1. evolutionary medicine diseases tracking hosts, and jumping to new hosts virulence evolves resistance evolves antibiotics and evolutionary responses openclipart.org

2. chapter 18.1-18.4 Virulence Flu example! Antibiotic resistance: our bee model

3. Cytomegalovirus

4. pathogens tend to track hosts Hosts are ENVIRONMENTS immune response, nutrients, habitat density, physiological limits Some pathogens are specialists on narrow range of hosts, others are generalist, broader niche

5. Habitat shift is Often to a similar Environment (Related species)

6. But not always similar! SARS virus apparently Jumped from bats To civets To humans

7. First section Pathogens track their habitat. Cospeciation, biogeography. But sometimes migrate. Tends to need contact and/or evolutionary similarity. Do poorly at first then adapt. This tells us about pathogen ecology AND how we make vaccine. It is basically Darwin's postulates involved with biogeography and introduction.

8. Coinfection Hemagglutinin evolution in flu virus can evolve through mutation as well as horizontal gene transfer from other virus when in same host Required new vaccine to be developed 2002-03 2003-04

9. Avian strain evolved Virulence In dense aggregations Human strain evolved With human Environmental background

10. Bats also A common Source Human strain evolved With human Environmental background

11. 2013: new outbreak of SARS - like virus In Middle East, appears again to originate in bats Again, we figure this out using PHYLOGENETICS

12. Virus artificial selection = vaccine Variation (high mutation rate, large population size) May be heritable Differential survival Ones that survive carry genes that increased fitness How vaccine is developed using adaptation as a tool

14. Awful Orange Give one to UP TO 2 People YOU CAN REACH without standing Green Goo Give one to Next nearest person (However far)

15. Discuss what element of pathogen biology did we simulate? what happened to each pathogen? what were the parameters in our model? what would you change?

17. What happens when a dense population with different demographics and migration patterns... Meets a sparse population that is naïve to the pathogen?

18. Larger number people one interacts with Virulence Virulence associated w growth rate: uses host resource, by-product is disease

19. Larger number people one interacts with Virulence

20. Why selection affects virulence? 1.Population dies out if uses up resources before it finds more (general, selection is at level of host population) 2.Less quick-growing strain loses reproductive advantage to faster (more virulent) strain, selection is within host 3.Note selection (evolution) and competition (ecology) are analogous ways to discuss differential performance of diversity

21. Lateral gene transfer Diversity effect of sexual recombination, across diverse microbial taxa SUPERBUGS

23. Strategy to cycle different antimicrobials in facility - helps population resistant to one antibiotic now be exposed to a second (can evolve) Instead different treatment for each patient appears to have theoretical/model advantage

24. Bergstrom's work suggests using multiple drugs in random design is probably best for limiting bacterial evolution

25. Not just in humans, HUGE usage in animals leads to resistant strains in livestock AND US

26. no class thursday Away at funeral We will finish chapter 18 (aging and cancer among the topics) next Tuesday, stop there Exam next Thursday 11/21