MONKEYPOX

Monkeypox is a viral zoonotic disease that occurs primarily in tropical rainforest areas of central and west Africa. Cases of Monkeypox have also been reported in non-endemic regions including Europe, United States and Australia. The monkeypox virus is a double-stranded DNA enveloped virus and can be transmitted from animal to human, human to human and via contaminated surfaces.

WHAT IS MONKEYPOX?

Monkeypox is a viral zoonotic disease caused by infection with monkeypox virus. It is an enveloped double-stranded DNA virus in the genus Orthopoxvirus within the family Poxviridae1,2. Other members of the genus are variola virus (smallpox), vaccinia virus (used in the smallpox vaccine), and cowpox virus. Monkeypox was first discovered in 1958 in colonies of research monkeys following two outbreaks of pox-like disease. In 1970 the first human case of monkeypox occurred in the Democratic Republic of Congo and continues to occur primarily in tropical rainforest areas of central and west Africa. Since 2017, Nigeria has experienced a large outbreak, with over 500 suspected cases and over 200 confirmed cases and a case fatality ratio of approximately 3%1. It is occasionally reported in other regions. In 2003, the first monkeypox outbreak outside of Africa occurred in the United States of America, with over 70 cases that were linked to contact with infected pet prairie dogs. Monkeypox has been reported in travelers from Nigeria to Israel in September 2018, to the United Kingdom in September 2018, December 2019, May 2021 and May 2022, to Singapore in May 2019, and to the United States of America in July and November 2021. In May 2022, multiple cases of monkeypox were identified in several non-endemic countries. Studies are currently underway to further understand the epidemiology, sources of infection, and transmission patterns1.

WHAT ARE THE SYMPTOMS?

Monkeypox is usually a self-limited disease with the symptoms lasting from 2 to 4 weeks. Monkeypox is less contagious than smallpox and causes less severe illness. It typically presents clinically with fever, rash and swollen lymph nodes. Severe cases occur more commonly among children and are related to the extent of virus exposure, patient health status, and nature of complications. Underlying immune deficiencies may lead to worse outcomes. In recent times, the case fatality ratio has been around 3–6%1.

HOW IS IT TRANSMITTED?

Transmission of monkeypox virus can occur when a person comes into contact with the virus from an infected animal, human, or materials/surfaces contaminated with the virus. The virus can enter the body through broken skin, respiratory tract, or the mucous membranes (eyes, nose, or mouth). Zoonotic or animal-to-human transmission may occur through a bite or scratch, bush meat preparation, direct contact with body fluids or lesion material, or indirect contact with lesion material, such as through contaminated bedding. Human-to-human transmission is thought to occur mainly through large respiratory droplets, for example if engaging in prolonged face-to-face contact with an infected individual. Other human-to-human methods of transmission include via the placenta from mother to fetus, direct contact with body fluids or lesion material, and indirect contact with lesion material, such as through contaminated clothing or linens1

The reservoir host (main disease carrier) of monkeypox is still unknown but African rodents are suspected to play a part in transmission2.

HOW IS IT CONTROLLED?

Surveillance, rapid detection, raising awareness of risk factors and educating people about measures they can take to reduce exposure are the main ways to control Monkeypox. There are number of measures that can be taken to prevent infection with monkeypox virus: 

  • Practice enhanced precautions when travelling in areas experiencing outbreaks of Monkeypox
  • Avoid contact with animals that could harbor the virus (including animals that are sick or that have been found dead in areas where monkeypox occurs).
  • Avoid contact with any materials, such as bedding, that has been in contact with a sick animal.
  • Isolate infected patients from others who could be at risk for infection.
  • Practice good hand hygiene after contact with infected animals or humans. For example, washing your hands with soap and water or using an alcohol-based hand sanitizer.
  • Use personal protective equipment (PPE) when caring for patients. 

During human monkeypox outbreaks, health workers and household members of an infected person are at a greater risk of infection due to the likelihood of prolonged close contact.  

During an outbreak in a healthcare setting a combination of standard, contact, and droplet precautions should be applied for Monkeypox patients. The following precautions should also be used to control the spread of the virus3

  • Proper hand hygiene after all contact with an infected patient and/or their environment during care. 
  • Correct containment and disposal of contaminated waste (e.g., dressings) in accordance with facility-specific guidelines for infectious waste or local regulations pertaining to household waste.
  • Care when handling soiled laundry (e.g., bedding, towels, personal clothing) to avoid contact with lesion material.
    • Soiled laundry should never be shaken or handled in manner that may disperse infectious particles. 
    • Soiled linens can be disinfected using an EPA-registered laundry disinfectant with an Emerging Viral Pathogen claim 
  • Care when handling used patient-care equipment in a manner that prevents contamination of skin and clothing. 
    • Ensure that used equipment has been cleaned and reprocessed appropriately. 
  • Ensure procedures are in place for cleaning and disinfecting environmental surfaces in the patient care environment. 
    • An EPA-registered hospital disinfectant with an Emerging Viral Pathogen claim, currently used by healthcare facilities for environmental disinfection, may be used. Follow the manufacturer’s recommendations for concentration, contact time, and care in handling.

REFERENCES AND FURTHER INFORMATION

  1. Monkeypox (who.int) 
  2. Monkeypox | Poxvirus | CDC
  3. Infection Control: Hospital | Monkeypox | Poxvirus | CDC