Mpox Cases Rise in Brazil: Symptoms, Spread, and Prevention

Brazil is experiencing an increase in mpox (formerly known as monkeypox) cases, with 129 confirmed infections reported nationwide as of March 5, 2026, according to the Ministry of Health. Even as not currently classified as a crisis, health officials are closely monitoring the situation, particularly following increased social interaction during Carnival.

Current Situation and Case Numbers

As of March 5, 2026, Brazil has reported 129 confirmed mpox cases. São Paulo is a significant hotspot, accounting for 86 cases, or 66% of the national total. Other states reporting cases include Rio de Janeiro (18), Rondônia (11), Minas Gerais (11), Rio Grande do Norte (3), Rio Grande do Sul (3), Santa Catarina (3), Paraná (2), Amazonas (1), Ceará (1), Distrito Federal (1), Pará (1), and Sergipe (1). Currently, 570 cases are under investigation, with 7 classified as probable.

In February 2026, the state of São Paulo had already confirmed 44 cases of mpox. Since 2022, São Paulo has recorded over 6,000 confirmed cases and three deaths related to mpox.

What is Mpox?

Mpox is an infection caused by the mpox virus, which is related to the smallpox virus. The virus is divided into two clades, 1 and 2, further divided into subclades 1a, 1b, 2a, and 2b. Clade 1a is typically found in Central African countries, while clade 2b was first detected in Nigeria. Symptoms caused by clade 1b tend to be more severe, particularly in individuals with weakened immune systems.

Symptoms of Mpox

Initial symptoms of mpox include fever, headache, body aches, fatigue, and swollen lymph nodes. If the infection progresses, skin lesions can appear on the face, genital region, perianal region, palms of the hands, feet, and mucous membranes (eyes, mouth, and nose). Serious cases can lead to neurological and ocular complications.

How Mpox Spreads

Mpox primarily spreads through direct, skin-to-skin contact with someone who has an active rash. This includes contact with skin lesions and potentially through mucous membranes. Transmission can occur even before symptoms appear or from asymptomatic individuals. While less common, transmission through respiratory droplets and contaminated objects is also possible. Sexual transmission is possible, particularly among men who have sex with men, but the risk is not limited to this group.

Prevention and Vaccination

The most important preventative measure is avoiding skin-to-skin contact with individuals who have mpox. Individuals with symptoms should isolate themselves during the period when lesions are active.

The Ministry of Health has acquired vaccines for individuals at higher risk, including people living with HIV/AIDS with low CD4 cell counts (100-200 cells), PrEP users, and healthcare professionals handling virus samples. However, vaccine supplies have been insufficient to meet the demand.

Other preventative measures include practicing good hygiene, frequent handwashing, and seeking medical evaluation and isolation if symptoms develop or after close contact with a suspected or confirmed case.

Recent Developments: Clade 1b and Recombinant Strain

In São Paulo, two cases identified in January 2026 belonged to clade 1b, a subvariant historically associated with more severe illness. The World Health Organization (WHO) has also detected a new recombinant strain of clades 1b and 2b in India and the United Kingdom. While these cases presented with symptoms similar to other clades without severe progression, the WHO maintains a moderate risk assessment for groups with greater exposure and a low risk for the general population.

Looking Ahead

Brazil recorded 1,079 cases and two fatalities in 2025. Continued surveillance, vaccination efforts, and public health awareness are crucial to managing the current uptick in mpox cases and preventing a larger outbreak.