Like cats, bats actually spend a lot of time grooming and cleaning themselves and those in their colony. It is important to them that they stay clean and free of parasites.
Like all mammals, bats can carry rabies. Therefore it is important that you never touch a bat if you find it on the ground or somewhere else where you can pick it up. It is not common that they would be on the ground and thus may be sick.
Many stories are a myth but you should be careful.