“Scratching” the Surface: Ticks and Sarcoptic Mange (Sarcoptes scabiei) in American Black Bears
Restricted (Penn State Only)
- Author:
- Tiffin, Hannah
- Graduate Program:
- Entomology
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- June 01, 2022
- Committee Members:
- Gary Felton, Program Head/Chair
Edwin Rajotte, Major Field Member
Erika Machtinger, Chair & Dissertation Advisor
Justin Brown, Outside Unit & Field Member
Jennifer Mullinax, Special Member
Mark Ternent, Special Member
Joyce Sakamoto, Major Field Member - Keywords:
- black bear
ursus americanus
mange
sarcoptic mange
parasite
host-parasite interactions
carnivores
red fox
grey fox
coyote
ticks
Ixodes scapularis
backlegged tick
Sarcoptes scabiei
scabies
neglected diseases
zoonotic disease
zoonoses
One Health
Pennsylvania
wildlife
disease spillover
disease ecology
emerging disease - Abstract:
- A fundamental challenge of disease ecology is to untangle cause from effect. This is particularly difficult in wildlife systems as individuals are not continually observed, often observed over short time-periods, and typically have numerous infestations and/or infections at any given time. The effects of sarcoptic mange in wildlife systems have been difficult to untangle for these and numerous other reasons, particularly related to the small size of the parasitic mite that causes mange in animals and scabies in humans. Though Sarcoptes scabiei has been known to cause disease in mammals for thousands of years, it is still considered a neglected disease of humans and a pan-emerging disease in animals, due to historically limited research and currently expanding host range. Black bears (Ursus americanus) are one of these newly affected hosts, with Pennsylvania as the epicenter of increasing numbers and expanding geographic range of sarcoptic mange in black bears. As a new disease affecting black bears, there are still many unknown variables and outcomes associated with this disease, including the individual- and population-level health effects of mange, the ability of black bears to recover, and the overall management implications and mitigation options for this disease. This research sought to address several critical gaps by evaluating the manifestation of disease in black bears and historically affected sympatric carnivores, the ability of black bears to recover from mange, and co-infestation with other common ectoparasites in the Northeast, namely ticks. Ticks and the pathogens they transmit are another emerging threat to wildlife and human health and are a prime example of the importance of a One Health framework to consider the spheres of environment, human, and animal health in disease surveillance, control, and management decisions. The overall goal of this research was to characterize disease spillover and management in newly affected species and geographic ranges.