Mpox (monkeypox) is an infectious disease caused by the monkeypox virus (MPXV). It can cause painful rash, enlarged lymph nodes and fever. Most people fully recover, but some get very sick. Like the other known virus that causes smallpox, it’s a member of the genus Orthopoxvirus. MPXV is an enveloped double-stranded DNA virus of the Orthopoxvirus genus in the Poxviridae family. The two genetic clades of the virus are clades I and II.
It was first discovered in Denmark (1958) in monkeys kept for research and the first reported human case was a nine-month-old boy in the Democratic Republic of the Congo (DRC, 1970). Mpox spreads from person to person or occasionally from animals to people. Following the eradication of smallpox in 1980 and the end of smallpox vaccination worldwide, this virus emerged in central, east and west Africa. The natural reservoir of the virus is unknown. The current world outbreak 2022 to 2023 is caused by Clade IIb, a subtype of the less severe West African clade.
Transmission
Person to person transmission of mpox can occur through direct contact with infectious skin or other lesions such as in the mouth or on genitals. This includes contact;
• Face-to-face
• Skin-to-skin
• Mouth-to-mouth
• Mouth-to-skin contact
• Respiratory droplets or short-range aerosols from prolonged close contact
The virus enters the body through broken skin, mucosal surfaces or via the respiratory tract. Mpox can spread to other members of the household and to sex partners. People with multiple sexual partners are at higher risk.
Animal to human transmission occurs from infected animals to humans from bites or scratches, or during activities such as hunting, skinning, trapping, cooking, playing with carcasses, or eating animals. It can also be contracted from contaminated objects such as clothing or linens, through sharps injuries in health care, or in community setting such as tattoo parlours.
Incubation Period
The incubation period is 3–17 days. During this time, the person is asymptomatic and may feel fine as the rash will go through several stages, including scabs, can initially look like pimples or blisters, painful and itchy before healing.
Signs and Symptoms
The signs and symptoms usually begin within one week but can start 1–21 days after exposure. Symptoms typically last 2–4 weeks but may last longer in someone with weakened immune system. Common symptoms are:
• Rash
• Fever
• Sore throat
• Headache
• Muscle aches
• Back pain
• Low energy/ Lethargy
• Swollen lymph nodes
For some people, the first symptom of is rash, while others may have different symptoms first. The rash begins as a flat sore which develops into a blister filled with liquid and may be itchy or painful. As the rash heals, the lesions dry up, crust over and fall off. Some may have one or a few skin lesions and others have hundreds or more. These can appear anywhere on the body such as the:
• Palms of hands and soles of feet
• Face, mouth and throat
• Groin and genital areas
• Anus.
Some people also have painful swelling of their rectum or pain and difficulty when peeing. People with mpox are infectious and can pass the disease on to others until all sores have healed and a new layer of skin has formed.
Diagnosis
Detection of viral DNA by polymerase chain reaction (PCR) is the best laboratory test. The best diagnostic specimens are taken directly from the rash; skin, fluid or crusts; collected by vigorous swabbing. In the absence of skin lesions, testing can be done on oropharyngeal, anal or rectal swabs.
Treatment and Vaccination
The goal of treating mpox is to take care of the rash, manage pain and prevent complications.
• Early and supportive care is important to help manage symptoms and avoid further problems.
• Mpox vaccine can help prevent infection. The vaccine should be administered within 4 days of contact with someone who has it (or within up to 14 days if there are no symptoms).
• Antivirals such as Tecovirimat, originally developed to treat smallpox have been used.
Self-care and Prevention
It’s self-limited and most people with Mpox will recover within 2–4 weeks. Things to do to help the symptoms and prevent infecting others include the following Dos and Don’ts.
Do
• Stay home
• Wash hands often with soap and water or hand sanitizer, especially before or after touching sores
• Wear a mask and cover lesions when around other people until your rash heals
• Keep skin dry and uncovered (unless in a room with someone else)
• Avoid touching items in shared spaces and disinfect shared spaces frequently
• Use saltwater rinses for sores in the mouth
• Take sitz baths or warm baths with baking soda or Epsom salts for body sores
• Take over the counter medications for pain like paracetamol (acetaminophen) or ibuprofen.
Don’ts
• Pop blisters or scratch sores, which can slow healing, spread the rash to other parts of the body, and cause sores to become infected.
• Shave areas with sores until scabs have healed and you have new skin underneath.
Complications
• Pneumonia
• Corneal infection with loss of vision
• Pain or difficulty swallowing
• Vomiting and diarrhoea causing severe dehydration or malnutrition
• Sepsis (infection of the blood with a widespread inflammatory response in the body).
• Inflammation of the brain (encephalitis), heart (myocarditis), rectum (proctitis), genital organs (balanitis) or urinary passages (urethritis).
• Persons with immune suppression due to medication or medical conditions are at higher risk of serious illness and death due to mpox.
• People living with HIV that is not well-controlled or treated will develop severe disease.
• Death