It is my opinion that deer are the main carriers of Lyme disease because they come into direct contact with tics that carry the disease on a daily basis. Tics often find their homes in the hide of deer, and many tics carry the disease. This would make deer much more likely than other animals to be carriers of lyme disease.
Even though many types of animals carry lyme disease deer seem to carry more then any other species of animal so I would say that deer are indeed on the main carriers of lyme disease, I think more research and treatment should be focused on reducing the amount of lyme disease.
While deers carry the disease, they are not the main carriers of Lyme disease. There are a lot of animals in the forest that carry the disease. But I think that there are more smaller creatures that carry the disease. And the biggest problem concerning Lyme disease are things like ticks.
While deer may be blamed for Lyme disease, it's actually carried and transmitted through ticks, which live on animals. So deer are the hosts, until and unless the ticks choose to transfer to another species, such as a human. Ticks get the disease from rodents, and then live on the deer as hosts. So deer are really more of a host, and not the cause of Lyme disease.
The main carriers of Lyme disease are the ticks that give the lyme to deer. Deer may be the ones who get it the most often, but they are definitely not the main carries of it. The disgusting parasites that spread the disease around are the main carriers, by a long shot.