Host-feeding patterns of suspected West Nile virus mosquito vectors in Delaware, 2001-2002.

This research investigated the feeding patterns of mosquito species suspected of transmitting the West Nile virus in Delaware, USA. The study was conducted over two years and employed various collection methods to gather mosquitoes from diverse habitats. The feeding habits of these species were analyzed, determining their preference towards specific host species and their potential roles as pathogen vectors.

Methodology

• The researchers used four different methods to collect mosquitoes, namely, omnidirectional Fay-Prince traps, Centers for Disease Control-type light traps, gravid traps, and human-landing collections.
• The study was carried out over two transmission seasons of the West Nile virus in 2001 and 2002.
• Mosquitoes were collected from nine different sites throughout Delaware, from varied habitats such as salt marshes, brackish water regions, woodlands, a tire dump, a racetrack, and a mushroom farm.
• The blood-meals of the mosquitoes were analyzed using a sandwich-type enzyme-linked immunosorbent assay, primarily for five common host species: rabbits, dogs, deer, horses, and chickens.

Findings

• Significant host-feeding data were gathered from eight mosquito species.
• Anopheles quadrimaculatus, Coquillettidia perturbans, and Aedes albopictus were the species that showed a strong preference for mammalian hosts (mammalophilic).
• Culex pipiens was identified as the most bird-preferred (ornithophilic) species.
• Aedes albopictus was the most attracted to humans (anthropophilic), while Ae. vexans and Cq. perturbans showed relatively low attraction to humans.
• Culex salinarius displayed the most diverse host-feeding activity among the studied species.

Implications

• Based on feeding behavior, the researchers identified Culex pipiens and Culex salinarius as the most likely bridge vectors for West Nile virus, suggesting their role in disease transmission between different species.
• The paper also discusses potential circumstances under which other species may serve as bridge vectors.
• The findings help deepen our understanding of mosquito feeding habits, potentially aiding in predicting and disrupting disease transmission cycles.