It is claimed that only Borrelia Burgdorferi causes Lyme disease in North America, and only Borrelia Afzelii and Borrelia Garinii can cause Lyme disease in Europe. But there are 36 known types of Borrelia, and some claim that 12 of them are known to cause disease in humans. Do these all cause the same disease, with the same symptoms? Where are they located? If human studies are lacking in regions, animal studies might be more productive. There seems to be less of a reluctance to look for various types of Borrelia in dogs and cattle.