List of pathogens by size
# List of pathogens by size

This is a list of pathogens (human or otherwise) in order of size.

| Classification | Binomial name | Common name | Dimension | Size | Reference |
| - | - | - | - | - | - |
| Flatworm animal | Eucestoda | Tapeworm | length (maximum) | 25 m | Eucestoda |
| Nematode animal | Loa loa | Loa loa | length (female) | 20-70 mm | Loa loa |
| Arthropod animal | Cymothoa exigua | Tongue-eating louse | length (female) | 8-29 mm | Cymothoa exigua |
| Nematode animal | Enterobius | Pinworm | length (female) | 8-13 mm | Pinworm (parasite) |
| Arthropod animal | Pediculus humanus capitis | Head louse | length | 2.5-3 mm | Head louse |
| Flatworm animal | Eucestoda | Tapeworm | length (minimum) | 1 mm | Eucestoda |
| Arthropod animal | Sarcoptes scabiei | Scabies | length (female) | 0.3–0.45 mm | Sarcoptes scabiei |
| Metamonad | Giardia lamblia | Giardia | length | 10-20 μm | Giardia lamblia |
| Fungus | Candida albicans | Yeast infection | diameter | 10-12 μm | Candida albicans |
| Bacterium | Borrelia burgdorferi | Lyme disease | length | 10 μm | Borrelia burgdorferi |
| Alveolate protist | Plasmodium | Malaria | diameter (sexual form) | 7-14 μm | |
| Fungus | [many] | [many] | width of hyphae | 2-10 μm | Fungus |
| Bacterium | Yersinia pestis | Plague | length | a few μm | Yersinia |
| Bacterium | Mycobacterium tuberculosis | Tuberculosis | length | 2-4 μm | |
| Alveolate protist | Plasmodium | Malaria | diameter (asexual form) | 1-2 μm | |
| Bacterium | Mycoplasma genitalium | (one cause of urethritis) | length | 600 nm | Mycoplasma |
| Virus | HIV | HIV | diameter | 120 nm | HIV |
| Virus | Orthomyxoviridae | Influenza | diameter | 50-120 nm | Orthomyxoviridae |
| Virus | Rhinovirus | Common cold | diameter | 30 nm | Rhinovirus |
| Virus | Porcine circovirus | Porcine circovirus | diameter | 17 nm | Porcine circovirus |
