Overview: Monkeypox is a viral disease caused by the monkeypox virus.
A viral disease caused by the monkeypox virus characterized by fever, rash, and enlarged lymph nodes transmitted through close contact with infected persons, animals, and contaminated objects. Most people recover completely from the disease in 2 to 4 weeks.
Definition
Monkeypox is a viral zoonosis caused by the monkeypox virus. The clinical manifestations are similar to those of smallpox, but less severe.
Monkeypox virus is a species of monkeypox virus in the genus Poxvirus, family Poxviridae. It belongs to the genus Orthopoxvirus together with smallpox virus, cowpox virus, and poxvirus (used in the preparation of smallpox vaccine). These viruses are very similar in terms of antigenicity, biological properties, morphology, structure and resistance.
On July 23, 2022, the World Health Organization (WHO) announced that the monkeypox outbreak was classified as a public health emergency of international concern, the highest level of public health alert issued by the organization globally, and on May 12, 2023, WHO declared that the monkeypox outbreak no longer constituted a “public health emergency of international concern.” The outbreak is no longer a “public health emergency of international concern”.
Incidence
The first human case of monkeypox virus infection was reported in 1970 in Zaire, Central Africa (now the Democratic Republic of the Congo). Since then, cases have been reported from time to time in Africa.
Between 1970 and 1980, 59 human cases of monkeypox were reported in Africa, with a case fatality rate of 17%.
In June 2003, 71 suspected and confirmed cases of monkeypox were identified in the United States.
Between 2005 and 2007, 760 laboratory-confirmed human cases of monkeypox were identified in the Democratic Republic of Congo, with an overall mortality rate of less than 5%.
In July 2021, a case of monkeypox returned from Nigeria was confirmed in Dallas, Texas, USA.
On November 16, 2021, a case of monkeypox returned from Nigeria was confirmed in Maryland, USA.
Between 2017 and 2021, 512 cases of monkeypox were reported in Nigeria.
Between 2018 and May 2022, seven cases of monkeypox were reported in the United Kingdom, most of which were associated with travel to endemic countries.
Between January and April 2022, Nigeria reported 46 cases of monkeypox.
In May 2022, a number of countries, including the United Kingdom and the United States, reported cases of monkeypox. As of May 21, 92 confirmed and 28 suspected cases of monkeypox had been reported in 12 non-monkeypox-endemic countries, including the United Kingdom, Spain, Portugal, and the United States. On the same day, the World Health Organization issued an outbreak warning for monkeypox.
From June 2 to June 30, 2023, 106 new confirmed cases of monkeypox were reported in Mainland China (excluding Hong Kong, Macao and Taiwan), with no serious or fatal cases. The majority of the cases were in men who have sex with men (MSM), mainly transmitted through male-to-male contact, and the majority of close contacts other than sexual contact did not become infected.
Causes
Caused by monkeypox virus, the disease is spread from person to person mainly through close contact, droplet transmission, but also through contact with contaminated objects. If there is no close contact, monkeypox virus can hardly be transmitted from person to person.
Sources of infection
The main source of infection is rodents infected with monkeypox virus. Primates (including monkeys, chimpanzees, humans, etc.) can also be a source of infection.
Route of transmission
From animals to humans
Infection through contact with diseased exudates, blood, or other body fluids of infected animals, or by bites or scratches from infected animals.
Interpersonal transmission
Mainly through close contact, but also through droplet transmission, contact with objects contaminated by the virus may also be infected, but also through the placenta vertical transmission.
Susceptible population
The population is generally susceptible.
People who have been vaccinated against smallpox have some cross-protection against monkeypox virus.
Symptoms
Common symptoms such as rash, fever, sore throat, headache, muscle pain, back pain, malaise, swollen lymph nodes. Some people present early with facial rash, while others present with fever and enlarged lymph nodes.
Main Symptoms
In humans, monkeypox is a sporadic and occasional disease with signs and symptoms similar to smallpox, but usually less severe. Monkeypox symptoms usually last 14 to 28 days.
Incubation period
The incubation period is 5 to 21 days, mostly 6 to 13 days.
There are no obvious clinical symptoms at this stage.
Early onset
Early onset of the disease can be characterized by chills and fever, with body temperature mostly above 38.5°C. It can be accompanied by headache, drowsiness, malaise, back pain and myalgia.
Most patients may have enlarged lymph nodes in the neck, armpit and groin.
Rash stage
Mostly appear in 1~3 days after fever.
The rash first appears on the face and gradually spreads to the limbs and other parts of the body. The rash has a centrifugal distribution, and is more common on the face and limbs than on the trunk, and can appear on the palms of the hands and feet.
The number of rashes varies from a few to thousands; they may also involve the oral mucosa, digestive tract, genitals, conjunctiva and cornea.
The rash undergoes several stages of change from macules, papules, herpes, pustules to scabs. Herpes and pustules are mostly spherical, about 0.5-1 cm in diameter, hard, and may be accompanied by significant itching and pain.
From the onset of the disease to the scabs fall off about 2 to 4 weeks. Erythema or hyperpigmentation or even scarring may remain after the scabs fall off, and the scarring may last up to several years.
Complications
Monkeypox infection may lead to complications such as secondary bacterial infections of the skin, development of corneal lesions, and encephalitis.
Medical care
Infectious diseases and dermatology are usually consulted.
Departments of Medicine
Department of Infection
If people around you have similar symptoms, or if you have a history of close contact with a confirmed patient and develop symptoms such as fever, headache, malaise, rash, and swollen lymph nodes, it is recommended that you consult a doctor promptly.
Dermatology
If a rash develops, you may also visit a dermatologist.
Preparation for medical treatment
Preparing for your visit: registering, preparing your documents, and frequently asked questions.
Tips for seeking medical attention
If you have a rash on your face, it is recommended that you do not wear make-up before your visit so as not to cover up your condition.
The doctor may need to examine more than one area of the skin, so please wear loose-fitting clothing for ease of examination.
Preparation Checklist
Symptom Checklist
Particular attention needs to be paid to the time of onset of symptoms, special manifestations, etc.
Are there any symptoms such as fever, headache, or fatigue?
Is there a rash on the body? If so, where did it first appear?
When did these symptoms appear and in what order did they occur?
Is there a subcutaneous mass on the body?
List of epidemiologic history
Any history of travel in the area where the out-of-state monkeypox case was reported within 21 days prior to onset of illness?
Any close contact with monkeypox cases within 21 days prior to onset of illness?
Any contact with blood, body fluids, or secretions from monkeypox virus-infected animals within 21 days prior to onset of illness?
List of medications used
Medications used in the last 3 months, if available in boxes or packages, bring with you to the doctor’s office
Antipyretics and analgesics: ibuprofen, acetaminophen
Diagnosis
Diagnosis is usually confirmed by initial suspicion through history of exposure and symptoms, followed by nucleic acid testing or virus isolation.
Diagnosis is based on
Epidemiologic history
Direct contact with blood, body fluids, or secretions of monkeypox virus-infected animals within 21 days prior to onset of illness.
Close contact with a monkeypox case within 21 days prior to onset of illness.
History of traveling outside of the reporting area of monkeypox cases within 21 days prior to onset of illness.
Clinical manifestations
Early onset of the disease may show symptoms similar to upper respiratory tract infections, such as fever, headache, malaise and so on.
Rash may appear after 1~3 days of fever, and the rash undergoes several stages of changes from macular rash, papule, herpes, pustule to scab, which may be accompanied by obvious itching and pain, and it takes about 2~4 weeks from the onset of the disease to the shedding of the scabs.
Laboratory Tests
Blood routine, blood biochemistry examination
There may be normal or elevated peripheral blood leukocytes and normal or decreased platelets.
Some patients may have elevated aminotransferases, decreased blood urea nitrogen, and decreased albumin.
Nucleic acid test
Nucleic acid can be detected by nucleic acid amplification assay in specimens such as rash, blisters, scabs, oropharyngeal or nasopharyngeal secretions.
Virus culture
Rash, blister, scab, oropharyngeal or nasopharyngeal secretions and other specimens can be collected for virus culture to isolate monkeypox virus.
Virus culture should be performed in a biosafety laboratory of Level III or above.
Diagnostic criteria
For cases meeting the criteria of suspected cases or confirmed cases, infectious disease reports should be made according to relevant requirements.
Suspected cases
Those who present with the above clinical manifestations and also have any one of the following epidemiologic histories:
History of traveling outside of the reporting area of monkeypox cases within 21 days prior to the onset of illness;
Close contact with monkeypox cases within 21 days prior to onset of illness;
Contact with blood, body fluids or secretions of monkeypox virus-infected animals within 21 days prior to onset of illness.
Confirmed cases
Suspected cases with positive nucleic acid test for monkeypox virus or culture isolation of monkeypox virus.
Differential Diagnosis
The differential diagnosis usually includes chickenpox, measles, bacterial skin infections, scabies, drug allergies, and syphilis.
Chickenpox
On physical examination, varicella lesions may be found in various stages of development and healing, mostly centripetal in distribution and without lymphadenopathy, whereas monkeypox lesions are usually all in the same stage, mostly centrifugal in distribution.
Measles.
Measles patients are the only source of infection and usually have a history of contact with a measles patient prior to the onset of the disease.
The incubation and prodromal phases of measles may be characterized by low to moderate fever, and in the early stages there may be the characteristic manifestation of oral measles mucous membrane spots, which mainly occur in the buccal mucosa as gravel-sized grayish-white dots surrounded by a red halo, and may spread to the mucous membranes of the lips, gradually disappearing after the appearance of the rash.
There is usually a typical sequence of rashes:
After 3 to 4 days of fever, the rash starts from behind the ear, and gradually develops to the face, trunk, limbs, palms and soles of the feet, the rash is red maculopapular at the beginning, which can be fused into a piece, and normal skin can be seen in between the rashes, and the systemic symptoms can be aggravated.
If the rash is complete after 3 to 4 days and there is no complication such as pneumonia, the body temperature starts to decrease, the rash starts to fade away gradually according to the order of appearance, and the systemic symptoms such as appetite and spirit gradually improve.
Bacterial skin infections
Bacterial skin infections can also appear as acute suppurative infections, with symptoms such as pustules and localized redness, swelling, heat, and pain, and are usually not accompanied by systemic symptoms or have mild systemic symptoms.
Scabies
There is often a history of contact with scabies patients, and the same patients are often found at home or in collective units.
Scabies can also present with papules, papules and pustules, with intense itching, usually without systemic symptoms such as headache and fever.
Drug Allergy
Recent history of drug use and other allergies.
The body rash varies in shape, itching is obvious, the rash can gradually subside after stopping the drug, usually not accompanied by systemic symptoms or systemic symptoms are mild. Severe cases can cause anaphylaxis.
Second-stage syphilis
Stage II syphilis can also present with a generalized syphilis rash.
The typical rash is a diffuse symmetrical maculopapular or papular rash involving the entire trunk and extremities, and pustules may also appear, but the rash is small in diameter. It may be accompanied by systemic symptoms such as fever, headache, malaise, and anorexia.
There is usually a history of high-risk sexual exposure.
Smallpox
Given that smallpox has been eradicated worldwide, it is not usually considered a possibility as a differential diagnosis.
The observation of lymphadenopathy in most unvaccinated patients is a key feature that distinguishes monkeypox from smallpox. Lymphadenopathy can occur in the submandibular, neck, or inguinal region.
Treatment
Mild symptoms do not require specific treatment, and care should be taken to keep the skin clean. Symptomatic management is the mainstay of treatment when symptoms are severe, e.g. use of ibuprofen to reduce fever and topical antibiotic ointment for secondary bacterial infection of the skin. Isolation is recommended until the rash heals.
Symptomatic treatment
Bed rest, nutrition and hydration should be taken care of to maintain water and electrolyte balance.
For patients with fever, physical cooling can be used, and when it exceeds 38.5℃, antipyretic and analgesic drugs can be applied to reduce fever, such as ibuprofen, etc. However, attention should be paid to preventing profuse sweating that may cause hypothermia.
Keep the skin, mouth, eyes and nose clean and moist, do not scratch the skin of the rash area to avoid secondary infection.
Analgesic drugs such as ibuprofen may be given if the pain at the rash site is severe.
Complications
Effective antimicrobial drugs can be given to secondary skin bacterial infections, and the antimicrobial drugs can be adjusted according to the results of culture and drug sensitivity of pathogenic bacteria. Prophylactic application of antibacterial drugs is not recommended.
In the presence of corneal lesions, eye drops and vitamin A can be applied.
Encephalitis needs to be treated with sedation, dehydration to reduce cranial pressure, and airway protection.
Psychotherapy
Patients often have psychological problems such as tension, anxiety, depression, etc. Psychological support and counseling should be strengthened, and appropriate medication should be given to assist treatment when necessary.
Traditional Chinese Medicine (TCM)
It is necessary to carry out diagnosis and treatment. Those with fever can be treated with Sheng Ma Ge Gen Tang, Elevation and Dispersion, Zi Xue San and so on. Those with high fever accompanied by a dense pox rash, sore throat, and multiple swollen lymph nodes can be treated with Qingying Tang, Shengma Tiejia Tang, Xuanbai Chengqi Tang, and so on.
Prognosis
Most recover within 2 to 4 weeks of the onset of the disease, rarely causing death. Erythema or localized darkening of color may occur after the rash recovers, and in severe cases, facial scarring may occur.
Cure
Monkeypox is a self-limiting disease and most have a good prognosis, but some may have a darkening of the color of the rash or even scarring.
Severe cases are common in young children and immunocompromised individuals.
The prognosis is related to the branch of the virus contracted, the degree of exposure to the virus, previous health status and severity of complications.
Hazards
Monkeypox is a zoonotic infectious disease that can cause individual infections and pose a risk to life and health. If it spreads among people, it may cause disease outbreaks and epidemics, which will cause great harm to the society.
The West African branch has a case fatality rate of about 3% and the Congo Basin branch has a case fatality rate of about 10%.
Those who are left with scars may have some impact on their appearance.
Daily
Keep the skin dry, do not scratch or claw the affected area, and wash your hands regularly, especially before and after contact with skin wounds. Monkeypox vaccine is available but is not recommended for people outside of high-risk groups, and the primary means of prevention at this time is still not to come into close contact with sick people and their supplies.
Daily management
Life management
Suspected and confirmed cases should be placed in isolation wards. Suspected cases should be isolated in a single room.
Personal belongings should be used exclusively to avoid cross use with others.
Dietary management
Eat a balanced diet with adequate protein, vitamins, minerals, dietary fiber and water.
Adults should drink 1,500 to 2,000 milliliters of water per day (or control the amount of water according to the doctor’s requirements).
Avoid spicy and stimulating foods, such as raw onions, ginger, garlic and chili peppers.
Prevention
Vaccination
At present, there is no vaccine approved and marketed in China that is specific for monkeypox.
Past data proves that smallpox vaccination can prevent monkeypox with an 85% effective rate, but smallpox vaccine is no longer available for general public use after the global eradication of smallpox. Previous smallpox vaccination may reduce monkeypox disease.
A smallpox/monkeypox vaccine is available, but large-scale safety data are lacking, so it is generally used only for people at high risk in specific situations and is not recommended for the general population.
Reducing exposure to the virus
In the absence of a specific treatment, the best way to minimize infection is to raise awareness of risk factors and understand the steps that need to be taken to reduce exposure to the virus.
Avoid contact with animals that may carry the virus (including animals that are sick or found dead in areas where monkeypox occurs).
Avoid contact with any materials that have come into contact with sick animals, such as clothing and bedding.
Isolate infected patients from others who may be at risk of infection.
Medical personnel need to implement standard precautions by wearing disposable latex gloves, medical protective masks, protective masks or goggles, disposable isolation gowns, etc., as well as proper hand washing and hand sanitizing.
Patients’ secretions, feces and blood contaminants should be strictly disinfected and treated in accordance with the Technical Code for Disinfection in Healthcare Institutions.