A new study commissioned by the Canadian government concluded that fumigation against mosquitoes in Cuba and not “sonic attacks” may have caused about 40 U.S. and Canadian diplomats and family members in Havana to fall ill.
The researchers for this study said that they had detected different levels of brain damage in an area responsible for memory, concentration and sleep-and-wake cycle and that “there are very specific types of toxins that affect these kinds of nervous systems … and these are insecticides, pesticides, organophosphates — specific neurotoxins.” They then concluded that cholinesterase, a key enzyme required for the proper functioning of the nervous system, was being blocked there.
Some pesticides work by inhibiting that enzyme, the report said, and during the 2016-2018 period when diplomats became ill, normal fumigation in Cuba was stepped up due to the Zika epidemic in the Caribbean. That increased fumigation in and around residences where they lived in Cuba was conducted by both Cuban and Canadian authorities.
The Canadian (and U.S.?) embassies actively sprayed in offices, as well as inside and outside diplomatic residences — sometimes five times more frequently than usual. Many times, spraying operations were carried out every two weeks, according to [Canadian?] embassy records. Toxicological analysis of the Canadian victims confirmed the presence of pyrethroid and organophosphate — two compounds found in fumigation products. There also was a correlation between the individuals most affected by the symptoms and the number of fumigations that were performed at their residence.
The Canadian researchers will now collaborate with Cuban officials to determine whether any Cubans suffered similar brain injuries.
The Canadian study was conducted by a team of researchers affiliated with the Brain Repair Centre at Dalhousie University and the Nova Scotia Health Authority. In charge was Dr. Alon Friedman, from the Department of Neurosciences and Medical Pediatrics, Dalhousie University, Canada.
Cuban experts consider that the hypothesis presented by the Canadian team is a serious attempt to explain the symptoms reported through scientific research, “although it is premature to reach conclusions,” says Doctor of Science Mitchell Joseph Valdés-Sosa, General director of the Neurosciences Center of Cuba.
So far no U.S. reactions to this study have been found.
 Friedman, Calkin & Bowen, Havana Syndrome: Neuroanatomical and Neurofunctional Assessment in Acquired Brain Injury Due to Unknown Etiology (May 24, 2019); Reuters, Exposure to neurotoxin may have caused Canadian, U.S. diplomats’ ailments in Cuba, Globe & Mail (Sept. 19, 2019); Havana syndrome: Exposure to neurotoxin may have been cause, CBS News (Sept. 19, 2019); Confirmed: “There is no Havana syndrome caused by mysterious weapons,” Cubadebate (Sept. 16, 2019); Cuban authorities endorse the new theory on the health conditions of diplomats, Diario de Cuba (Sept. 20, 2019). The medical problems of U.S. and Canadian diplomats in Cuba have been discussed in many posts in this blog. (See “U.S. Diplomats Medical Problems in Cuba, 2017-18” and “U.S. Diplomats Medical Problems in Cuba, 2019” sections in List of Posts to dwkcommentaries—Topical: CUBA.