Answer:
Some virus or bacteria that is transmited without a carriage, as a sexual transmited disease
Explanation:
Usually vectors are animals, and mainly arthropods (mosquitoes, ticks, beetles, fleas, etc).
There are 5 ways to transmit a disease
Oral: by eating it, vector: some arthropods carry the disease and passed it out, fomites: something like a knife has a pathogen and when you cut yourself you get infected, aerosol: is in the air, zoonotic: as an example if a rat bites you and you get infected with rabia, direct contact: as an example when someone pass HIV to other person through sexual contact
