Understanding Monkeypox Infections

What you need to know

Monkeypox: what do you need to know? Monkeypox: what do you need to know?
Peter Teska
Global Infection Prevention Expert
Jun 01, 2022

Understanding Monkeypox Infections


What you need to know

 

  • The latest data from World Health Organization’s Member States to 22 May, indicates there have been more than 250 confirmed and suspected cases of monkeypox from 16 countries
  • Monkeypox infection is a rare disease, but not new. There are vaccines and therapeutics available
  • Transmission of the virus is not easy to do, so when people are infectious they are showing signs and symptoms and person to person transmission involves contact with body fluids including saliva.

 

Why it matters

  • With the right level of awareness and preventative measures, this virus can easily be contained

 

What our customers can do

  • Observe recommended hygiene practices as discussed below
  • Hand hygiene with soap and water or alcohol based hand rub are effective in removing the virus from hands
  • Surface disinfection with a product carrying a vaccinia claim or EN 14476 against vaccinia virus (Europe), demonstrated efficacy against a harder-to-kill virus, or qualified for the emerging viral pathogens claim (EVP).*

 

Overview: 

Monkeypox infection is a viral zoonotic (animal to human transmission) disease caused by the monkeypox virus which is part of the Orthopoxvirus genus of viruses, which includes smallpox (variola virus). The monkeypox virus was first identified in 1958 in monkeys, which is how the name was derived, and the first case in people was recorded in 1970 in the Democratic Republic of the Congo during the smallpox eradication efforts. 


Historical genetic testing has shown that the monkeypox virus mutates slowly over time and having received a smallpox vaccination within the prior 3 years is estimated to be 85% effective in preventing monkeypox infection. However global vaccination for smallpox stopped in the 1970s when smallpox was eradicated globally. Since the 1990s the number of monkeypox cases has steadily increased as detection has improved. Global travel has increased the spread of diseases, children are no longer being vaccinated for smallpox, and adults experience waning immunity over time.


As of May 24, 2022 there is currently an outbreak of Monkeypox with 250 confirmed and suspected cases reported in 16 countries including the regions of North America, Europe, and Australia. Approximately 1/3 of infected people required hospitalization, suggesting there are more cases where people have milder symptoms and have not sought medical care.


Reservoir: 

The natural reservoir is not established but believed to involve rodents. However, efforts to find the virus in rodents and other animals have only rarely found the virus. It is possible there is another yet to be identified reservoir that is the primary reservoir, but the reservoir is not believed to be people. 


Disease: 

The symptoms of monkeypox infection are similar to those of smallpox (but generally milder), making it difficult to distinguish between the two initially. Only a trained physician should attempt to diagnose monkeypox infections as this initial presentation of signs and symptoms can be very similar to other infections and a physician can arrange for testing to conclusively diagnose monkeypox infection.


Transmission: 

The monkeypox virus can enter the body through broken skin, the respiratory tract, or mucous membranes. The virus is not believed to be easily passed from person to person since a large dose of virus is believed to be needed to cause transmission to another person. 

  • Human to human transmission can occur through (intimate) contact transmission with infected body fluids or droplet transmission of infected large respiratory droplets/respiratory secretions (from prolonged face to face contact). If infected respiratory droplets are inhaled, ingested, or otherwise enter the body, this can result in infection. Indirect contact with contaminated shared items and contaminated bedding can also transmit the virus. Mother to fetal transmission can occur via the placenta in the uterus or during birth. 
  • Animal to human transmission can occur through the bite or scratch of an infected animal, while consumption of infected animal meat can also result in infection. Infection can also result from exposure to contaminated animal blood or body fluids, such as through slaughter and preparation of an infected animal for consumption or the contamination of surfaces with infected blood or body fluids, such as surfaces in the home or bedding that has become contaminated with infected urine or feces from an infected animal.

The incubation period is typically 6-13 days, but can range from 5-21 days, so a significant amount of time can pass between exposure and the first signs or symptoms. In general, pox viruses are not likely to be transmitted between people until signs or symptoms occur, so asymptomatic transmission is not believed to be likely. 


Signs and Symptoms: 


Initial symptoms include:

  • Fever/chills
  • Headache
  • Swollen lymph nodes
  • Muscle Aches/backache
  • Fatigue/exhaustion

Typically 1-3 days after the onset of fever, the infected person develops a rash on the face, palms of hands, and bottom of feet. Other areas of the body can develop rash over time. Pustules/lesions from the rash contain fluid with high concentrations of virus and are believed to be the main source of subsequent person to person transmission.


The main initial difference between monkeypox and smallpox infection is that monkeypox causes the lymph nodes to swell, while smallpox does not. Within 1-3 days of the start of fever, people infected with monkeypox usually develop a rash often beginning on the face and then spreading to other parts of the body, during which time lesions develop, scab, and fall off. The infection typically lasts 2-4 weeks and has a 1-10% mortality rate. Prompt medical care can significantly reduce the risk of mortality as there are highly effective therapeutics available. Hospitalization is more likely in children than adults. 


There is a new vaccine that helps prevent monkeypox infections, but it is not widely distributed currently. As mentioned above, prior smallpox vaccination provides some measure of protection in preventing monkeypox infection as well for those vaccinated prior to 1980, although immunity has likely waned over time. 


Prevention: 


The primary methods of prevention include:

  • People suspected of being infected with monkeypox should be isolated from other people and should seek medical care immediately. People exposed to infected people should also consult a physician to determine whether quarantine is needed to ensure they have not been infected.
  • If in contact with an infected person or animal, hand hygiene should be performed frequently to help minimize the risk of infection and face masks should be worn, especially where there is prolonged contact. Showering and laundering clothing from the contact are also sensible precautions.
  • As the monkeypox virus is an enveloped virus, it is highly susceptible to alcohol-based hand rubs (at least 60% alcohol) and disinfectants (carrying enveloped virus claims such as vaccinia virus). 
  • Healthcare workers caring for patients known or suspected of having monkeypox should wear appropriate personal protective equipment and use contact and droplet transmission-based precautions in addition to standard precautions. Airborne precautions may also be appropriate if available since there is a theoretical risk of airborne transmission. 
  • Avoid unprotected contact with animals that could harbor the virus including those that are sick or dead in areas suspected of having the monkeypox virus.
  • Avoid contact with materials, such as bedding, that have been in contact with a sick animal or person.


References:

For more information, these websites are good sources for information and were used to prepare this document.


World Health Organization: https://www.who.int/news-room/fact-sheets/detail/monkeypox
US-Centers for Disease Control and Prevention: https://www.cdc.gov/poxvirus/monkeypox/index.html

*Please follow country regulations to determine what is appropriate at the local level.