The Dog Days of Summer were a time associated by ancient cultures with disaster and mad dogs. But what if it was more than that? In some cultures, the effects of the star Sirius had a more profound effect on individuals every few hundred years, especially those with specific genes, to trigger canine transformations. Some say this may have been the inspiration for Werewolves.
But this was mostly isolated because of the lack of dissemination of genes. The Black Death likewise decreased the population of those capable of undergoing the transformation, but as the world became more connected, it started to spread again. And this year, the effects are about to take hold again on a larger than normal percentage of humans.
While this will not turn all humans, at least not without special circumstances, the transformation will last as long as the dog days of summer last. However, women who become pregnant during this time cannot transform back. The human mind remains intact, however, the canine instinct remains strong and can overwhelm the human mind.
There are no rules to what they are transformed into, though usually its a species native to where they are from. It can be either wild or domestic as well.