The reason why ticks are so dangerous to humans and pets is because ticks can attach and feed on humans. The skin where ticks attach to humans can become red and irritated and start to itch and it makes it worse. 

To humans and pets, ticks that transmit diseases to your dog can also transmit many of the same diseases to people. It is important to realize that people do not get these diseases from their dogs. Both people and dogs get the diseases from ticks they come into contact with outdoors. Ticks can be prevented by regular use of tick control products.