Agents like mosquitoes and rat fleas that carry disease-causing organisms are called _________.
vectors
Organisms like mosquitoes and rat fleas that carry pathogens or disease causing organisms are called vectors. Vectors carry diseases from one infected person to a healthy person.
For example, female Anopheles mosquitoes carry a protozoan Plasmodium which causes malaria and rat fleas carry a bacterium Yersinia pestis which causes bubonic plague.