Ticks can carry several types of bacteria and parasites, including the ones that can cause diseases in dogs such as Lyme disease, Rocky Mountain Spotted Fever and Bartonellosis. Flea bites can cause miserable itching and skin infections. Fleas can also carry and transmit tapeworms and bacteria to your dog, potentially resulting in diseases like Bartonellosis. Protect your dog with essential oils, an immune-boosting diet and ultrasonic tick repellants. Use herbs and post-bite homeopaths as needed.