Factors influencing interactions between ticks and wild birds Amy A. Diaz Faculty Sponsor: Dr. Howard Ginsberg

Objective Investigate the factors influencing the associations between ticks and wild birds Increase awareness of those most at risk for Lyme disease infection Decrease the number of human infections Especially in the young and elderly

Research Analyze bird characteristics and possible effects on tick recruitment, attachment, and drop-off time. Infection status Body weight Body temperature Foraging habits

Reported cases of Lyme disease by year United States,

Lyme disease Causative agent Spirochete bacteria: Borrelia burgdorferi (USA) Vector Ixodes scapularis tick (Eastern United States) Reservoirs Rodents Birds NOT Deer

Symptoms Often asymptomatic Summer-time “flu-like” symptoms Fever, fatigue, joint and muscle pain Erythema migrans (EM) rash If left untreated Neurologic, cardiac, rheumatoid complications

Transmission Tick acquires infection from infected and infective reservoir, while taking a blood meal. During subsequent feedings, susceptible hosts may be infected if tick is attached for greater than 24 hours.

Reservoirs Competent reservoirs White-footed mice Deer mice Backyard bird species American Robin Song Sparrow

Analysis Bird banding data available from Fire Island, New York and literature Statistical analyses Chi 2 Test Fisher’s Exact test Regression Analysis

Tick Recruitment No correlation between larval recruitment and the following: Nymphal recruitment Bird weight Body temperature Foraging habits Migration versus local habitats

Attachment & Feeding No correlation between tick attachment and successful feeding and the following: Bird weight Body temperature

Attachment No variation between species Except for Northern Cardinal

Tick Drop-off Time No effect of body weight and temperature on drop-off time

Drop-off Ticks remained attached longer to and dropped off later from birds infected with B. burgdorferi 1997 & 1998 Ixodes scapularis & Amblyoma ticks Gray Catbirds & Song Sparrows

Drop-off Additionally, the greatest change in drop-off time between infected and uninfected birds tended to be seen in birds with significant weight loss. Indicator of stress Species susceptibility to stress Further study warranted

Bird Species Ratio t + /t - Mean t - (hr) Weight (g)% Weight Change Gray Catbird Song Sparrow American Robin Northern Cardinal Eastern Towhee

Conclusions No correlations between the following: Larval Recruitment Nymphal Recruitment Bird Weight Body Temperature Foraging Habits Attachment & Successful Feeding Bird Species Bird Weight Body Temperature

Conclusions No correlations between the following: Drop-off Time Bird Weight Body Temperature Evidence for relationship between infection status and tick drop-off time However, no implications for Lyme disease transmission

Implications Birds are significant players in the transmission cycle of Lyme disease. Factors affecting the attraction of ticks to birds, as well as successful feeding and length of time attached, are key to understanding the importance of wild birds as reservoirs of disease. Infection status Stress

Implications Lyme disease is preventable Realize importance of common wild birds as reservoirs for disease Hosts to infected vectors Competence to infect feeding vectors Disease amplification Precautions to protect family

Acknowledgments Maxon G. Balmforth Shaibal Mitra P.A. Buckley Howard S. Ginsberg

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