LULU GARCIA-NAVARRO, HOST:
U.S.-Cuba ties are strained over a medical mystery. And some Cuban doctors came to Washington this past week hoping to turn the page. But they say they still don't have much information about what the U.S. is calling health attacks on American personnel based in Havana. NPR's Michele Kelemen reports.
MICHELE KELEMEN, BYLINE: A Cuban medical team left a meeting at the State Department Thursday night sounding frustrated by what they see are the constantly changing U.S. theories about what or who caused health problems for 26 Americans serving in Cuba.
MITCHELL VALDES-SOSA: We really didn't receive much information. But we don't feel we came for nothing.
KELEMEN: That's Dr. Mitchell Valdes-Sosa, who led the group of Cuban experts on a long-awaited trip to Washington. The visit came as NBC News was reporting on the latest theory that Russia was behind the attacks in Cuba that caused a range of symptoms starting in 2016 from dizziness to hearing loss and minor brain trauma. But Valdes-Sosa says the idea that there's some sort of sonic or a microwave weapon that can do that is not backed up by science.
VALDES-SOSA: Everything that has appeared as a hypothesis isn't plausible. So before we start searching for a James Bond kind of thing, trying to find who is the person that's attacking, we have to demonstrate that there was brain damage and that the mechanism is plausible.
KELEMEN: Valdes-Sosa was hoping to meet the University of Pennsylvania doctors who examined the Americans. But he came away from his meetings with State Department doctors and officials with no more details than what was already presented in a medical journal article.
VALDES-SOSA: We expressed our reservations and our criticism of the paper. And we received no response. Essentially, our impression is - and the doctors were very frank. They don't know what's happening.
KELEMEN: At the State Department, spokesperson Heather Nauert remains tight-lipped about the investigation and told reporters to be skeptical of the unnamed officials who suggest Russia is behind this.
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HEATHER NAUERT: We still don't know the cause. We still don't know what or who is responsible for health attacks that took place that affected our personnel in Cuba.
KELEMEN: The Cuban foreign ministry official who traveled with the doctors says the State Department should stop calling them attacks, arguing that the U.S. has been treating theories as facts and changing its theories every week. Michele Kelemen, NPR News, the State Department.
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