1. Pathogen Life Cycles Pathogens/Parasites Alternate Between Animal Hosts Schistosomiasis: Macroparasite Zoonotic Disease: Human Infection, “Accident” Lyme DiseaseWest Nile Fever

2. Lyme Disease Most Common Vector-Borne Infection in Northern Hemisphere Northeast: 4+ Species: Enzootic Cycle Borrelia (pathogen) Black-legged Tick (vector) Small, Large Mammal Hosts

3. Ixodid Tick Year 1 Egg Larva Blood Meal White-footed Mouse, Other Small Mammal Infection? Molt/Quiescent Year 2 Nymph Blood Meal Small Mammal Zoonotic Infection Adult Blood Meal (♀), Deer Reproduce

4. Enzootic Cycle, Lyme (Penn State Univ.)

5. Ixodid Ticks (CDC)

6. NYS: Lyme Disease; Glavanakov et al 2001

7. Lyme Disease: NYS, Cases & Rates

8. Schistosomiasis  200 x 10 6 Infections Worldwide  Tropical, Freshwater Snails  5 Macroparasites  Complex Lifecycle: 2 Hosts, 2 Reproductive Modes

9. Schistosomiasis  (Originally) Disease of Herbivores  Infects Cattle, Jumped to Humans?  Human Parasitic Disease: Chronic Infection/Cognition Impact Second to Malaria/Economic

10. Schistosome Life Cycle

11. Snail: Mother Sporocyst, Asexual Reproduction, Daughter Sporocysts, Daily Release of Cercariae Human: Schistosomules Mature as Male or Female, Sexual Reproduction

12. West Nile Virus WNV: Arbovirus, Arboviral Encephalitis N America: First Noted 1999 Across Continent, Central America Reservoir: Birds Vectors: Mosquito Spp. Secondary Infection – Mammals Humans: Zoonosis

13. WNV: Geographic Distribution (CDC)

14. WNV Birds - 2009 (USGS)

15. WNV : Human cases, 2012

16. WNV Life Cycle (Stanford)

17. WNV Life Cycle RNA Virus: High Mutation Rate Mosquito: Innate Immunity Viral Master Sequence Mutant Cloud: Quasispecies, High Diversity Bird: Vertebrate Immunity Master Sequence, Low Diversity

18. WNV Life Cycle Viral R 0 : Must Reproduce Sequentially in Two Different Environments Trade-offs?

19. WNV Vectors Mosquito Spp and Zoonosis Risk Enzoootic Cycle: Culex pipiens Ornithophilic; Fewer Mammal Meals “Bridge Vectors” Prefer Mammals; Risk to Humans? Aedes Spp.

20. WNV Vectors 1.Abundance 2.Fraction Blood Meals from Mammals 3.WNV Prevalence Pr[Fed Infected Bird & Acquired WNV] Fraction of Mosquito Sp. Carrying WNV 4.Vector Competence Given Infection, Pr Will Transmit to New Host

21. WNV Vectors (Kilpatrick et al. 2005) Bridge (Aedes)Ornithophilic Abundance 21%37% Mammal Meals 86%19% WNV Prevalence 5%95% Competence 17%38% Risk 4.5%80.2%

22. WNV Vectors/Zoonosis Risk Control Ornithophilic Spp. Small Set of Breeding Sites Tires, Gutters, Open Pools Around Human Habitations Wetland Intervention Unnecessary