bios242 unit 4 epidemiology (4/4)

Practice questions and answers covering the fundamental concepts of epidemiology, including epidemic patterns, measurements, and public health institutions based on the lecture transcript.

What is the definition of epidemiology?

The field that studies diseases in populations.

Who are epidemiologists?

Scientists who study epidemiology and its impacts on public health.

What are three examples of recent global pandemic scares mentioned in the text?

COVID-19, H1N1, and avian flu.

What is an index case?

The first person with the disease in an epidemic.

How do epidemiologists determine the severity of an outbreak?

They review how many people have the disease within a given area.

When do researchers classify an outbreak as an epidemic?

When the number of cases is greater than expected for that area.

Why is the annual flu generally not considered an epidemic?

Because thousands of people get it each year and it is not a significant change in numbers unless it exceeds expectations.

What name is given to the number of deaths epidemiologists expect for a certain time?

The seasonal baseline.

On an epidemiological chart, how is the seasonal baseline visually represented?

By a thin black line.

How is the actual percentage of deaths due to pneumonia and influenza represented on a chart?

By a red line.

When does an epidemic occur according to mortality chart lines?

When the red line (actual percentage) is greater than the thin black line (seasonal baseline percentage).

By what two factors can classified epidemics be further categorized?

The source of infection and the geographic location of the infection.

What is a point-source epidemic?

An epidemic that arises when the infectious agent is from one source and all infected individuals are exposed at the same time.

Provide an example of a point-source epidemic.

Diarrhea caused by contaminated food at a restaurant.

What is a common-source epidemic?

An outbreak that begins from a single source where exposure lasts for a longer period, such as days or weeks.

In what year and location did patients develop Legionnaires’ disease from a single source?

Flint, Michigan during the summer of $2014$.

Which bacterium causes Legionnaires’ disease?

Legionella pneumophila.

What is a propagated epidemic?

An epidemic where the first patient spreads the disease to others, who then spread the infection to more people.

What is a pandemic?

An epidemic that spreads across more than one continent.

Besides COVID-19, what two other infectious diseases are listed as pandemics?

HIV and influenza.

What is the term for a disease that occurs frequently in a particular region over a long period of time?

Endemic.

Where is Lyme disease considered an endemic disease?

The northeastern United States.

What is a sporadic disease?

A disease that appears occasionally at random times and outside its normal range.

In which state is the appearance of Lyme disease considered sporadic?

Utah.

What is the full name of the CDC?

Centers for Disease Control and Prevention.

What is the goal of CDC scientists in public health?

To find the sources of diseases, establish mechanisms of transmission, and develop methods for preventing diseases.

What are three strategies used by the CDC to prevent disease?

Setting standards for cleanliness, creating immunization plans, and educating the public.

How are reportable diseases defined?

Diseases that are highly dangerous, contagious, or unusual and must be tracked by authorities.

List three examples of reportable diseases.

Coronavirus, Dengue fever, and measles.

Are reportable diseases always required by law to be reported?

No, some are required by law while others are reported on a voluntary basis.

What is the full name of the WHO?

World Health Organization.

What is incidence?

A measure of the number of new cases in a population during a specific time.

What is prevalence?

The total number of existing cases in a population.

Why is it unlikely that all infectious diseases will be eliminated?

Because infectious diseases can both emerge and reemerge.

What is a reemerging disease?

A disease that was previously controlled but is appearing again.

What is an example of a reemerging disease mentioned in the text?

Measles.

Why do sporadic outbreaks of measles occur in the United States?

Many individuals choose not to get the effective vaccine.

What is an emerging infectious disease?

A disease caused by newly identified microbes.

What is provided as an example of an emerging infectious disease?

COVID-19.

What identifies an epidemic if only a few hundred people are affected?

If the disease is rarely seen in that region (the number is greater than expected).

Which institution quantifies the incidence and prevalence of infectious diseases in the United States?

The Centers for Disease Control and Prevention.

How long does exposure typically last in a common-source epidemic?

Days or weeks.

In what way are the CDC and WHO related in their work?

They work together to measure the incidence and prevalence of infectious diseases globally.

What does prevalence measure in a population?

The total number of existing cases.

If an epidemic is present on multiple continents, what is it called?

A pandemic.

When is the seasonal baseline used?

It is used as a reference to determine if actual deaths from diseases like influenza have reached epidemic levels.

What term describes the first case that alerts epidemiologists to an outbreak?

The index case.

Which bacterium was associated with the Flint, Michigan hospital in $2014$?

Legionella pneumophila.

What term describes the frequent occurrence of a disease in a specific area over a long time?

Endemic.

What measure tracks the number of new cases specifically?

Incidence.