Mpox, monkeypox virus, orthopoxvirus, rash, lesions, close contact, clades, testing, isolation, tecovirimat, JYNNEOS vaccine, and outbreak response

Mpox

Mpox is an infectious disease caused by monkeypox virus that can produce fever, swollen lymph nodes, and a painful rash or lesions, and it spreads mainly through close contact.

Cause
Mpox is caused by monkeypox virus, an orthopoxvirus related to the viruses used in smallpox vaccines.
Spread
Person-to-person spread usually happens through close contact with lesions, body fluids, respiratory secretions, or contaminated materials.
Name
Mpox is the preferred disease name; it was previously called monkeypox.
Mpox virus is an orthopoxvirus that can spread through close contact and cause a rash or lesions.View image on Wikimedia Commons

What mpox is

Mpox is a viral illness caused by monkeypox virus. It is part of the orthopoxvirus family, which also includes variola virus, the cause of smallpox. Mpox is usually less severe than smallpox, but it can still cause painful lesions, complications, severe disease, and outbreaks that require public-health response.

How it spreads

Mpox spreads through close, often skin-to-skin contact with someone who has mpox. Contact with rash lesions, scabs, body fluids, respiratory secretions during close face-to-face contact, or contaminated items such as bedding can transmit the virus. In some settings, animal-to-human transmission can occur through contact with infected animals.

Symptoms

Symptoms can include fever, chills, swollen lymph nodes, exhaustion, muscle aches, headache, sore throat, and a rash or lesions. The rash can appear on the face, hands, feet, chest, genitals, anus, mouth, or other areas. Lesions may be painful or itchy and usually move through stages before scabbing and healing.

Clades and outbreaks

Monkeypox virus has multiple clades, or genetic groups. Clade II drove the multi-country outbreak that began in 2022, while clade I outbreaks in Central and East Africa have raised concern because some clade I viruses have been associated with more severe disease. Public-health guidance can change as clades, transmission patterns, and outbreak locations change.

Diagnosis and testing

Clinicians consider symptoms, exposure history, travel, sexual contact, and local outbreak information. Testing usually involves swabbing lesions for laboratory detection of orthopoxvirus or monkeypox virus DNA. Because mpox can resemble chickenpox, herpes, syphilis, allergic rashes, and bacterial skin infections, testing and clinical context matter.

Care and treatment

Many people recover with supportive care, including pain control, skin care, hydration, and prevention of secondary bacterial infection. People with severe disease, eye involvement, complications, pregnancy, young age, or weakened immune systems may need specialized care. Antiviral medicines such as tecovirimat may be considered in selected situations under current guidance.

Vaccination

Vaccination can help prevent mpox before exposure or reduce risk after a known exposure when given soon enough. JYNNEOS is used in several countries for people at higher risk and for outbreak response. Vaccine guidance depends on local supply, eligibility, exposure risk, health status, and the clade or outbreak context.

Isolation and stigma

People with mpox are usually advised to avoid close contact with others until lesions heal, scabs fall off, and a new layer of skin forms. Good guidance also avoids stigma: viruses exploit contact networks and access gaps, not identities. Stigmatizing people can delay care, testing, vaccination, and honest risk communication.

Why it matters

Mpox sits at the crossroads of zoonotic disease, sexual health, vaccination, laboratory capacity, and global equity. Outbreaks can grow when diagnosis is delayed or vaccines and treatment are unevenly available. Clear, non-stigmatizing public-health work helps people reduce risk without driving infections underground.

What public health teams watch

Surveillance tracks cases, clades, travel links, transmission settings, vaccine uptake, severe outcomes, laboratory capacity, and access to clinical care. Teams also monitor whether messages reach affected communities, whether contacts can be notified, and whether outbreak response avoids discrimination.