Related Clues:

• Cause of some head scratching
• Wingless blood-suckers
• Canine pests
• Parasitic pests
• Mouthwash target
• Disinfectant's target
• Itch producers
• Lysol targets
• Disgusting insects
• Dog bane
• Cold carriers?
• Pathogens
• Grownup nits
• Microbes
• Grown-up nits