A multi-agency assessment from US intelligence says it is unlikely that a foreign adversary is behind the cases of so-called Havana Syndrome that has stricken American diplomats, defense officials, and spies. Government officials say that the cases appear to have different causes, from environmental factors to undiagnosed illnesses. The World’s Marco Werman interviews Adam Entous, a New York Times reporter who has covered Havana Syndrome for years in multiple publications.