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Chester Zoo, alongside scientists from the University of Surrey, embarked on the world's first trial of a potentially life-saving vaccine to help Asian Elephants combat the deadly disease, elephant endotheliotrophic herpes virus (EEHV).
Within the first half of the video, someone could be seen conducting lab work for the vaccine.
The vets at Chester routinely test the elephants, so they get used to health examinations and providing blood samples.
In the second half of the video, Aung Bo, a male Asian Elephant, can be seen.
According to the BBC, he was co-operative in the study's trial.
Elephant keeper Katie Morrison told the outlet that it's "based around a positivity and food rewards" system.
"We encourage them to interact with us. But if they don't want to, that's fine. We'll leave them to it and try later."
Morrison further told the outlet that they've "lost elephants usually between the ages of 18 months and three years. "
"When we see symptoms - lethargy, mouth lesions - it's usually too late."
Information about how the virus causes severe disease is unclear.
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