Related Clues:
- Cause of head-scratching, perhaps
- Some tiny rods and spheres
- Single-cell organism
- Fumigation targets, sometimes
- Students may be searched for them in grade school
- Neosporin target
- Antibiotic targets
- Grade-schooler's woe
- Head parasites
- Some ectoparasites
- Germs
- Cause of some head scratching?
- Microscopic organisms
- Care a bit about sources of diseases
- Single cell micro-organisms