| Bakterien | Viren | Pilze | Parasiten |
| F | |||
| Flavimonas oryzihabitans (-) | Filoviren | Fonsecaea Spp. | Fadenwürmer (Nematoda) |
| Flavobacterium Spp. (-) | Flaviviren | Fusarium Spp. | Fasciola Spp. |
| Francisella tularensis (-) | FSME-Virus | Fasciolopsis buski | |
| Fusobacterium Spp. (-) | Filarien | ||
| Filzlaus | |||
| Fliegen | |||
| Flöhe (Siphonapterida) | |||