question: A vector is an organism that carries what disease-causing microorganisms from one person or animal to another?
distractor3: genome
distractor1: microbe
distractor2: microbe
correct_answer: pathogen
support: Still other pathogens are spread by vectors . A vector is an organism that carries pathogens from one person or animal to another. Most vectors are insects, such as ticks and mosquitoes. These insects tend to transfer protozoan or viral parasites. When an insect bites an infected person or animal, it picks up the pathogen. Then the pathogen travels to the next person or animal it bites. Ticks carry the bacteria that cause Lyme disease. Mosquitoes ( Figure below ) carry West Nile virus. Both pathogens cause fever, headache, and tiredness. If the diseases are not treated, more serious symptoms may develop. Other diseases spread by mosquitoes include Dengue Fever and Yellow Fever.