where MPX risks are already higher.
- Casual social contact is generally very low risk in all settings.
- But this can be higher with sexual partners and people you live with.
For both reasons, people diagnosed with MPX need to self-isolate for 21 days, or until the infection is cleared.
How is MPX transmitted?
MPV can be spread in several ways.
- Through droplets in the air.
This usually involves spending extended time with someone in a room with poor ventilation. For example, spending more than 3 to 6 hours, where you are within two metres.
So casual contact in the same room is a very low risk, unless someone directly sneezes in your face.
But transmission by air is a much higher risk for people in the same household. This should involve taking special precautions to limit contact with people you live with.
- By close contact with someone who has symptoms.
This is especially after the ulcers have developed. This is because the fluid in MPX blisters will be highly infectious.
Skin contact with ulcers is a high risk of catching MPV.
- By sharing sheets and towels.
Sharing sheets and towels with someone with MPX can also be a route of transmission.
Washing sheets and towels can also be a risk. This is in case infectious material is shaken into the air.
A machine wash at a 60 degree cycle will be enough to sterilise sheets, clothes and towels.
Simple cleaning with regular cleaning products will be enough to sterilise surfaces, toilets and bathrooms. Diluted household bleach can be used but is not necessary.
However, MPX can remain infectious for more than 15 days on hard surfaces. This could be much longer in soft material such as bedding and clothing. This US CDC leaflet has more information, including on cleaning.
See references 12, 18 and 19.
How long after an exposure risk does MPX take to develop?
Based on the limited data, it can take from 1 to 3 weeks until MPX produces symptoms.
For most people this is 10 to 12 days after contact.
When is someone infectious?
The risk of onward transmission starts as soon as there are symptoms.
This is why it is important to call a doctor or clinic for advice. But please do not visit a doctor or clinic without calling first so this can be arranged properly. Otherwise health workers might also need to isolate.
The risk of transmission usually ends after the skin blisters and scabs have gone. However, even after MPX tests negative on swabs, blood and genital fluid can still test positive.
This is why the UK recommends using condoms for eight weeks after the skin ulcers have been completely cured.
What if I have been exposed to MPX?
Recommendations on recent risk depend on whether the risk is high, medium or low risk.
High risk is defined as close contacts of people who develop MPX. This includes being withing 6 feet for more than three hours, sexual contact or direct contact with body fluids. It can also include contact with shared sheets and towels.
Please self-monitor for symptoms for the next three weeks. This can include taking your temperature twice a day which should stay below 38°C (100.4° F)
Seek medical advice if you develop any of the symptoms above, especially fever, rash, skin bumps, chills or swollen lymph nodes. In the UK this should be by calling a sexual health clinic or by calling 111.
People at higher risk might be offered PEP with vaccination. This will usually be from spending prolonged time with someone with diagnosed MPV or direct contact to ulcers or body fluids.This is only offered to people at high risk.
Also on 21 June 2022, the UKHSA announced that gay and bisexual men at risk of MPX would also be able to access the vaccine. Further details will be announced shortly.
It is important to self-isolate if you develop symptoms and follow health care advice.
What does self-isolation involve?
More detailed information about MPX for people who are self isolating at home were published online on 9 June.
Self isolation involves staying home and reducing contact with other people as much as possible. It involves avoiding public places and not seeing friends and family. Anyone you live with can be at risk. Sleep and eat in separate room and avoid close contact. The guidelines included detailed information about how to clean shared areas, towels and bedding.
You also need to isolate from pets. Someone from the Animal and Plant Health Agency (APHA) with contact you about this,
If you need to leave your home for an emergency, any spots or ulcers need to be completely covered.
The guidance include more details about when you can stop isolating, and additional safety measure like using condoms for the next eight weeks.
Please see this link for full details:
How can I reduce my risk and stay safe?
The current advice for how to reduce your risks is likely to change every week.
This will depend on how successfully MPX is contained or on whether cases continue to rise. This might mean this advice changes, depending on where you live and on different social situations.
This also involves a personal approach to healthcare both for yourself and for the community. For example, to get medical advice if you feel unwell or develop unexpected skin bumps or ulcers. This will also help you access the best care to recover quickly.
One of the higher risks comes from contact with sexual partners, So reducing the numbers of partners, especially in a group setting will help. This is especially important at gay and bisexual venues in London.
Social events that involve being with many people for hours in a poorly ventilated space will be a higher risk than outdoor events with fewer people. This is whether or not anyone is having sex.
This will hopefully only for a short time, perhaps only for the next few weeks.
Will having MPX once protect me against catching it again?
There is currently not enough information to answer this question.
Even if it is possible, this would not be something to rely on before we have data.
Also, cases have been reported when MPX returned after the infection was thought to be cured. When this happens, special tests are needed to know whether this is a new or relapse infection.
3. Diagnosis and treatment?
What if I have symptoms?
If you are worried about symptoms, please telephone a sexual health clinic (or 111 in the UK).
Contact by phone is important. The clinic will ask you about symptoms, including to describe any spots or skin blisters.
Please do NOT visit the clinic using a drop-in service. This could cause health workers to need to isolate and staffing is already under pressure.
Anyone in the UK can access free testing and treatment at a sexual health clinic.
How is MPX diagnosed?
A distinctive spots/blisters appearing a few days after other general symptoms is enough for MPX to be very likely, even before it is confirmed by a test.
This will involve a doctor checking that the skin bumps and blisters are not another infection.
However, testing is still important to rule out other pox viruses.
PCR testing is used to confirm MPX. This involves sending samples to a UK-HSA laboratory. The doctor will need to have your contact details so they can let you know the test result. The UK-HSA is responsible for all MPX cases.
If the sample tests positive, you will be asked about close contacts over the previous three weeks. This includes people you live with and any sexual partners. Sexual partners will not be told about you.
All information is handled privately but please talk to your doctor if you have questions about this.
How important is contact tracing?
Anyone diagnosed with MPX will be asked for details about people they have been in close contact with.
This will help to identify people who might be at risk, and may benefit from PEP.
Effective contact tracing could limit how serious MPX becomes in the UK. It will be done very carefully and sensitively. This is a specialist part of sexual health care.
People who are thought to be at high risk will then be asked to self-monitor for symptoms over the next three weeks. They will be monitored with a daily phone call, and they may be offered vaccination as PEP.
Can MPX be treated?
Yes. Although most people are likely to be monitored without direct treatment.
If needed, several oral drugs were initially being used to treat MPX, especially if symptoms are more than mild.
Of these, tecovirimat (brand name TYPOXX, taken twice daily for 2 weeks) is now the only drug being used in the UK, including in a study.
Neither brincidofovir or cidofovir are thought likely to work. They also have a higher risk of side effects.
As most infections are mild, treatment was originally only offered to more severe cases, or to people at higher risk of severe infection.This can include people with reduced immunity, children younger than eight, pregnancy, and selected other infections.
However, there are plans for tecovirimat to become more widely available at the end of June to anyone diagnosed with MPX. This page will be updated when this happens.
Vaccines are also being used to manage and reduce the symptoms from infection.
How can I manage symptoms if I am isolating at home?
The following suggestions can help manage symptoms and reduce pain.
- Salt water bathing can help reduce the risk of infection and can help ulcers recover more quickly.
- Anaesthetic gels (lidocaine, including brand name Instillagel) can help reduce local pain.
- Over-the-counter pain killers like paracetamol and ibuprofen can reduce pain throughout the body.
- If paracetamol and ibuprofen are not working, try codeine. Stronger formulation can be prescribed by your doctor. This might also involve taking laxatives, if needed.
- To help reduce itching: Over the counter anti-histamines and calamine lotion can both help to reduce itching, If calamine lotion is not available – apparently there is a national shortage – alternatives include crotamiton cream (brand name Eurax) and aloe vera gel.
- Medicated waterproof spot plasters can be used to cover individual ulcers on your skin. This can protect you from scratching or knocking them. It can also limit risk of transmission (to yourself or others).
Please talk to your GP and/or the sexual health clinic to make sure any pain is managed properly. Severe pain can sometimes be managed better in hospital.
Which vaccines are used against MPX?
The main vaccine is called Imvanex (also called Imvamune, Jynneos and MVA).
It is a live but non-replicating vaccine that is also approved against MPX in the US in 2019. This vaccine is safe to use by people living with HIV. It is given in two doses, 28 days apart.
Although the vaccine is safe, anyone with a CD4 count below 100 might be unlikely to generate an effective response.
An earlier vaccine called ACAM2000 was approved in 2007 but is a live replication-competent vaccine. Although it is given as a single dose it is not recommended in people living with HIV. It is also no longer available in the UK.
Are the vaccines effective?
The Imvanex vaccine is likely to help even if given after contact. It should limit the risk of infection or limit the severity of illness if the infection develops.
Vaccine efficacy is approximately 45% after one shot and 85% after two shots. Due to limited supplies, vaccination in the UK might only use a single shot. This might change later.
Vaccination for close contacts is most effective when given within four days of contact. However, it might still be effective for up to 14 days after.
Will smallpox vaccinations from childhood still be active?
Many adults older than 50 will have had the smallpox vaccine as a child.
Even though antibody responses drop over time, childhood vaccination may help against MPV.
Smallpox vaccinations were stopped in the UK in 1971 and immune responses become lower after 10-20 years. As with COVID vaccines, cellular immune responses might last for much longer.
Will vaccines be offered as PrEP, including to gay and bisexual men?
Some countries, including the UK, are using vaccines to protect people at high risk.
This can include close contacts of people diagnosed with MPX, including household contacts.
With limited vaccine supplies, health workers might also be offered a vaccine. This is because they could be at higher risk of contact from people who have not yet been diagnosed with MPX.
However, on 21 June 2022, the UK announced that some gay and bisexual men would now be offered the vaccine. The limited vaccines supplies (currently only 20,000 doses) might mean that will only involve one injection, at least at first.
A single injection is about 45% effective. This increases to 85% after two injections, given 28 days apart.
4. HIV and MPX
How does HIV affect MPX?
The British HIV Association (BHIVA) published a recent statement on MPX, that has also been updated.
This says that HIV should not increase your risk of catching MPX. It also should not make MPV a more serious infection.
So far, HIV is not linked to any difference in symptoms and outcomes. This is based on you having an undetectable viral load and a CD4 count that is well above 200 cells/mm3. This is a cautious approach because there is too little direct evidence about this.
However, roughly half over the MPX cases have been in men who are living with HIV.
The BHIVA statement also references a Nigerian study with worse outcomes for people living with HIV. Most of these cases were not on effective ART though, some with very low CD4 counts and most with detectable viral load.
Please see this link to BHIVA and ECDC statements about MPX.
5. Other questions
What are the differences between MPX and COVID?
Although everyone will worry about the similarities to COVID-19.
There are important differences that will stop MPX from becoming a pandemic.
- MPX only becomes infectious after there are symptoms. COVID was devastating because it was infectious several days before anyone had symptoms.
- MPX is heavier than the COVID virus, MPV is heavier. This makes it more likely to fall to the ground rather than stay in the air.
- COVID infection was through the nose, throat and lungs. Although MPX can be caught from droplets in air in a confined space, but is more commonly caught by physical contact.
- MPX is much less likely to mutate into different strains than COVID.
- COVID was a more severe infection. Many people needed time in intensive care and in the most serious outcomes, people of all ages died.
What about transmission to animals?
This is an important concern with MPV.
Despite the name, MPX is more linked to infections in other animals. This includes in mice, rats and squirrels.
An outbreak in the US in 2003 was linked to prairie-dogs (which are not dogs).
The concern about other animals being carriers for MPX is that this might make it difficult to control the virus in the long-term.
It is also important for people who self-isolate at home to know whether this also needs to be from their pets. Advice was not initially given on this question, However, on 27 May the UK included the need for people diagnosed with MPX to also isolate from their pets. Similar guidance is made by the ECDC.
This is to reduce the risk that animals could become a long-term reservoir for MPV.
Gerbils, hamsters and other rodents have a very high risk of catching MPX. Other pets including cats and dogs should be kept isolated at home. However, it is difficult to set how “regular vet checks to ensure no clinical signs are observed” is expected to work.
People with pets with be contacted by the Animal and Plant Health Agency (APHA) with with more information.
How worried should we be about MPX?
The WHO responded quickly to the recent news about MPX with two early reports on 21 and 30 May.
These recognised that what happens over the next few weeks will be very important. Currently the organisation says the MPX is a moderate risk to global health.
With more that 6100 cases now reported in non endemic countries, MPX is expanding to a more significant outbreak. The pattern of rapidly increasing seen in the UK, Spain and Portugal is likely to be repeated in other high income countries with similar social structures.
Many are unlikely to have the same resources and access to vaccines that are now being used for prevention. This makes it likely that international travel will continue to spread MPX.
Luckily, MPX infections are still generally mild and no deaths have been reported from these cases.
6. References and further information
The following sources were used for the information on this page and/or are useful links for further information.
- NHS. Monkeypox.
Non-technical information about MPV in the UK. This includes who to contact if you are worried about symptoms.
- UK Health Security Agency (UK-HSA). Monkeypox virus. (23 May 2022).
More detailed information from the UK government about all aspects of MPV including update on the current outbreak.
- BHIVA rapid statement on monkeypox virus. (17 May 2022, updated 31 May 2022).
- European Centre for Disease Prevention and Control (ECDC). Monkeypox multi-country outbreak: rapid assessment report. (23 May 2022).
https://www.ecdc.europa.eu/en/publications-data/risk-assessment-monkeypox-multi-country-outbreak (download page)
See also this slide set from an informal webinar given on 24 May 2022.
Monkeypox ECDC webinar (PDF)
- Adler H et al. Clinical features and management of human monkeypox: a retrospective observational study in the UK. The Lancet, DOI: 10.1016/S1473-3099(22)00228-6. (May 24 2022).
Details of seven MPV cases reported in the UK between 2028 and 2021.
- US CDC. What clinicians need to know about monkeypox in the United States and other countries.
This US talk on clinical management includes pictures of MPV compared to other common skin reactions.
- US CDC. Monitoring people who have been exposed.
- US CDC. Home page for information for doctors about MPV.
- International Monkeypox case tracker. [Kraemer MUG et al. Lancet Inf Dis, DOI: 10.1016/S1473-3099(22)00359-0]
- Human Animal Infections and Risk Surveillance group (HAIRS). Qualitative assessment of the risk to the UK human population of monkeypox infection in a canine, feline, mustelid, lagomorph or rodent UK pet. (27 May 2022).
- Prepster and the UK Health Security Agency (HSA). Two UK Community webinars available online.
https://www.youtube.com/watch?v=9_xz-KTMpHk (26 May 2022).
https://www.youtube.com/watch?v=I0o8FG5MYLw (6 June 2022).
Two excellent early community discussions.
- UK Health Security Agency (UK-HSA). Principles for monkeypox control in the UK: 4 nations consensus statement. (30 May 2022).
Includes updated guidelines for continued prevention in the UK.
- WHO. Multi-country monkeypox outbreak in non-endemic countries: Update. (29 May 2022).
Detailed review of international cases and guidelines for appropriate monitoring and prevention.
- EACS/ECDC. Informal webinar given on 24 May 2022.
Monkeypox EACS/ECDC webinar 1 (PDF)
- EASC/ECDC. Informal webinar given on 31 May 2022.
Monkeypox_EACS/ECDC_webinar 2 (PDF)
- (2 Jun 2022).
. Epidemiological, clinical and virological characteristics of four cases of monkeypox support transmission through sexual contact, Italy, May 2022. Euro Surveill. 2022;27(22):pii=2200421.
- Monkeypox Outbreak — Nine States, May 2022. Minhaj FS et al. MMWR Morb Mortal Wkly Rep 2022;71:764–769. DOI: http://dx.doi.org/10.15585/mmwr.mm7123e1.
- UK Health Security Agency (UK-HSA). Monkeypox: infected people who are isolating at home Information for people who have been diagnosed with a monkeypox infection and who have been advised to self-isolate at home. (9 June 2022).
- US CDC. Disinfection of the Home and Non- Healthcare Settings. (6 June 2022).
- Patrocinio-Jesus R et al. Monkeypox Genital Lesions. NEJM. DOI: 10.1056/NEJMicm2206893. (15 June 2022).
- UK plans to offer vaccine to gay and bisexual men at risk of monkeypox. HTB (21 June 2022).
- UKHSA press release. Monkeypox vaccine to be offered more widely to help control outbreak. (21 June 2022).
- Grosenbach DW et al. Oral Tecovirimat for the Treatment of Smallpox List of authors. N Engl J Med 2018; 379:44-53. DOI: 10.1056/NEJMoa1705688. (5 July 2018).
- JAMA. Global monkeypox outbreaks spur drug research for the neglected disease. JAMA review. doi:10.1001/jama.2022.11224. (29 June 2022).
This information was posted on 26 May 2022 and will be updated as new information becomes available.Last update 2 July 2022.