A new, potentially more dangerous version of mpox has been found in the U.S.

By Chris MorrisFormer Contributing Writer
Chris MorrisFormer Contributing Writer

    Chris Morris is a former contributing writer at Fortune, covering everything from general business news to the video game and theme park industries.

    A more severe mpox strain has been found in the U.S.
    A more severe mpox strain has been found in the U.S.
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    A new, potentially more dangerous strain of mpox, the virus formerly known as monkeypox, has been reported in California.

    The California Department of Public Health (CDPH) has reported the first known case of clade I mpox. The patient recently traveled to the U.S. from Africa, where the strain is endemic.

    Officials say that, as of now, the risk to the public is low and the patient has not been hospitalized.  

    Clade I is different than the mpox strain that first found its way into the U.S. in 2022. Historically, clade I has been known to result in more severe illnesses than clade II, but the CDPH says recent clade I infections have not been as clinically severe as previous outbreaks.

    Officials said people who were on the plane and in close contact with the patient are being contacted, but likely are not at risk. Current research on this mpox strain indicates it is spread much like clade II, via skin-to-skin and sexual contact.

    Mpox hasn’t been leading the headlines much in the U.S. since the initial 2022 scare, when much of the country was still reeling from the COVID-19 pandemic. But it has stayed on the radar of world health officials. In three days, the World Health Organization (WHO) will convene an emergency committee on mpox to advise the WHO Director-General as to whether mpox continues to constitute a public health emergency of international concern.

    Officials, in the most recent report, estimate there have been nearly 47,000 suspected cases in Africa this year, with almost 14,000 of those coming in the last six weeks. The Congo has been particularly affected.

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