Class 1 Flashcards
What percent of zoonoses caused IED?
75%
Most common non-human animal sources of EID?
insects, domesticated animals, swine, bats, rodent
Stages of transmission
Stage 1: agent in animals only
Stage 2: primary infection
Stage 3:
Stage 4:
Stage 5:
What causes decreases in ID 20th century?
housing, nutrition, antibiotics, hygiene, immuniations, safter food/water
Factors influence in emergence of diseases
changes in demographics, environmental changes, international commerce, microbial adaptation, changes in tech
Determinants of ID Emergence and Spread
Tech
Breakdown PH measures
Factors that increase ID
rising world pop: Developing countries huge rise, Industrial countries- near zero
What is Immune senescence
The aging of the immune system
factors in emerging ID
Greater Host susceptibility: malnutrition, Immunosuppressive therapy, HIV, malignancy, transplantation
Factors in EID
Social and behavioral factors: culture, family work dynamics, travel, antimicrobial use, sexual contact…
IED factors
Day care centers: increase Dual incomes, soread
factors IED
Smokinf, IDU (increase HIV, HepB,C, Adventurous activities, spelunking etc.
Factors increasing EID
Administered in ways that increase resistance
result = increase resistance and outbreaks
Factors increasing EID
Farm to table: many different points food can become contaminated
Factors affecting EID
Climate variability: southern oscillation index: el nino/la nina. End result: winter with el nino- dry/warm, wet/warm: great potential affect vector born disease.
Factors affecting EID
Global temp changes
MDR pathogen
Multi-drug resistant
Influenza has three main types A, B, C
A/B causes yearly epidemics in the winter:
C cause little if any harm to humans
A causes pandemics, most dangerous to humans, wide range of hosts, rapid mutation, capacity to cause really serious disease
Influenza subtypes
A subtypes: HA and NA surface antigens
18 HA subtypes known pair with 1 of NA subtypes
Preference of the avian bird flu depends on what?
The orientation of the linkage and binding to polymers
Antigenic drift
gradual accumulation of mutations in HA and NA over time- lack of proofreading enzymes, many replication errors
New strain- same subtype as older strains
humans have partial immunity to new strain
disease generally not terribly severe
Requirements for pandemic
new virus emerges and pop has little/no immunity
able to replicate
transmitted to humans
Anitgenic shift
sudden change from one subtype to another. Major reassortment in HA or NA genes
What is One Health Approach commonalities
collaborative,
