Despite the fact that bites are incredibly rare, the Australian Copperheads are 50 times more venomous then their American namesakes and are not actually closely related at all!
Australian copperheads are in the elapid family, making them closer to things like cobras, the black mamba, and all the famous Australian venomous snakes like the tiger snake and brown snake. American copperheads on the other hand are members of the viper family, along with rattlesnakes, bushmasters and adders.
Here in Australia we have three species of copperheads, the lowlands copperhead, the alpine copperhead and the Pygmy copperhead, who between them occupy the cooler climates of eastern NSW, coastal Victoria, South Australia and Tasmania
Being cold climate snakes copperheads give birth to live young rather then laying eggs, due to the fact the climate in which they are found often isn’t suitable for incubation of eggs
While being more then 50 times as venomous as the American copperhead, and roughly equivalent in toxicity to the Indian cobra, which kills more then 10,000 people a year, bites from Australian copperheads are incredibly rare, and deaths are almost unheard of. Interestingly, there’s actually no such thing as copperhead antivenin, with copperhead bites in Australia being treated with tiger snake anti venom