Monkeypox virus is a zoonotic viral disease that occurs primarily in remote villages of Central and West Africa in proximity to tropical rainforests where there is more frequent contact with infected animals. It is a viral disease that produces pox lesions on the skin and is closely related to smallpox but is not nearly as deadly as smallpox.
Monkeypox is a relatively rare disease and was first discovered in 1958 when two outbreaks of a pox-like disease occurred in colonies of monkeys kept for research, hence the name ‘monkeypox.’ The first human case of monkeypox, a 9-year-old boy, was recorded in 1970 in the Democratic Republic of Congo during a period of intensified effort to eliminate smallpox (Smallpox was later eradicated from the human population by vaccinations in 1979). Since then monkeypox has been reported in humans in other central and western African countries. A 2003 outbreak in the United States is the only time monkeypox infections in humans were documented outside of Africa.
Monkeypox is caused by infection with monkeypox virus. Monkeypox virus belongs to the Orthopoxvirus genus in the family Poxviridae. The Orthopoxvirus genus also includes variola virus (the cause of smallpox), vaccinia virus (used in the smallpox vaccine), and cowpox virus.
The natural reservoir of monkeypox remains unknown. However, African rodent species are expected to play a role in transmission.
How is Monkeypox Transmitted?
Transmission of monkeypox virus occurs when a person comes into contact with the virus from an animal, human, or materials contaminated with the virus.
The virus enters the body through broken skin (even if not visible), respiratory tract, or the mucous membranes (eyes, nose, or mouth). Animal-to-human transmission may occur by 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 primarily through large respiratory droplets. Respiratory droplets generally cannot travel more than a few feet, so prolonged face-to-face contact is required. Other human-to-human methods of transmission include direct contact with body fluids or lesion material, and indirect contact with lesion material, such as through contaminated clothing or linens.
Signs and Symptoms In humans, the symptoms of monkeypox are similar to but milder than the symptoms of smallpox.
Monkeypox begins with:
Swollen lymph nodes
The main difference between symptoms of smallpox and monkeypox is that monkeypox causes lymph nodes to swell (lymphadenopathy) while smallpox does not. The incubation period (time from infection to symptoms) for monkeypox is usually 7−14 days but can range from 5−21 days.
Within 1 to 3 days (sometimes longer) after the appearance of fever, the patient develops a rash, often beginning on the face then spreading to other parts of the body.
Lesions progress through the following stages before falling off:
The illness typically lasts for 2−4 weeks. In Africa, monkeypox has been shown to cause death in as many as 1 in 10 persons who contract the disease.
What can I do to manage my symptoms?
Eat a variety of healthy foods. Healthy foods include fruits, vegetables, whole-grain breads, low-fat dairy products, lean meats, fish, and beans. Healthy foods may help you feel better and have more energy.
Rest as needed. You may feel like resting more. Slowly start to do more each day. Rest when you feel it is needed.
How is Monkeypox Diagnosed?
Your healthcare provider will examine you and ask about your symptoms. Tell him if you had any recent animal bites. Tell him if you have recently cared for or visited a person who has monkeypox.
You may also need any of the following:
Blood tests are used to check for the monkeypox virus.
A biopsy is a procedure used to take a sample to be tested. Healthcare providers may collect samples of skin, fluid from the blisters, or crust from the sores. These samples will be tested for the monkeypox virus.
A throat swab culture is used to take a sample from your throat to be tested for the virus. A throat culture is done by rubbing a cotton swab on the back of your throat.
What is the Treatment for Monkeypox?
There is no specific treatment or vaccine available, though the use of smallpox vaccine is recommended for the treatment of monkeypox because it is so closely related to smallpox. Treatment with an antiviral drug or human immune globulin has been recommended.
The CDC recommends the following:
A smallpox vaccination should be administered within two weeks of exposure to monkeypox.
Cidofovir (Vistide), an antiviral drug, is suggested for patients with severe, life-threatening symptoms.
Vaccinia immune globulin may be used, but efficacy of use has not been documented.
For severe symptoms, supportive measures such as mechanical ventilation may rarely be needed. Consultation with an infectious-diseases expert and the CDC is recommended.
What is the Prognosis of Monkeypox?
The usual prognosis of patients with monkeypox is good to excellent. Many patients have mild symptoms. However, patients with immune or other compromised health problems such as malnutrition, lung problems, may develop complications of secondary bacterial infections, pneumonia, and dehydration. Older estimations of a 10% death rate were published, but in the last 10-15 years, this has been revised to less than 2% of infected individuals, with the worst cases originating from animal-to-human infection, not person to person.
Prevention of Monkeypox
Monkeypox is preventable as long as people avoid direct contact with infected animals and people.
Measures that can be taken to prevent infection with monkeypox virus include:
Avoid contact with animals that could harbour 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.
Because smallpox and monkeypox are so closely related, studies have suggested that people vaccinated against smallpox have about an 85% chance of being protected from monkeypox. Consequently, the CDC recommends the following:
Patients with depressed immune systems and those who are allergic to latex or smallpox vaccine should not get the smallpox vaccine.
Anyone else who has been exposed to monkeypox in the past 14 days should get the smallpox vaccine, including children under 1 year of age, pregnant women, and people with skin conditions.
There is no commercially available vaccine designed specifically for monkeypox. Research is ongoing to study antivirals, genetics, and rapid tests for monkeypox.
How do I safely care for someone who has monkeypox?
Have the person stay in one part of the home. Do not allow visitors or pets in that area if possible. Have the person wear a mask when other people are in the room. Everyone should wear a mask when in the person's room.
Wash your hands before and after you go into the person's room. Frequently clean all items and surfaces touched by the person. Use a household cleanser that kills germs. Use disposable (single-use) gloves while you clean, wash, or handle bedding, eating utensils, or used tissues. Only use the gloves once and then throw them away. Wash your hands after you wear the gloves.
Do not share beddings, linens, or eating utensils with the person. These items may be used again after they have been cleaned with hot water and soap.
Pay close attention to how you feel. See your healthcare provider if you get a fever, rash, or start feeling sick within 3 weeks of being exposed to monkeypox.