“Acoustic attack” in Cuba could be related to an insecticide destined to fight Zika, according to a study

• Click to share on Facebook (Opens in a new window)
• Click to share on Twitter (Opens in a new window)
• Click here to share on LinkedIn (Opens in a new window)
• Click to email a friend (Opens in a new window)

(CNN) - A mysterious disease that affected dozens of US and Canadian diplomats in 2016 in Havana, Cuba, is probably related to insecticides sprayed to fight the Zika virus, according to a new study by a team of scientists in Canada.

Government personnel complained of symptoms such as dizziness, ringing in the ears, pain, blurred vision, dizziness and problems with memory and concentration. The leaders of the United States Department of State were concerned that the staff were victims of an "acoustic attack" by sonic devices. The mysterious disease became known as "Havana syndrome".

• Microwave weapons are the main suspects in the 'acoustic attacks' on US diplomats. in Cuba and China, say scientists

Diplomats have been studied by federal agencies and government scientists. They have been at the center of a Senate hearing and investigation. The Cuban government denied any participation in the incidents. The president of the United States, Donald Trump, said in 2017 that he believed that Cubans were “responsible” for diplomats to get sick. In March 2018, the State Department announced that it would keep the staff of its embassy in Cuba at the minimum level required to perform “central diplomatic and consular functions” due to concerns about the “health attacks” of the staff.

Tests conducted on 26 Canadian diplomats in the period from August 2018 to February 2019 increased the possibility of “overexposure to cholinesterase inhibitors,” possibly through insecticides. Cholinesterase is an enzyme necessary for the proper functioning of the nervous system.

"While the source of exposure to the toxins of the cholinesterase inhibitor family has not yet been confirmed in our study, the use of insecticides is suggested in an easy and obvious way," says the study. “It is important to note that certain chemical classes of pesticides, such as organophosphates and carbamates, work against insects by inhibiting the action of cholinesterase, but they can also be poisonous to humans.

The research was funded by Global Affairs Canada and has not yet been published, but it is undergoing the peer review process. The researchers shared the study with CNN.

The tests included cognitive assessments, symptom questionnaires, blood tests, brain imaging and medical history. When 24 of the original test subjects were reexamined 200 days later, doctors said there were "cognitive, vestibular and oculomotor abnormalities that suggested a 'sustained injury to generalized brain networks,'" according to the study.

Mass spectrometry tests confirmed the presence of cholinesterase inhibitor insecticides, including Temephos, an organophosphorus used in Cuba to fight mosquitoes. The tests also found 3-phenoxybenzoic acid, a common insecticidal metabolite.

Temefos was found in 6 of the 10 individuals exposed remotely, compared to a recently exposed individual, and did not appear in any of the patients who were not exposed. (Those considered “exposed remotely” were those evaluated between one and 19 months after returning. “Recently exposed persons were evaluated within one month of their return”). 3-Phenoxybenzoic acid was found in most of the exposed people who were tested.

The United States Environmental Protection Agency canceled the use of Temephos in the country in 2011, but the chemical is still used in Cuba and in some other nations.

The researchers wrote that, at the time, Cuba had well-documented efforts underway to stop the spread of the Zika virus, including massive indoor and outdoor spraying. The embassy records also confirmed an increase in the number of times people sprayed mosquitoes in the Canadian office and in staff houses in January 2017, which coincided with the time people reported symptoms.

Zika virus disease is a disease that is transmitted through mosquito bites. It can cause birth defects and other neurological problems. After the outbreaks began in 2015, the Centers for Disease Control and Prevention (CDC) activated its emergency response to Zika in January 2016 and deactivated it in September 2017.

A call to the US Department of State was not returned. About the study

One of the study's authors said that this is only the beginning of the research, but he hopes that what they learn can help protect public health.

"It took us many months to reach this conclusion and there is still a lot of research to do, but we believe that this is the beginning of a response to what happened," said study co-author Dr. Alon Friedman, a professor of neuroscience and the Dennis Chair in Epilepsy Research in the departments of medical neuroscience and pediatrics at Dalhousie University in Halifax, Nova Scotia.

Friedman said the researchers hope to work with Cuban scientists to see if other individuals in the area were affected.

"There are many things we don't know about how much we can expose people to these chemicals and what the toxic levels are or if the damage to the brain is reversible," Friedman said. “But it's not called neurotoxin for nothing. The clue is in the name. ”

acoustic attacks