Ch. 9 Flashcards
epidemic
widespread disease outbreak within a particular region at a particular time
emerging pathogen
newly identified agents or pathogens that previously cause only sporadic cases and are now causing emerging diseases
koch’s postulates limitations
don’t apply to NONINFECTIOUS diseases, some infectious diseases r hard 2 grow and isolate bc can’t recreate exact setting in labs and also ethical issues and also maybe microbes can become attenuated
reemerging pathogens
infectious agent that was under control but is now resurfacing
biological vector
pathogen has part of its life cycle in an insect. pathogen is relying on the insect to live. Ex: mosquito bite = malaria
mechanical vector
pathogen “hitches a ride” but doesn’t have part of its life cycle in the vector. Ex: fly lands on dog poop and then on your lunch
exogenous source
external to the host.
environmental: contaminated food, water, medical equipment
animals: transmit zoonotic diseases to people
humans: transmit communicable infections from one person to another
endogenous source
came from the host’s own body.
misplaced normal microbiota: bacteria living harmlessly on skin can enter surgical incisions to cause postoperative infections
disrupted microbiota and opportunistic pathogens: yeast in the vagina may proliferate and cause infection after antibiotics kill off bacterial neighbors
herd immunity
occurs when a high percentage (~85%) of the population is immune.
- prevents a pathogen from finding enough susceptible people in the community to persist
- allows a small # of individuals to remain unvaccinated
- only protection for those unable to receive immunizations due to medical reasons
morbidity
existence of disease in a population
subclinical case
also called asymptomatic cases. infections that fail to generate symptoms
opportunistic pathogens
infect weakened/immunocompromised hosts
true pathogens
infect host no matter what
descriptive epidemiology
describe the occurrence and distribution of disease. who’s infected, where cases r occurring, when cases r occurring.does NOT reveal cause of disease *often use these first bc less $ and time consuming than analytical studies *correlation studies, case reports, cross sectional studies
analytical epidemiology
what, why, how *what caused disease, y r peeps gettin it, how it can b prevented or treated *more challenging and time consuming and $ *observational and experimental studies
bacteria that are most common causes of HAIs
Staphylococcus aureus, Escherichia coli, Clostridium difficile, and Pseudomonas aeruginosa
what can help limit the spread of HAIs?
hand hygiene, sanitizing equipment, sterilizing instruments, limit patient transport, follow proper aseptic techniques, gloves DO NOT replace hand hygiene, using PPE, single patient equipment use
prevalence
morbidity in a given pop during a SPECIFIED TIME *we need 2 know prevalence 2 know how the disease is affecting the pop
incidence rate
of NEW CASES in a pop at a particular time *if we put preventative measures in place and wanna know if they’re working, should c incidence rate decrease if preventative measures r working
what does correlation not imply?
causation. correlation looks at associations that can uncover disease risk factors
after a reportable disease is diagnosed by a healthcare provider, who do they have to report it to?
state or local health authorities
