Date of Award

January 2015

Document Type


Degree Name

Master of Science (MS)



First Advisor

Jefferson A. Vaughan


Mosquitoes transmit arboviruses, haemosporidian protozoa (e.g., malaria), and filarioid nematodes. Many of these mosquito-borne pathogens occur together and transmission cycles are occurring concurrently. Despite this, mosquito pathogen transmission cycles are largely studied independently of one another. Considering the large temporal and spatial overlap among these various transmission cycles, the question becomes, what kinds of interactions are occurring between parasite transmission cycles and arboviral transmission cycles? Also, some species of mosquito are incapable of transmitting some species of arbovirus. Therefore, there must be natural barriers to prevent arbovirus infection and transmission. These barriers include the midgut barrier and the salivary gland barrier. Parasites that develop within mosquitoes have the potential to disrupt (overcome, etc.) these barriers. To further understand these interactions, I surveyed the song birds in northwest MN and screened them for haemoparasites and West Nile virus seropositivity. I focused on the behavioral aspects of microfilariae (MF) because they are known to disrupt the midgut barrier of their arthropod hosts. I found high prevalence and polyparasitism of haemoparasites infecting song birds in northwest MN. It was determined that MF of the American robin, Culex pipiens mosquitoes and West Nile virus was not an important system for enhanced viral transmission. Melatonin may play a role in the regulation of nocturnal periodicity behavior of MF, but other factors most likely contribute as well.