According to France-Presse, Carlos Fernandez de Kosio, director of the United States Department of the Cuban Foreign Ministry, said "It is clear that the US government and specifically the Ministry of Foreign Affairs, worked without transparency, indicating that it is hiding something. He is trying to fabricate an incident depends on political manipulation." The comments come after three senior US officials in charge of the case visited Havana.

The Cuban diplomat held talks with US officials, Francisco Palmeiri, Assistant Secretary of State for the Western Hemisphere, William Todd, Assistant Secretary of State for Administrative Affairs, and Michael Ivanov, Assistant Secretary of State for Diplomatic Security. During the meeting with US officials, the Cuban diplomat refused to use the word attacks, since it was "a disgrace, a lack of transparency and political manipulation."

Since the end of 2016, Washington has claimed that 26 US diplomats have been infected with similar symptoms, usually caused by concussions or minor trauma, including headaches, cognitive disorders, dizziness, hearing loss, fatigue and sleepiness. Washington claims that hearing loss, cognitive impairment and sleepiness are apparently caused by attacks whose source is unknown. These incidents were described as "audio attacks."

The State Department said in June that two of its diplomats had been victims of a mysterious "health accident" that had affected 24 other US diplomats in Cuba.