Is the 'secret weapon' causing Havana syndrome a mosquito killer?

According to a new Canadian government study, a mosquito killer could be the cause of a mysterious disease affecting about 40 US and Canadian diplomats in Cuba.

The incident took place from late 2016 to 2018, prompting the Trump administration to accuse diplomats of being attacked by a secret weapon. The Canadian side refrained from making charges, according to the Guardian.

In 2017, the U.S. cut its embassy staff in Havana, Cuba, to a minimum. Canada recently made similar moves on the grounds that employees are affected by "Havana syndrome".

Diplomats experience cognitive symptoms, from dizziness and blurred vision to memory loss and difficulty concentrating.

To find out, scientists from Dalhousie University and Nova Scotia Health Authority studied Canadian victims and even the brain of a pet dog after their death in Canada.

US Embassy in Havana, Cuba.(Photo: AP).

The results showed that these people lacked cholinesterase , an enzyme necessary for the functioning of the nervous system. Some pesticides work by inhibiting this substance.

During 2016-2018, Cuba also stepped up the spraying of sterilized drugs to prevent the spread of Zika. It was also a time when diplomats had unusual symptoms.

Research shows that embassy staff get infected at the same time with the disinfectant spray in and around their residence. One of the study's authors, Professor Alon Friedman, said that both Canadian and Cuban public authorities were sprayed with pasteurized drugs.

"We conclude that overexposure to cholinesterase inhibitors is the cause of brain injury , " said Professor Friedman, adding that other causes cannot be ruled out.

Mr. Friedman said it was unclear whether Cubans were affected by the drug, but his team was planning to investigate further with the Cuban scientists.

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