It is thought that as much as 88 percent of the antelope from the Betpak-dala desert of Kazakhstan succumbed, accounting for roughly 70 percent of the entire global population of the already endangered antelope.

Now, after continued analysis of samples taken from the carcasses of the saiga, multiple laboratories have come to the same conclusion and identified the bacterium Pasteurella multocida as the cause. It is thought that the bacteria, which naturally lives in the respiratory tract of the animals and normally has no impact on their health somehow became deadly, leading to haemorrhagic septicaemia.

The symptoms of the condition include a high fever, salivation, and shortness of breath, followed by death within 24 hours. This is consistent with what was observed in the field.

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