Colombia Confirms First Case of Mpox Clade Ib Variant

Colombian health authorities have confirmed the country’s first case of the Ib subclade of mpox, marking the emergence of a new genetic variant of the virus previously associated with outbreaks in Central and East Africa. The case was identified in a patient from Antioquia department and reported by the Ministry of Health and Social Protection (MinSalud) in mid-April 2026. While officials stress that the risk to the general population remains low, the detection underscores the importance of continued surveillance and awareness of transmission pathways and symptoms.

The Ib subclade belongs to the broader clade I lineage of the monkeypox virus, which has historically been linked to more severe disease compared to clade II variants that drove the global outbreak in 2022–2023. According to the World Health Organization (WHO), clade I infections have been associated with higher fatality rates in endemic regions, particularly among immunocompromised individuals and children. However, the WHO also notes that clinical outcomes depend heavily on access to care, vaccination status and underlying health conditions.

MinSalud confirmed that the patient presented with typical mpox symptoms, including fever, headache, muscle aches, fatigue, and a characteristic rash that progresses through stages—macules, papules, vesicles, pustules, and scabs. Lesions were concentrated on the face, extremities, and genital area, consistent with patterns seen in other mpox cases. The individual sought medical care after noticing skin lesions and was isolated upon diagnosis. Public health teams conducted contact tracing, and no secondary cases have been identified as of the latest update.

Transmission of mpox primarily occurs through close physical contact with infectious lesions, bodily fluids, or contaminated materials such as bedding or clothing. Respiratory droplets can also spread the virus during prolonged face-to-face contact, though this is considered less common than direct skin-to-skin transmission. Health officials emphasize that the virus does not spread easily through casual contact and that brief interactions, such as passing someone in a hallway, pose minimal risk.

In response to the detection, MinSalud reiterated its recommendation for individuals who develop unexplained rashes or symptoms consistent with mpox to seek medical evaluation promptly, especially if they have had recent close contact with someone diagnosed with or suspected of having the virus. The ministry also advised healthcare providers to remain vigilant for atypical presentations and to report suspected cases through national surveillance channels.

Vaccination remains a key tool in preventing severe outcomes. The JYNNEOS vaccine, approved for use against both monkeypox and smallpox, has been shown to provide effective protection against clade I and clade II variants when administered before or shortly after exposure. Colombia has maintained a limited stockpile of the vaccine for high-risk groups, including healthcare workers and individuals with known exposures, though mass vaccination is not currently recommended. The WHO continues to monitor global mpox activity and advises countries to strengthen diagnostic capacity and community engagement, particularly in populations at higher risk of exposure.

While the Ib subclade has not been widely characterized in peer-reviewed literature, genetic sequencing suggests it shares close similarity with strains circulating in the Democratic Republic of the Congo and neighboring countries, where clade I viruses are endemic. Experts caution that further genomic analysis is needed to determine whether this variant exhibits any significant changes in transmissibility, virulence, or immune evasion. To date, there is no evidence that the Ib subclade responds differently to antiviral treatments such as tecovirimat, which remains the primary therapeutic option for severe cases.

Health authorities stress that the confirmation of a single case does not indicate an outbreak or widespread community transmission. Instead, it reflects the effectiveness of Colombia’s disease surveillance system in detecting imported or sporadic cases early. Similar isolated detections have occurred in other non-endemic countries in recent months, often linked to travel or epidemiological connections to regions where clade I mpox is circulating.

As global health bodies continue to monitor the evolution of the monkeypox virus, officials recommend relying on verified information from national public health agencies and international organizations such as the WHO and the U.S. Centers for Disease Control and Prevention (CDC). Misinformation about transmission routes or symptom severity can contribute to unnecessary stigma and hinder public health efforts. Clinicians and the public are encouraged to stay informed through official channels and to avoid drawing conclusions from unverified sources.