A MARTÍNEZ, HOST:
Health officials in Southern California are worried a new strain of the virus mpox is spreading in the U.S. That strain fueled outbreaks in parts of Africa over the past year, and now there are three cases of it in California not linked to overseas travel. Here's NPR's Will Stone.
WILL STONE, BYLINE: This strain of mpox is known as clade I. It's genetically distinct from the version that triggered an outbreak across the U.S. in 2022. These three cases are the first in the U.S. not connected to overseas travel, and there doesn't appear to be any link between the patients either.
SONALI KULKARNI: Which suggests that there may be transmission going on in the community.
STONE: Sonali Kulkarni is medical director of the HIV and STD program at the LA County Department of Public Health.
KULKARNI: That raises our concern because while we don't know a lot about clade I, there is evidence to support that it may be more serious.
STONE: All three patients were hospitalized and are now recovering, though Kulkarni says it's unclear that clade I is the reason for these more severe cases or whether there were other complicating factors.
KULKARNI: Sometimes with detection of diseases, you know, we really find out about the sickest cases first. Now, there may be people who have milder forms who aren't getting even tested.
STONE: The other strain of mpox has circulated at low levels in the U.S. for the past few years, primarily through sexual contact and mostly among gay and bisexual men. Kulkarni says these three new cases of clade I mpox fit that same profile. Anne Rimoin, an mpox researcher at the UCLA Fielding School of Public Health, says, It's true this strain has been associated with more severe cases and higher mortality.
ANNE RIMOIN: Although when we see this, it's been particularly in low-resource settings, like in Central Africa, where I've been working for the last two decades.
STONE: That may not be the case in the U.S., where patients have access to better treatment and care.
RIMOIN: But this certainly is an important moment to understand that there are cases of a potentially more severe clade circulating, and it's not just a heads-up for Southern California. It's a heads-up nationally.
STONE: Dr. John Brooks was the chief medical officer for the CDC's HIV division and retired last year. He says, luckily, the two-dose mpox vaccine or prior infection with the other strain still protect against a severe case.
JOHN BROOKS: There's no evidence at this time that's worrisome for a sudden resurgence of mpox in the United States.
STONE: But Brooks says the U.S. would be in a better place to respond if more of the CDC workers who handle outbreaks were on the job, not furloughed or fired.
Will Stone, NPR News. Transcript provided by NPR, Copyright NPR.
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