Diseases Caused by Fleas: Excessive scratching may be the first sign that your pet has an annoying flea problem. But it may also indicate a larger health issue. Fleas can cause a wide range of diseases that deprive your pet of energy, cause sores and affect overall health, such as:

• Flea Allergy Dermititis
• Anemia                       
• Tapeworm
• Bartonella (Cat scratch disease)
• and many others

Diseases Caused By Ticks: Ticks can transmit diseases that actually threaten your pet's life. Frontline is an important defense against ticks. Lyme disease, if caught early, can be treated well with antibiotics.  Other tick related diseases are more dangerous. Contact our office if you notice any of these symptoms:

• Lameness
• Fever
• Loss of Appetite
• Fatigue
• Enlarged Lymph Nodes

(Source: http://frontline.us.merial.com/index.asp)