Monkeypox is a rare disease caused by the monkeypox virus, a type of orthopox virus related to variola and vaccinia viruses.
It is typically seen in Central and Western Africa. The natural reservoir is unknown, but is suspected to be rodents. Transmission of monkeypox virus occurs from animals to human through bites, scratches, or direct contact with animal body fluids. Human-to-human transmission is thought to occur primarily through large respiratory droplets and requires prolonged face-to-face contact. It can also occur through direct contact with body fluids or lesion material, or indirect contact through contaminated bedding or clothing.
Symptoms of monkeypox infection start approximately 7-14 days after exposure but can range from 5-21 days. Initial symptoms are typically flu-like including fever, headache, muscle and back aches, lymphadenopathy, chills, and exhaustion.
Within 1-3 days of the prodrome, the patient develops a rash, often beginning on the face then spreading to other parts of the body. Lesions typically begin to develop simultaneously and evolve together. The rash progresses through 4 stages – macular, popular, vesicular, to pustular – before scabbing over and resolving. This process happens over a period of 2-3 weeks.
Notably, in recent cases, the prodrome may or may not occur and lesions may be localized to the genital and perianal area.
Key Characteristics for Identifying Monkeypox
Lesions are well circumscribed, deep seated, and often develop umbilication
Lesions are relatively the same size and same stage of development on a single site of the body
Lymphadenopathy is common, may be generalized or localized, and is typically a distinguishing feature from smallpox
Disseminated rash is centrifugal with more lesions on the extremities and face
Lesions may occur on the palms and soles of the feet, and are often described as painful
Key features of the Rash
A person is contagious from the onset of the enanthem through the scab stage.
The first lesions to develop are on the tongue and in the mouth
1 - 2 days
Following the enanthem, a macular rash appears on the skin, starting on the face and spreading to the arms and legs and then to the hands and feet, including the palms and soles
The rash typically spreads to all parts of the body within 24 hours becoming most concentrated on the face, arms, and legs (centrifugal distribution)
1 - 2 days
By the 3rd day of rash, lesions have progressed from macular (flat) to popular (raised)
1 - 2 days
By the 4th to 5th day, lesions have become vesicular (raised and filled with clear fluid)
5 - 7 days
By the 6th to 7th day, lesions have become pustular (filled with opaque fluid), sharply raised, usually round, and firm to the touch (deep seated)
Lesions will develop a depression in the center (umbilication)
The pustules will remain for approximately 5 to 7 days before beginning to crust
7 - 14 days
By the end of the second week, pustules have crusted and scabbed over
Scabs will remain for about a week before beginning to fall off
For Chicago residents, CDPH approval or notification is not required when submitting specimens to commercial reference laboratories. Public health approval continues to be required when requesting testing through the IDPH laboratory - please complete the CDPH suspect case report form if testing is being request through the public health laboratory: https://redcap.link/reportmpx. Commercial reference laboratories are automatically electronically reporting test results to public health. CDPH will therefore receive results and pursue appropriate contact tracing and other public health follow up. For Chicago residents, healthcare providers do not need to routinely report cases to CDPH - as with all diagnostic testing, it remains the responsibility of the healthcare provider to notify the patient of their result and pursue all relevant clinical assessments and treatment.
In addition to commercial labs, testing through the IDPH laboratory remains available for certain priority situations. Providers who have established monkeypox diagnostic testing with a commercial reference laboratory may still wish to pursue testing through the IDPH laboratory in certain cases, particularly urgent situations based on the clinical picture (e.g. severe disease, lesions in unusual anatomical sites like the eyes, or in a patient being considered for immediate Tecovirimat for any other reason); individual risk (e.g. immunocompromise, pediatric patients, people who are pregnant or breastfeeding); or public health risk (e.g. residents of congregate settings like homeless shelters or jails). To request public health testing, please complete the CDPH suspect case report form: https://redcap.link/reportmpx and indicate why the test is urgent.
For Chicago residents, CDPH approval is not required for commercial laboratory testing, but is still required for testing being requested through the public health laboratory. To request public health testing, please complete the CDPH suspect case report form: https://redcap.link/reportmpx.
A Job Aid is available for monkeypox testing here.
Personnel who collect specimens should use personal protective equipment (PPE) in accordance with recommendations for healthcare settings. The optimal PPE includes : gown, gloves, eye protection (e.g. goggles or a face shield that covers the front and sides of the face) and a NIOSH-approved N95 filtering facepiece or equivalent or a higher-level respirator
Use a sterile nylon, polyester, or Dacron swab with a plastic, or thin aluminum shaft. Flocked swabs or Eswabs are acceptable. Do not submit wooden or other types of swabs, or swabs in collection/tranport media.
Vigorously swab or brush lesion. It is not necessary to de-roof the lesion before swabbing.
Place each specimen in a separate sterile container (e.g. by break off end of applicator of each swab into a 1.5- or 2-mL screw-capped tube with O-ring, or placing in a sterile urine cup, or 15cc/50cc conical tube). Do not add or store in viral or universal transport media.
Sample the same lesion 2 times, then repeat across 1 other location on the body or a lesion with a different appearance. Use a new swab for each specimen. Each specimen should be stored in its own container. Four specimens should be collected (two lesions, each collected twice).
Label each specimen container with:
Medical Record Number
Lesion Location (e.g. right foot, abdomen, left thigh)
Freeze (-20°C or lower) specimens within an hour after collection. If freezing is unavailable, refrigerate at (2–8°C).
Store refrigerated specimens for up to 7 days and frozen specimens for up to 60 days.
If testing is approved, CDPH will provide Requisition Forms, instructions on how to fill them out, and shipping instructions.
Infection Prevention and Control in Healthcare Settings
Standard Precautions should be applied for all patient care, including for patients with suspected monkeypox.
A patient with suspected or confirmed monkeypox infection should be placed in a single-person room with a dedicated bathroom. The door should be kept closed if safe to do so.
Special air handling is not required unless performing an aerosol-generating procedure (e.g., intubation), in which case an airborne infection isolation room should be used.
Transport and movement of the patient outside of the room should be limited to medically essential purposes. If the patient is transported outside of their room, they should use well-fitting source control (e.g., medical mask) and have any exposed skin lesions covered with a sheet or gown.
PPE used by healthcare personnel who enter the patient’s room should include a gown, gloves, eye protection (i.e., goggles or a face shield that covers the front and sides of the face), and a NIOSH-approved N95 or equivalent respirator.
Patient waste can be managed as Regulated Medical Waste.
Exception: If the patient traveled to Central Africa within the prior 21 days, waste should be managed as a Category A infectious substance.
Standard cleaning and disinfection procedures should be performed using an EPA-registered hospital-grade disinfectant on List Q.
Soiled laundry (e.g., bedding, towels, personal clothing) should be gently and promptly contained in an appropriate laundry bag and never be shaken or handled in a way that may disperse infectious material. Care should be taken to avoid contact with lesion material that may be present on the laundry.
Activities that could resuspend dried materials from lesions (e.g., use of portable fans, dry dusting, sweeping, and vacuuming) should be avoided.
Visitors to patients with monkeypox should be limited to those essential for the patient’s care and wellbeing (e.g., parents of a child or spouse).
Infection Prevention and Control in Home Settings
As much as possible, do not leave the home. Avoid crowds and congregate settings.
If a person with monkeypox is symptomatic with a fever or any respiratory symptoms (e.g., sore throat, nasal congestion, cough), they should remain home unless it is necessary to seek medical care or for an emergency. If leaving the home for medical care or an emergency, the individual should avoid public transportation.
Avoid close physical contact, including sexual and/or intimate contact, with other people.
Limit contact with household members who are not ill.
It is particularly important to avoid close prolonged contact with young children, pregnant women, and immunosuppressed people as they may be at higher risk for serious illness.
Isolate in a room separate from other household members if experiencing respiratory symptoms or extensive sores that cannot be covered.
If possible, use a separate bathroom from other household members.
When in close contact with others, wear a well-fitting mask to prevent the spread of oral and respiratory secretions. Masks should fit closely on the face without any gaps along the edges or around the nose and be comfortable when worn properly over the nose and mouth.
If it is not feasible for the person with monkeypox to wear a mask, other household members should wear a well-fitting mask when in close contact (i.e., within 6 feet) for more than a brief encounter with the person who has monkeypox.
Avoid contact with pets and other animals.
Cover all parts of the rash/lesions with clothing, gloves, and/or bandages.
Do not share potentially contaminated items, such as bedding, clothing, towels, drinking glasses, or eating utensils with other people or animals.
Launder or disinfect items and surfaces before use by others.
Laundry may be washed in a standard washing machine with warm water and detergent. Do not shake soiled laundry.
For disinfection of items and surfaces, use an EPA-registered disinfectant product (see List Q) in accordance with the manufacturer’s instructions.
Wash hands often with soap and water or use an alcohol-based hand sanitizer, especially after direct contact with the rash.
Restrict visitors to those who are essential to being in the home, especially if they have not been previously exposed.
Avoid use of contact lenses to prevent inadvertent infection of the eye.
Avoid shaving rash-covered areas of the body, as this can lead to spread of the virus.
After ending isolation, use safe sex and barrier practices (e.g., wearing condoms) for at least 8 weeks.
Isolation and De-Isolation
Current data suggest that people can spread monkeypox from the time symptoms start until all symptoms have resolved, including full healing of the rash with formation of a fresh layer of skin.
Ideally, people with monkeypox should remain in isolation at home or in another location for the duration of illness (typically two to four weeks), but that may not be possible in all situations.
Prioritizing isolation and source control strategies helps prevent transmission while balancing the impact of this infection on the daily lives of people diagnosed with monkeypox.
If a person with monkeypox is unable to remain fully isolated throughout the illness, they should do the following:
While symptomatic with a fever or any respiratory symptoms, including sore throat, nasal congestion, or cough, remain isolated in the home and away from others unless it is necessary to see a healthcare provider or for an emergency.
This includes avoiding close or physical contact with other people and animals.
Cover the lesions, wear a well-fitting mask (more information below), and avoid public transportation when leaving the home as required for medical care or an emergency.
When a rash persists but in the absence of a fever or respiratory symptoms:
Cover all parts of the rash with clothing, gloves, and/or bandages.
Wear a well-fitting mask to prevent the wearer from spreading oral and respiratory secretions when interacting with others until the rash and all other symptoms have resolved.
Masks should fit closely on the face without any gaps along the edges or around the nose and be comfortable when worn properly over the nose and mouth.
Until all signs and symptoms of monkeypox illness have fully resolved:
Do not share items that have been worn or handled with other people or animals. Launder or disinfect items that have been worn or handled and surfaces that have been touched by a lesion.
Avoid close physical contact, including sexual and/or close intimate contact, with other people.
Avoid sharing utensils and cups. Items should be cleaned and disinfected before use by others.
Avoid crowds and congregate settings.
Wash hands often with soap and water or use an alcohol-based hand sanitizer, especially after direct contact with the rash.
Decisions regarding discontinuation of isolation precautions should be made in consultation with the individual’s provider. For individuals with monkeypox, isolation precautions in home settings should be continued until all lesions have resolved, the scabs have fallen off, and a fresh layer of intact skin has formed. If someone is unable to isolate, it is important to avoid close contact with young children, pregnant women, and immunosuppressed people as they may be at higher risk of severe illness.
People with immunocompromising conditions (e.g., HIV/AIDS, leukemia, lymphoma, generalized malignancy, solid organ transplantation, therapy with alkylating agents, antimetabolites, radiation, tumor necrosis factor inhibitors, high-dose corticosteroids, being a recipient with hematopoietic stem cell transplant <24 months post-transplant or ≥24 months but with graft-versus-host disease or disease relapse, or having autoimmune disease with immunodeficiency as a clinical component).
Interim guidance for treatment of monkeypox including supportive care and other therapeutic options is available here.
Supportive care includes maintaining hydration and pain management. Other recommendations may include:
Skin lesions should be kept clean and dry when not showering or bathing to prevent a secondary bacterial infection.
Itching can be managed with oral antihistamines (such as diphenhydramine [Benadryl®], cetirizine, hydroxyzine) or topical anti-irritant agents such as calamine lotion or petroleum jelly (Vaseline).
For oral lesions, your doctor may prescribe compounds such “magic” or “miracle” mouthwashes (prescription solutions used to treat mucositis) to manage pain. Oral antiseptics can be used to keep lesions clean (e.g., chlorhexidine mouthwash). Topical benzocaine/lidocaine gels (for example, Orajel®) can be used for temporary relief, especially to facilitate eating and drinking, but should be limited to recommended doses.
For painful genital and anorectal lesions, warm sitz baths lasting at least 10 minutes several times per day may be helpful. Topical benzocaine/lidocaine gels or creams (for example RectiCare®) at the recommended doses may also provide temporary relief. Patients with blood in their urine or who are unable to urinate as well as those with phimosis (inability to retract foreskin) or paraphimosis (retracted foreskin cannot return to it’s natural position) should be evaluated by a healthcare provider.
Proctitis (infection and inflammation of the lining of the rectum, internal to the anus) can occur with or without internal lesions. It can cause rectal bleeding and mucus in stools; diarrhea; a feeling of fullness in your rectum; urgency and a sensation of needing to pass a bowel movement without being able to; as well as pain with bowel movements. Stool softeners such as docusate (Colace®) should be initiated early. Sitz baths are also useful for proctitis, and may calm inflammation. Similarly, over the counter pain medications such as acetaminophen can be used. Pain from monkeypox proctitis may require prescription medications, use of which should be balanced with the possibility of side effects, like constipation. Proctitis may additionally be accompanied by rectal bleeding. Though rectal bleeding has been observed to be self-limited, patients with rectal bleeding should be evaluated by a healthcare provider. Patients who are unable to pass a bowel movement should also be evaluated by a healthcare provider.
Nausea and vomiting may be controlled with anti-emetics as appropriate and prescribed by a healthcare provider.
Diarrhea should be managed with appropriate hydration and electrolyte replacement. The use of anti-motility agents (e.g. loperamide [Imodium®]) is not recommended given the potential for ileus.
Treatment of superimposed bacterial skin infections and treatment of co-occurring sexually transmitted infections (e.g Gonorrhea, Chlamydia, syphilis, HIV) is important for healing and can help with complicated symptoms.
The antiviral Tecovirimat is available under investigational new drug (IND) protocol and should be considered for individuals meeting the following criteria:
Severe disease (e.g., hemorrhagic disease, confluent lesions, sepsis, encephalitis, or other conditions requiring hospitalization)
Those at high risk of severe disease:
Immunocompromised, including those with poorly controlled HIV
Pediatric populations, especially those <8 years old
Pregnant or breastfeeding women
Individuals with one or more complications (e.g., secondary bacterial skin infections; gastroenteritis with severe nausea/vomiting, diarrhea, or dehydration; broncho pneumonia, concurrent disease or other comorbidities)
Individuals with monkeypox infections that include mucosa (genitals, anus), or accidental implantation in the eyes or mouth.
Post Exposure Prophylaxis And Extended Post Exposure Prophylaxis
Post exposure prophylaxis (PEP) with the Jynneos vaccine is available for individuals who have had “high” or “intermediate” close contact with a confirmed case of monkeypox (MPV). PEP should ideally be provided within 4 days from the date of last exposure to prevent onset of disease. If given between 4-14 days after the date of exposure, vaccination may reduce the symptoms of disease, but may not prevent the disease. Providers treating suspect cases are encouraged to discuss with patients that CDPH will be reaching out to identify close community contacts and that patients should be prepared to give this information to a public health representative so that these contacts can be assessed for PEP.
Considerations for Expanded Post-Exposure Prophylaxis (PEP)
Prioritize JYNNEOS vaccine administration to:
Individuals who had close physical contact with someone diagnosed with MPV, or those who know their sexual partner was diagnosed with MPV in the last 14 days,
Gay, bisexual or other (cis or trans) men who have sex with men and/or transgender, gender non-conforming, or gender non-binary (GBMSM) who meet at least 1 of the following risk criteria:
Have had intimate or sexual contact with other (cis or trans) men in a social and/or sexual venue in Chicago in the last 14 days,
Have had intimate or sexual contact with multiple (two or more) or anonymous intimate partners in the last 14 days in Chicago,
Have given or received money or other goods/services in exchange for sex in Chicago in the last 14 days.
Monkeypox virus testing is now available at many commercial reference laboratories, including LabCorp & Quest. Specimen can be submitted directly to commercial laboratories without prior CDPH approval.
Lab testing at the IDPH Laboratories with select criteria only. Prior approval for testing at requested through the public health laboratory. To request public health testing, please complete the CDPH suspect case report form: https://redcap.link/reportmpx.
Criteria for testing at IDPH Laboratories are as follows:
Urgent test based on clinical picture, including but not limited to:
severe disease (e.g. hemorrhagic disease, confluent lesions, sepsis, encephalitis, or other conditions requiring hospitalization)
individuals with likely monkeypox infections in unusual anatomical sites (e.g. eyes or mouth)
individuals being considered for Tecovirimat, imminently for any other clinical reason
Urgent test based on individual risk:
those at risk of severe disease (e.g., immunocompromised, pediatric populations especially <8 years, pregnant or breastfeeding women, individuals with one or more complications)
inability to be tested elsewhere due to expense of testing
Urgent test based on epidemiological risk:
possible outbreaks of public health concern requiring especially prompt follow-up action, e.g., in congregate living settings (jails, homeless shelters, skilled nursing facilities, schools)
other situation deemed by the local health department as warranting testing at the state lab
Outside of business hours (after 5pm through before 8am, and on City holidays), collect specimens, and approval will be provided during normal business hours.
If you have a need for urgent public health guidance, please call 311 (or 312-744-5000 if outside the City of Chicago) and ask for the CDPH medical director on call.