@gemiwing – It isn’t syphilis. The koalas are having a rise in chlamydia infections.
Also, while we don’t typically think of it as an STD, brucellosis, aka undulant fever, is indeed a sexually transmitted disease common among domestic livestock and in other mammals including dogs, goats, deer, and rats. Farmers and vets watch for it carefully because it impacts the birth of offspring, and it can be transmitted to people through infected milk.
BTW, scientists think that syphilis and gonorhea both originated in cattle and possibly sheep, and HIV originated in chimpanzees.
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