The most recognizable sign of mpox (formerly called monkeypox) is a distinctive rash that progresses through several visible stages over two to four weeks. But the rash isn’t always the first thing to appear. Many people develop flu-like symptoms first, including fever, body aches, fatigue, and notably swollen lymph nodes, which can show up anywhere from a few days to three weeks after exposure.
Early Symptoms Before the Rash
The incubation period for mpox, meaning the time between exposure and the first symptoms, ranges from 2 to 21 days. During the 2022 outbreak, it tended to be shorter, closer to 7 to 10 days. The earliest signs are often general and easy to mistake for the flu or another viral illness: fever, chills, headache, muscle aches, and exhaustion.
One early symptom that sets mpox apart from many look-alike conditions is swollen lymph nodes. Your lymph nodes may swell in the neck, armpits, or groin, and they can feel tender or painful. This swelling is a key feature that helps distinguish mpox from chickenpox, herpes, and syphilis, which typically don’t cause it. If you’re noticing swollen glands alongside other symptoms, especially after close contact with someone who has mpox, that combination is worth paying attention to.
How the Rash Develops Stage by Stage
The rash is the hallmark of mpox, and it follows a predictable progression through four main stages. Sometimes the very first lesions appear inside the mouth or on the tongue before anything shows up on the skin.
- Flat spots (macules): The rash starts as flat, discolored areas on the skin. This stage lasts about 1 to 2 days.
- Raised bumps (papules): Those flat spots become raised and firm. This also lasts roughly 1 to 2 days.
- Fluid-filled blisters (vesicles): The bumps fill with clear fluid, looking somewhat like blisters. This stage lasts another 1 to 2 days.
- Pus-filled bumps (pustules): The fluid turns cloudy or opaque. The bumps feel firm and deep-seated, usually round, and they often develop a dimple or depression in the center. This is the longest active stage, lasting about 5 to 7 days.
- Scabbing and healing: Pustules crust over and form scabs that last 7 to 14 days before falling off. New skin forms underneath.
From start to finish, the full cycle from first spot to healed skin typically takes two to four weeks. Lesions can appear on the face, hands, feet, chest, genitals, or around the anus. During recent outbreaks, many cases have involved lesions concentrated in the genital or anal area rather than spread widely across the body.
Atypical Signs You Might Not Expect
Not every mpox case follows the textbook pattern. Some people develop localized symptoms without an obvious widespread rash, which can make the infection harder to recognize.
Rectal pain and inflammation (proctitis) has emerged as a notable atypical presentation, reported in roughly 14 to 33 percent of cases during recent outbreaks. Symptoms include pain during bowel movements, rectal pressure, bloody stools, and itching around the anal area. In some cases, a person may have only a few scattered skin lesions alongside these rectal symptoms, or the rectal symptoms may appear first.
Sore throat and lesions inside the throat or mouth can also occur, sometimes as an early sign before skin lesions develop. Genital lesions may appear in isolation, resembling a sexually transmitted infection like herpes or syphilis. Because of this overlap, testing is important for an accurate diagnosis.
How Mpox Looks Different From Similar Conditions
Several common infections produce rashes that can look like mpox at a glance. The most reliable distinguishing feature is swollen lymph nodes, which are typical with mpox but uncommon with chickenpox, herpes, and syphilis rashes.
Chickenpox lesions tend to appear in waves at different stages simultaneously and are more superficial. Mpox lesions are deeper, firmer to the touch, and generally progress through stages together in a more uniform way. Herpes blisters are usually clustered in one area and tend to recur in the same spot, while mpox lesions are more widely distributed and firm. Syphilis sores are typically painless in the early stage, which is less common with mpox.
The deep-seated, round, firm quality of mpox pustules, especially with that characteristic central dimple, is fairly distinctive once the rash reaches the pustule stage.
Signs in Children
Children generally develop the same symptoms as adults, but the illness can be more severe. Kids under 8 and those with weakened immune systems face a higher risk of complications, including pneumonia, dehydration, secondary bacterial skin infections, and in rare cases, inflammation of the brain (encephalitis). Respiratory symptoms in a child with mpox are a sign of more serious disease.
Eye Involvement
Mpox can affect the eyes, usually when the virus is transferred from a skin lesion to the eye by touching. This can range from mild redness and swelling of the eyelids to more serious problems like corneal ulcers and scarring. Vision changes, eye pain, or increasing redness alongside other mpox symptoms are signs that the eyes may be involved and need prompt evaluation. In rare cases, eye involvement can lead to permanent vision loss.
When You’re Contagious
A person with mpox is considered contagious from the time symptoms begin until every lesion has crusted over, the scabs have fallen off, and fresh skin has formed underneath. Lesions inside the body, including in the mouth, throat, eyes, and genital or anal area, also need to heal completely. This entire process typically takes two to four weeks, though it can vary. Until all skin has fully healed, the virus can still spread through close physical contact.