Epidemiology

Question 1

Epidemiology

Answer 1

Science that evaluates occurrence, determinants, distribution, and control of health and disease in a human population. John Snow was the first epidemiologist.

Question 2

CDC

Answer 2

Develops and applies disease prevention and controls. Also focuses on environmental health and health education. WHO is world counterpart.

Question 3

Goals of Epidemiology

Answer 3

Determine: causative agent, reservoir of disease agent, mechanism of transmission, host/environmental factors that facilitate disease development, and the best control measures.

Question 4

Sporadic Disease

Answer 4

Occurs occasionally and at sporadic intervals.

Question 5

Endemic Disease

Answer 5

Steady low-level frequency at regular interval.

Question 6

Hyperendemic

Answer 6

Gradually increases frequency above endemic level.

Question 7

Outbreak

Answer 7

Sudden, unexpected occurrence of disease, usually in a limited segment of population.

Question 8

Epidemic

Answer 8

Sudden increase in frequency of disease above expected level. Index case = first case.

Question 9

Pandemic

Answer 9

Increase in disease occurrence within a large population, over wide region (worldwide).

Question 10

Epidemiological Methods

Answer 10

Public health surveillance: protect population, improve public health, apply methodological approach to identify potential problems (review death certificates, field investigation, actual investigation).

Question 11

Morbidity Rate

Answer 11

Incidence rate; # of new cases in given time / # individuals in population

Question 12

Prevalence Rate

Answer 12

Total number of individuals infected at a given time.

Question 13

Mortality Rate

Answer 13

deaths due to given disease / # individuals with disease

Question 14

Types of Epidemics

Answer 14

Common Source: single, common, contaminated source (food)

Propagated: one individual with infection spreads it to a susceptible group

Question 15

Herd Immunity

Answer 15

If greater than 70% of a population is immune to a specific disease, the susceptible individuals will be well protected against it.

Question 16

Emerging Infections in US

Answer 16

Emerging disease mortality in US has increased since 1982. Due to population growth, increased travel, habitat disruption, microbial evolution and resistance development, inadequate public infrastructure, climate change, social unrest, food processing, technology, immunosuppression.

Question 17

Nonsocomial Infections

Answer 17

Hospital-acquired; affect 10% of all hospital patients; commonly caused by normal microbiota; UTI, pneumonia, surgical site infection, blood infections.

Question 18

Epidemic Control Measures

Answer 18

Reduce or eliminate reservoir of infection; break connection between reservoir and host; reduce number of susceptible hosts (vaccinate)

Question 19

Vaccines

Answer 19

May consist of killed, living, attenuated, or inactivated bacterial toxins, cell material, recombinant vectors, or DNA. Induce antibodies and activated T cells to protect against future infection.

Question 20

Whole Cell Vacines

Answer 20

Usually either killed or attenuated; may not work on occasion and attenuated versions may affect immunosuppressed individuals

Question 21

Acellular Vaccines

Answer 21

Use of subunits of microbes to vaccinate. i.e. capsular polysaccharides, recombinant surface antigens, and inactivated exotoxins.