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WHAT IS MONKEYPOx?

Monkeypox is a disease of global public health importance1

  • Monkeypox is an emerging infectious disease with steady increases in outbreak frequency and expected outbreak size in humans2
  • Since the eradication of smallpox in 1980, monkeypox has emerged as the most important orthopoxvirus for public health1
  • It is a viral disease caused by the monkeypox virus, which belongs to the same family of viruses as the smallpox, cowpox, and vaccinia viruses. Two distinct monkeypox virus clades exist, the Clade I and Clade II.1,3
  • In July 2022, WHO declared that the global monkeypox outbreak represents a public health emergency of international concern.14

Monkeypox was first discovered in 1958 in monkeys kept for research, hence the name ‘monkeypox’3

MONKEYPOX IS NOT NEW BUT OUR UNDERSTANDING IS STILL EVOLVING1,2,4

In Africa

  • The first human case of monkeypox was recorded in 1970 in the Democratic Republic of the Congo (DRC).3 Until the recent outbreaks, monkeypox had been reported in 10 countries.4
  • The number of human monkeypox cases has been on the rise since the 1970s.5 Outbreaks in Nigeria, Cameroon, and DRC continue today.6,7

Global Spread

  • The geographic spread of monkeypox cases from the forests of central Africa where the initial cases were found has expanded, via travelers, to other parts of the world.1,2,4

*Cameroon, Central African Republic, Côte d’Ivoire, Democratic Republic of the Congo, Gabon, Liberia, Nigeria, Republic of the Congo, Sierra Leone and South Sudan.4
†See global spread map and the current situation at https://monkeypox.healthmap.org/. Accessed July 2022. DRC, Democratic Republic of the Congo; ROW, rest of world; UK, United Kingdom; US, United States of America.

MONKEYPOX IS CURRENTLY SPREADING TO NON-ENDEMIC AREAS6,7,9,11

Between January 1, 2022 and October 18, 2022, 73,604 cases of monkeypox have been confirmed in 103 countries, with few deaths in non-endemic countries, and these numbers may continue to evolve.12

On July 23, 2022 WHO declared that the global monkeypox outbreak represents a public health emergency of international concern.5

Unlike previous monkeypox cases in Europe, most cases in the current outbreak are in people who have not traveled to the parts of Africa where monkeypox is endemic.

TRANSMISSION AND CLINICAL PRESENTATION

Initially, several infected people attended the same events, where they had close or sexual contact with others.5 Many patients in this outbreak are not presenting with the classical clinical picture for monkeypox, instead, the common presenting symptoms include genital and peri-anal lesions, fever, swollen lymph nodes, and pain when swallowing.7

MONKEYPOX OUTBREAK GLOBAL MAP12 (As of September 12, 2022)

MONKEYPOX CAN BE TRANSMITTED THROUGH CLOSE CONTACT BETWEEN PEOPLE5,7

Human-To-Human Transmission

  • Monkeypox does not spread easily between people,5 and does so primarily through direct contact with infectious sores, scabs, or body fluids, or with materials contaminated with the virus, such as clothing or linens8,9
  • Monkeypox can be passed on from mother to child, or spread during intimate contact between people, including sexual activities
  • It is not yet known if monkeypox can spread through semen or vaginal fluids8

Animal-To-Human Transmission1,6

In endemic countries, monkeypox can spread from animals to people via:8

  • A bite or scratch from an infected animal
  • Handling or eating wild game
  • Using products made from infected animals

Various animal species have been identified as susceptible to monkeypox virus,1 and further studies are needed to identify its exact natural history.1,6

MONKEYPOX DISEASE COURSE1

INCUBATION PERIOD

6–13 days
(range 5–21 days)

INFECTION PERIOD

Invasion (0–5 days)
Skin Eruptions (1–3 days after fever starts)

FEVER
INTENSE HEADACHE
BACK PAIN
Lymphadenopathy
Myalgia
Intense physical weakness
Lesions

THE NUMBER OF LESIONS RANGES FROM VERY FEW TO SEVERAL THOUSAND1

  • In humans, monkeypox symptoms are similar to but milder than smallpox symptoms.10 Swollen lymph nodes are a distinctive feature of monkeypox, compared with apparently similar diseases (chickenpox, measles, smallpox)1
  • There can be very few to thousands of lesions, which are concentrated on the face and extremities1
  • The lesions progress from flat, red bumps to becoming raised and pus-filled, before drying out and falling off1

Monkeypox is usually a self-limited disease with symptoms lasting from 2 to 4 weeks1

MOST FREQUENTLY AFFECTED AREAS, HISTORICALLY*1

In Africa, monkeypox has been shown to cause death in as many as 1 in 10 cases.4 Fatality rates are higher from Clade I than Clade II (10.6% vs 3.6%).4

Severe cases can occur more commonly among children, young adults, and people who are immunocompromised.1 This is due largely to vaccination against smallpox (which also offers protection against monkeypox) being stopped after it was eradicated.1,5

Complications of monkeypox can include secondary infections, bronchopneumonia, sepsis, encephalitis, and infection of the cornea with ensuing loss of vision.1

*Historic pattern. Genitalia seem more commonly affected in the current outbreak.7
†Conjunctivae and corneas.

AM I AT RISK?

People who may be at risk include (but are not limited to) those who:15

  • Live with or have close contact (including skin-to-skin contact) with someone who has been diagnosed with confirmed or probable monkeypox
  • Have regular contact with animals that could be infected

Newborn infants, young children and people with underlying immune deficiencies may be at risk of more serious symptoms and death from monkeypox.15

Infected people should remain isolated until scabs fall off and should especially avoid close contact with young children, pregnant women, immunocompromised persons, and pets.5

Protecting Yourself

Reduce your risk of catching monkeypox by limiting close contact with people who have suspected or confirmed monkeypox. Keep yourself informed about monkeypox in your area or social group and have open conversations with those you come into close contact (especially sexual contact) with about any symptoms you or they may have. Clean your hands frequently with soap and water or an alcohol-based hand rub.

Frequently clean and disinfect commonly touched surfaces in the environments that could have been contaminated with the virus from someone who is infectious. In countries where animals carry monkeypox, protect yourself by avoiding unprotected contact with wild animals. Any foods containing animal parts or meat should be cooked thoroughly before eating.

Vaccination against monkeypox is recommended for persons at risk (for example someone who has been a close contact of someone who has monkeypox). If you think you might have monkeypox, you can act to protect others by seeking medical advice and isolating from others until you have been evaluated and tested.15

If you have any monkeypox symptoms, talk to your healthcare provider, even if you believe you have not been in contact with an infected person11

References

  1. WHO. Monkeypox. Available at https://www.who.int/news-room/fact-sheets/detail/monkeypox. Accessed July 2022.
  2. Grant R, et al. Bull World Health Organ. 2020;98:638–640
  3. CDC. About monkeypox. Available at https://www.cdc.gov/poxvirus/monkeypox/about.html. Accessed July 2022.
  4. Bunge EM, et al. PLoS Negl Trop Dis. 2022;16(2):e0010141.
  5. ECDC. Questions and answers on monkeypox. Available at https://www.ecdc.europa.eu/en/monkeypox/questions-and-answers. Accessed July 2022.
  6. WHO. Multi-country monkeypox outbreak in non-endemic countries. Available at https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON385. Accessed July 2022.
  7. WHO. Multi-country monkeypox outbreak: situation update. Available at https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON396. Accessed July 2022.
  8. CDC. Monkeypox: How it spreads. Available at https://www.cdc.gov/poxvirus/monkeypox/transmission.html. Accessed July 2022.
  9. ECDC. Factsheet for health professionals on monkeypox. Available at https://www.ecdc.europa.eu/en/all-topics-z/monkeypox/factsheet-health-professionals. Accessed July 2022.
  10. CDC. Monkeypox: Signs and symptoms https://www.cdc.gov/poxvirus/monkeypox/symptoms/. Available at Accessed July 2022.
  11. CDC. U.S. Monkeypox 2022: Situation summary. Available at https://www.cdc.gov/poxvirus/monkeypox/response/2022/index.html. Accessed July 2022.
  12. CDC. 2022 Monkeypox outbreak global map. Available at https://www.cdc.gov/poxvirus/monkeypox/response/2022/world-map.html. Accessed July 2022.
  13. CIDRAP. Non-endemic countries record first monkeypox deaths. Available at https://www.cidrap.umn.edu/news-perspective/2022/08/non-endemic-countries-record-first-monkeypox-deaths. Accessed August 2022.
  14. WHO. Second meeting of the International Health Regulations (2005) (IHR) Emergency Committee regarding the multi-country outbreak of monkeypox. Available at https://www.who.int/news/item/23-07-2022-second-meeting-of-the-international-health-regulations-(2005)-(ihr)-emergency-committee-regarding-the-multi-country-outbreak-of-monkeypox. Accessed August 2022.
  15. WHO. Monkeypox. Available at https://www.who.int/news-room/questions-and-answers/item/monkeypox. Accessed August 2022.