1
What exactly
is a pandemic?
CDC NERD Academy
Grade level
Suggested time
6–12 75 minut
es
Overview
In this module, students are
introduced to public health
and how public health
workers protect and
improve the health of
communities. They analyze
characteristics of specific
disease events to determine
the level of disease
occurrence (e.g., endemic,
outbreak, epidemic, or
pandemic). Using
information on a fictional,
novel emerging respiratory
disease (NERD), students
will track disease
progression over time.
Learning objectives
1
After
this module, students should be able to
Describe the purpose of public health and provide
examples of public health actions
Compare and contr
ast the roles of a healthcare provider
and epidemiologist in improving health
Evaluate patterns of disease occurrence to differentiate
among ende
mic, outbreak, epidemic, and pandemic levels
of disease occurrence
Describe the circumstances when a virus would be
consi
dered a novel virus and describe its role in emerging
pandemics
Track events over time and location to determine when
NER
D becomes a pandemic
STEM connections & standards
STEM connections: Science: classification; Social studies:
timeline, mapping
Problem-based skills: Identifying trends, decision making,
collaborative performance
Epidemiology and Public Health Science Core Competencies: HS-EPHS1: Epidemiologic
Thinking and a Public Health Approach; HS-EPHS2: Public Health Surveillance
https://www.cdc.gov/careerpaths/k12teacherroadmap/pdfs/ephs-competencies.pdf
National Health Education Standards: Standard 1: Students will comprehend concepts related to
health promotion and disease prevention to enhance health. Standard 5: Students will demonstrate
the ability to use decision-making skills to enhance health.
https://www.cdc.gov/healthyschools/sher/standards/index.htm
Next Generation Science Standards: Science & Engineering Practice(s): Asking Questions and
Defining Problems; Analyzing and Interpreting Data; Engaging in Argument from Evidence;
Crosscutting Concept(s): Patterns http://www.nextgenscience.org/get-to-know
Module 1 Defining a pandemic
Timeline
1
Introducing the content (30 minutes)
Students watch the “What exactly is a pandemic?” video (12:39 minutes) to learn about
public health, pandemics, and other levels of disease occurrence. Teachers can assess
student knowledge of the video content using the Knowledge Check. The class can
further discuss the role of an epidemiologist using the Career Spotlight.
2
Activity (35 minutes)
In groups, students analyze data from health-related events to determine levels of
disease occurrence. Then, they track NERD cases to justify when to declare a pandemic.
Teachers can watch an activity demonstration video (2:48 minutes) that illustrates how to
teach this activity in the classroom.
3
Class discussion (10 minutes)
As a class, students apply their knowledge to answer questions about pandemics.
Vocabulary
Case, c
luster, endemic, epidemic,
epidemiology, expected level, novel virus,
outbreak, pandemic, public health.
See Definitions.
Materials
Handouts, scissors, and tape.
Meet Ezra,
an epidemiologist
Learn more about an epidemiologist’s role in the Career
Spotlight and the “What exactly is a pandemic?” video.
Module 1 Defining a pandemic CDC NERD Academy Page | 2
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Teacher preparation
Preview videos.
Make copies of handouts.
Cut out Level of Disease E
vent Cards,
NERD Newsfeed Posts, and NERD
Pandemic Label Cards.
Make copies of the NERD Factsheet (
one
per group) or an enlarged classroom
version.
The NERD Factsheet is not required for
this lesson but may be useful as a
reference.
The NERD Factsheet may be re-used
across modules if previously distributed
to students.
Create a classroom version of the Level
of Disease Classification and the NERD
Timeline (e.g., re-create on whiteboard or
large poster or prepare to project the
image).
Videos
“What exactly is a pandemic?” video
(12:39 minutes) for students
Activity demonstration video (2:48
minutes) for teachers
www.cdc.gov/scienceambassador/
nerdacademy/defining-the-pandemic.html
Handouts
Knowledge Check: Level of Disease
(one per student)
Career Spotlight: Epidemiologist (one
per student or
classroom copy)
Level of Disease Event Cards (one set
per gr
oup)
Level of Disease Classification (one per
s
tudent)
NERD Newsfeed Posts (one per group)
NE
RD Timeline (one per student
)
NERD Pandemic Label Cards (one for
each group)
Introducing the content (30 minutes)
Say aloud
You are likely quite familiar with the word ‘pandemic,’ but do we know exactly what
that means? During this video, you will learn how epidemiologists, also known as
disease detectives, classify levels of disease occurrence as endemic, or as a cluster,
outbreak, epidemic, or pandemic by using number of cases, location, and time. You
will also learn how health is defined and about the people involved in keeping us
healthy as individuals and as whole communities.
2 Hand out the Knowledge Check: Level of Disease. Allow students 3–5 minutes to answer the
q
uestions on their own. Then, review as a class using the Knowledge Check: Answer Key
provided.
3 Hand out or display the Career Spotlight. Discuss the role of an epidemiologist.
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Activity: Part 1 (15 minutes)
Say aloud
Now that you have seen how an epidemiologist uses data to classify levels of disease
occurrence, your team will examine eight different disease events. You will compare
patterns in the number of cases, location, and time and categorize them into one of
four levels of disease: endemic, outbreak, epidemic, and pandemic. You will use
evidence from the event cards to justify your choices.
Each card reflects actual data from a historic disease event. With any time remaining
after you categorize the events, your team can propose a disease which could be
responsible each event.
1 Divide students into groups of 3–5. Hand out one set of Level of Disease Event Cards per
g
roup and one Level of Disease Classification handout per student.
2 Ask groups to categorize event cards into levels of disease occurrence (endemic, outbreak,
epidemic, pandemic) and record their categorization choices on their Level of Disease
Classification handout.
If time permits, groups could propose a disease which might be responsible for each event.
3 Ask for volunteers to share event card categorization and possible diseases while completing
the classroom version of Level of Disease Classification. Discuss criteria used for
categorizing events into each level of disease occurrence and allow students to recategorize on
their info sheet as necessary.
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Activity: Part 2 (20 minutes)
Say aloud
Now that you know more about how public health experts use levels to describe a
disease event, you will classify levels of a novel emerging respiratory disease
(NERD). Your group will read posts from the NERD Newsfeed. You will observe how
NERD spreads, starting with reports of 44 initial cases in the fictional country of
Rocona. Using the posts, you will create a timeline of events and then decide when
NERD should be declared a pandemic.
Remember by declaring a pandemic, international cooperation can begin; however, if
you declare it too early, too much time and resources may be spent unnecessarily.
You must be able to explain why you made your decision using evidence from the
timeline.
1 Hand out the individual NERD Newsfeed Posts to each group. Hand out a NERD Timeline to
eac
h student. Provide the optional NERD Factsheet to each group for additional reference.
2 As a class, choose and read one NERD Newsfeed Post aloud. Demonstrate how to record
relevant information (e.g., location, number of cases, type of spread) appropriately on the NERD
Timeline. See t
he NERD Timeline: Answer Key for reference.
For an additional challenge, students can create their timeline starting with a blank sheet of
paper.
3 After completing the first card together, instruct groups to continue reading the NERD
N
ewsfeed Posts, one at a time, marking information on the timeline as demonstrated.
4 Ask for volunteers to help create the classroom version of the NERD outbreak timeline on the
w
all or board.
5 Hand out a NERD Pandemic Label Card to each group. Have groups discuss at which point in
t
ime they believe NERD should be declared a pandemic and why. Instruct them to mark their
groups’ timeline with a “P” and reference the newsfeed posts to determine the exact date they
chose. Remind them that they will need to use evidence to justify their answer.
6 Ask for a volunteer from each group to place their group’s completed NERD Pandemic Label
Ca
rd on the classroom timeline to indicated when their group believes NERD should be
declared a pandemic.
7 As a class, review the classroom version of the NERD timeline and discuss when groups
bel
ieved NERD should be declared a pandemic and why.
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Class discussion (10 minutes)
Why is it that a disease may be categorized differently in different locations? (e.g., malaria is
endemic in many countries, but a single local case must be reported immediately in Iowa,
United States).
Do all diseases become pandemi
cs? Why or why not?
Why might a novel
virus be more likely to cause a pandemic level of disease than a virus that is
not novel?
Definitions
Case: A single instance of disease, injury, or other health condition that meets selected criteria of
clinical and laboratory findings and for person, place and time.
Cluster: A group of cases of the same general health problem that occur in a limited geographical
area without regard to the expected levels.
Endemic: The constant amount of a specific disease that is usually present in a geographic
location, like a state or country.
Epidemic: Similar to an outbreak, but with a larger number of cases or occurring over a greater
area or both.
Epidemiology: The study of disease and other health outcomes, their occurrence and causes in a
population, and the application of this study to control health problems.
Expected level (baseline): An observed amount of disease that is usually present in a community
or geographic location, like a state or country, known through historical counts or public health
surveillance, and often used for comparison in identifying outbreaks or measuring the effectiveness
of public health actions.
Novel virus: A virus that has not been seen before or is a virus that is known but has not infected
humans before.
Outbreak: A higher number of cases than expected in an area within a certain time period.
Pandemic: Similar to epidemic, but has spread over several countries or continents, usually
affecting a large number of people.
For more vocabulary, visit: https://www.cdc.gov/scienceambassador/nerdacademy/
glossary.html.
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Extension ideas
Share the text of the World Health Organization’s (WHO) decision to declare COVID-19 a
pandemic on March 11, 2020: https://www.who.int/director-general/speeches/detail/who-
director-general-s-opening-remarks-at-the-media-briefing-on-covid-19---11-march-2020.
Discuss the criteria WHO used to make that decision and the implications for the rest of the
world.
Read WHO’s global influenza preparedness plan and how influenza pandemics are classified in
six different phases with overarching public health goals:
https://www.who.int/csr/resources/publications/influenza/WHO_CDS_CSR_GIP_2005_5.p
df.
Read “The elusive definition of pandemic influenza” by Peter Doshi:
https://www.who.int/bulletin/volumes/89/7/11-086173.pdf. In June 2009,
WHO declared
H1N1 a pandemic.
Governments
throughout the
world mounted a large
and costly response to
the H1N1 influenza outbreak, however the outbreak had far less consequences than predicted.
Discuss how this controversy might have impacted WHO’s decision to declare COVID-19 a
pandemic in 2020.
Debate if you believe COVID-19, which was declared a worldwide pandemic in March 2020, will
become endemic.
Consider
this news article to help frame your argument:
https://www.usatoday.com/story/news/health/2021/02/17/covid-19-likely-become-
endemic-experts-say-heres-what-means/4487953001/.
Assign students to research the history and create timelines of past pandemics. Use the CDC
website on flu pandemics as a resource: https://www.cdc.gov/flu/pandemic-
resources/basics/past-pandemics.html.
Explore more about malaria, it’s connection to the origins of the CDC, an d how, by 1951,
malaria was considered eliminated from the United States:
https://www.cdc.gov/malaria/about/history/index.html. Continue exploring current
interventions to reduce the number of malaria-related cases and deaths worldwide:
https://www.cdc.gov/malaria/malaria_worldwide/reduction/index.html.
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Resources
CDC Resources
Introduction to Public Health (PH 101 Series)
https://www.cdc.gov/publichealth101/public-health.html
Introduction to Epidemiology
https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section1.html
What is Epidemiology?
https://www.cdc.gov/careerpaths/k12teacherroadmap/epidemiology.html
Epidemic Disease Occurrence (Principles of Epi Lesson 1, Section 11)
https://www.cdc.gov/csels/dsepd/ss1978/lesson1/section11.html
Identifying the Source of the Outbreak
https://www.cdc.gov/coronavirus/2019-ncov/cases-updates/about-
epidemiology/identifying-source-outbreak.html
COVID-19 Frequently Asked Questions
https://www.cdc.gov/coronavirus/2019-ncov/faq.html
The CDC NERD Academy curriculum was developed by the Centers for Disease Control and
Prevention’s (CDC’s) Science Ambassador Fellowship (SAF) program with input from STEM
teachers and public health experts. Support for the curriculum is made possible through a
partnership between the CDC Foundation and CDC. Videos for the curriculum were developed and
produced by Osmosis.
Disclaimer: NERD (novel emerging respiratory disease) is a fictional disease created for this
curriculum. NERD etiology, data, events, and information presented in the CDC NERD Academy
curriculum are loosely based on the understanding of COVID-19 prior to a vaccine becoming
available. Some details have been generalized for educational purposes.
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Knowledge Check: Level of Disease
Directions: After watching the “What exactly is a pandemic?” video (12:39 minutes), answer the
following questions.
1 Which of the following best explains an individual’s health?
a. Physical state
b. Mental state
c. Social well-being
d. All of the above
2 Determine if the following statements about public health are true or false.
True False
Fill in the blank
Example
An individual's health is affected by their genetics and environment.
A person who is sick would be treated by an epidemiologist.
Public health focuses on the health of groups or communities of
people.
Epidemiologists only deal with infectious disease.
An infectious agent that has been newly identified is called novel.
3 Order the following terms from the smallest (1) to largest (4) level of disease occurrence.
Epidemic Outbreak Pandemic Cluster
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Knowledge Check: Answer Key
Directions: After watching the “What exactly is a pandemic?” video (12:39 minutes), answer the
following questions.
1 Which of the following best explains an individual’s health?
a. Physical state
b. Mental state
c. Social well-being
d. All of the above (Correct answer)
2 Determine if the following statements about public health are true or false.
True False
Fill in the blank
Example
An individual's health is affected by their genetics and environment.
True
False
A person who is sick would be treated by an epidemiologist.
True
Public health focuses on the health of groups or communities
of people.
False
Epidemiologists only deal with infectious disease.
True
An infectious agent that has been newly identified is called novel.
3 Order the following terms from the smallest (1) to largest (4) level of disease occurrence.
Epidemic Outbreak Pandemic Cluster
3 2 4 1
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Career Spotlight
CDC NERD Academy
Epidemiologist
An epidemiologist, also known as a disease detective, investigates the causes of diseases,
how diseases are spread, and how diseases can be prevented or controlled. During an
outbreak, epidemiologists collect and analyze information about who is sick, when they
became sick, and exposures they may have had before becoming sick to determine where,
when, and how each person may have become infected. Then, they translate this information
into recommendations for prevention and control measures.
Meet Ezra,
an epidemiologist
a wide range of public health
professionals at the local, state, and federal levels, including other
epidemiologists, hospital and health department staff, data
managers, biostatisticians, laboratory scientists, health educators,
communication specialists, policy makers, and animal health
personnel (like veterinarians).
Who do they work with?
Epidemiologists collaborate with
Where do they work?
Epidemiologists may work in local, state, federal, and international
public health agencies; hospitals; universities; and anywhere an
investigation requires their detective skills.
What skills do they use?
Knowledge of descriptive and analytic epidemiology, ability to
analyze data and interpret findings, ability to think critically and
problem solve, strong m ath skills, ability to communicate clearly to
different audiences, willingness to work in different environments,
and ability to work collaboratively with other experts and public
health partners.
What qualifications do they need?
Epidemiologists often have a bachelor’s degree in any science
field, such as nutrition, public health, or biology, and a master’s or
doctoral degree in epidemiology. Undergraduate degrees in
mathematics (especially statistics) or the social sciences (such as
geography or sociology) are also useful.
Module 1 Career Spotlight
NERD Factsheet
CDC NERD Academy
What is NERD?
NERD is a fictional novel emerging respiratory disease caused by a virus that can spread
from person to person. NERD symptoms can range from mild (or no symptoms) to severe
illness and death.
Who can get NERD?
People of any age can get NERD, even
healthy young adults and children.
People who are older or have certain
underl
ying medical conditions are at
higher risk of getting very sick from
NERD.
Other groups may be at higher risk for
g
etting NERD or having more severe
illness.
What are the symptoms of NERD?
Symptoms may appear 2–14 days after
exposure to the virus. People with these
symptoms may have NERD:
Fever or chills
C
ough
Shortness of breath or difficulty breathing
Fatigue
Muscle or body aches
Headache
New loss of taste or smell
S
ore throat
Congestion or runny nose
Nausea or vomiting
Diarrhea
What do I do if I have symptoms?
Stay home except to seek medical care.
Separate yourself from other people.
Get tested. If you test positive, tell your
c
lose contacts that they may have been
exposed to NERD.
You can be with others after at least 10
days
since your symptoms first appeared
and at least 24 hours with no fever.
Be aware of the signs of severe
disease, including trouble
breathing, pain or pressure in the
chest, confusion, or trouble
waking or staying awake. If
someone is showing any of these
signs, seek emergency medical
care immediately.
NERD Factsheet
How does NERD spread?
NERD most commonly spreads during direct, close contact:
When people have direct contact with a person with NERD.
When a person with NERD releases respirat
ory droplets when
they cough, sneeze, sing, talk, or breathe, and these droplets
are inhaled by another person who is physically near (within 6
feet).
NERD sometimes s
preads through airborne transmission,
especially indoors:
When a person with NERD breathes heavily — such as when ex
ercising, singing, or shouting —
they can produce more respiratory droplets that can linger in the air for minutes to hours.
NERD is less commonly spread through contact with contaminated surfaces.
When a person touches a s
urface or object with the virus on it and then touches their mouth,
nose, or eyes.
What if I have been in close contact with someone with NERD?
Close contact is defined as being within 6 feet of a NERD-positive individual for a total of 15
minutes or more.
Separate yourself from other people. A person infected with NERD can spread the virus starting
48 hours, o
r 2 days, before the person feels any symptoms or tests positive.
Watch for symptoms until 14 days after exposure.
If you do not
have symptoms, you can be with others 14 days after your last contact with
someone wi
th NERD.
If you have symptoms, you can be with others after at least 10 days since your symptoms first
appeared and at l
east 24 hours with no fever.
Get tested. If you test positive and have no symptoms, you can be with others after 10 days
have passed s
ince the date you had your positive test.
Three important ways to slow the spread
1 Wear a mask to protect yourself and others and stop the spread of NERD.
2 Stay at least 6 feet (about 2 arm lengths) from others who don’t live with you.
3 Avoid crowds. The more people you are in contact with, the more likely you are to be exposed
to NERD.
CDC NERD Academy
www.cdc.gov/scienceambassador/nerdacademy
Level of Disease Event Cards
Event 1
Time
March 2014–February 2016
Person
15,261 laboratory-confirmed cases
Place
Guinea, Sierra Leone, and Liberia
Signs and symptoms
Fever, severe headache, muscle pain,
weakness, fatigue, diarrhea, vomiting,
abdominal (stomach) pain, and unexplained
hemorrhage (bleeding or bruising)
Figure 1: Total number of cases, March 2014
–
February 2016. On this map of Guinea, Sierra
Leone, and Liberia total cases categories are 1–5
cases, 6–20 cases, 21–100 cases, 101–500 cases,
501–4,000 cases, and no cases reported.
Event 2
Time
January 4, 2015–April 2, 2015
Person
125 confirmed cases
Place
8 U.S. states, mostly California (n = 110
cases)
Signs and symptoms
Rash lasting >3 days, fever, cough, coryza
(runny nose), and conjunctivitis (pink eye)
Non-Disney import-associated (n = 43)
Disney import-associated (n = 111)
Unknown source (n = 5)
Figure 2: Number of reported cases (n = 159) by
infection source, state, and county. Forty-three cases
are non-Disney import-associated, 111 are Disney
import-associated and 5 are of unknown source. On
this map of the United States, cases are shown in 8
U.S. states with most of the cases in southern
California (n = 110).
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Event 3
Time
1998 to present day
Person
About 10,000 cases reported each year in the
United States
Place
Primarily Southwest United States
Signs and symptoms
Tiredness, cough, fever, shortness of breath,
headache, muscle aches or joint pain, and
rash on upper body or legs; can cause
chronic pneumonia in severe cases
Figure 3: Areas at risk for exposure in the United
States. On this map of the United States, most areas
at risk for exposure are in the southwestern part of
the United States.
Event 4
Time
April 2009–April 2010
Person
18,631 laboratory-confirmed cases, though
between 123,000 and 203,000 were
estimated globally for the last 9 months of
2009
Place
168 countries
Signs and symptoms
Fever or feverish chills, cough, sore throat,
runny or stuffy nose, muscle or body aches,
headache, fatigue, vomiting (in children), and
diarrhea (in children)
Mortality rates per 100,000
0–1 1–1.5 1.5–2 2–2.5 2.5–3 3–3.5 3.5–4 4+
Figure 4: Projected worldwide mortality rates per
100,000 persons (all ages). This world map shows
rates per 100,000 by country, including the United
States (2–2.5), Canada (3–3.5), South American
countries (2.5–4+), African countries (1.5–4+),
European countries (0–2.5), Asian countries (1.5–4+)
and Australia (0–1).
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Level of disease by percent
No <10% 10%– 15%– 20%– 25%– >30%
Data 14% 19% 24% 29%
Figure 5: Level of disease over time in the United
States. On the map for year 1990, states show a
level of disease of <10%, 10%–14%, or No Data. On
the map for year 2000, states show a level of
disease of 10%–14%, 15%–19% or 20%–24%. On
the map for year 2010, states show a level of
disease of 20%–24%, 25%–29%, or >30%.
Event 5
Time
1990–Present day
Person
36.5% Adults (aged 18+ years)
17.0% Children (aged 2–17 years)
Place
Widespread, United States
Signs and symptoms
Body Mass Index (BMI) ≥30.0 adults, BMI
≥95
th
percentile in children
Event 6
Time
Present day
Person
84,000–170,000 severe cases annually
Place
West, East and Central Africa
Signs and symptoms
Fever and feverish chills, severe headache,
back pain, general body aches, nausea, and
vomiting; in severe cases, high fever,
jaundice, bleeding, and multiple organ failure
Figure 6: Areas with risk of transmission in Africa. On
this map of Africa, countries where vaccinations are
recommended are mostly in central Africa, countries
where vaccinations are generally not recommended
are mostly in eastern Africa, and countries where
vaccinations are not recommended are in north and
south Africa.
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Event 7
Time
March 31, 2019–February 15, 2020
Person
2,807 hospitalized cases or deaths
Place
United States
Signs and symptoms
Pneumonia-like symptoms, coughing, chest
pain, and shortness of breath
Number of hospitalized patients or deaths
0 1–9 10–49 50–99 100–
149
150– 200–
199 249
Figure 7: Number of hospitalized patients or deaths
per state as of February 18, 2020. On this map of the
United States, most states have 0–99 cases, some
states show 100–149 cases, two states show 150–
199 cases (New York and California), and two states
show 200–249 cases (Texas and Illinois).
Event 8
Time
November 2015–January 2016
Person
55 cases
Place
11 U.S. states, mostly Washington (n = 27)
and Oregon (n = 13)
Signs and symptoms
Stomach cramps, diarrhea (often bloody),
and fever
Number of people infected
1 2–12 13–26 27–30
Figure 8: People infected, by state of residence, as
of January 27, 2016 (n = 55). On this map of the
United States, there are five states with 1 case
(Delaware, Illinois, Kentucky, Maryland, New York),
4 states with 2–12 cases (California, Minnesota,
Ohio, Pennsylvania), one state with 13–26 cases
(Oregon), and one state with 27–30 cases
(Washington).
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Event
Level of
Justification
Disease
disease
1
2
3
Level of Disease Classification
Directions: Review the event cards. Classify each event by level of disease occurrence (endemic,
outbreak, epidemic, pandemic). Record your answers below and justify your answer. Brainstorm the
disease that could be represented by each event.
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Level of Disease Classification: Answer Key
Directions: Review the event cards. Classify each event by level of disease occurrence (endemic,
outbreak, epidemic, pandemic). Record your answers below and justify your answer. Brainstorm the
disease that could be represented by each event.
Event
Level of
Justification
disease
Disease
1
Epidemic
This event card is based on the 2014–2016 Ebola
epidemic in West Africa. More than the expected
number of cases occurred in multiple countries.
Overall, it is considered an epidemic because it
was primarily contained in the region of West
Africa.
Ebola
2
Outbreak
This event card is based on a 2015 multistate
measles outbreak. It is considered an outbreak
because it is linked to a single case at an
amusement park in California.
Measles
3
Endemic
This event card is based on valley fever, which
is caused by a fungus that lives in the soil. It is
considered endemic because about 10,000
cases are expected to be reported in the United
States each year, mostly from Arizona and
California.
Valley Fever
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Event
Level of
Justification
disease
Disease
4
Pandemic
This event card is based on the 2009–2010 H1N1
influenza pandemic. It was declared a worldwide
pandemic on June 11, 2009. At the time, more
than 70 countries had reported cases of 2009
H1N1 infection, and community level outbreaks
of 2009 H1N1 were ongoing in multiple parts of
the world.
H1N1
Influenza
5
Epidemic
This event card is based on obesity levels in the
United States during 1990–present. In 1999,
obesity was declared an epidemic because of
the growing rates of obesity in the United States
across all ages and racial groups. (Although this
is more an issue of word choice since a true
epidemic is an event and not a trend).
Obesity
6
Endemic
This event card is based on yellow fever in Sub-
Saharan Africa. It is considered endemic
because there are about 84,000–170,000 severe
cases annually.
Yellow Fever
7
Outbreak
This event card is based on a 2019–2020
outbreak of EVALI (e-cigarette, or vaping,
product use-associated lung injury) in the
United States. A rapid increase in cases led to a
total of 2,807 hospitalizations and deaths
reported from 50 states, the District of Columbia,
and two U.S. territories (Puerto Rico and the U.S.
Virgin Islands) during March 31, 2019–February
15, 2020.
EVALI (e-
cigarette or
vaping
product use-
associated
lung injury)
8
Outbreak
This event card is based on the initial, larger
outbreak of Shiga toxin-producing Escherichia
coli O26 (STEC O26) infections linked to food
served at a chain of fast casual Mexican
restaurants in 2015. Although 55 cases of
infection occurred across 11 states, the same
STEC O26 strain was isolated in each case
suggesting that a common food item distributed
to multiple restaurants was the likely cause.
Shiga toxin-
producing
Escherichia
coli O26
(STEC O26)
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Resources
Event 1
Learn more at: https://www.cdc.gov/vhf/ebola/symptoms/index.html. The image referenced
on the event card can be found at: https://www.cdc.gov/vhf/ebola/history/2014-2016-
outbreak/distribution-map.html
Event 2
Learn m
ore at: https://www.cdc.gov/mmwr/preview/mmwrhtml/mm6414a1.htm. The image
referenced on the event card can be found at that link.
Event 3
Learn m
ore at: https://www.cdc.gov/fungal/features/valley-fever.html. The image referenced
on the event card can be found at that link.
Event 4:
Learn m
ore at https://www.cdc.gov/h1n1flu/cdcresponse.htm. The image referenced on the
event card can be found at: https://www.ncbi.nlm.nih.gov/pubmed/24302890.
Event 5
Learn m
ore at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2608606/?page=1 and
https://www.cdc.gov/obesity/index.html. The image referenced on the event card can be
found at: https://www.cdc.gov/obesity/data/prevalence-maps.html.
Event 6
Learn m
ore at: https://www.cdc.gov/yellowfever/index.html. The image referenced on the
event card can be found at: https://www.cdc.gov/yellowfever/maps/africa.html.
Event 7
Learn m
ore at: https://www.cdc.gov/tobacco/basic_information/e-cigarettes/severe-lung-
disease.html. The image referenced on the event card can be found at:
https://www.cdc.gov/tobacco/basic_information/e-cigarettes/severe-lung-
disease.html#map-cases.
Event 8
Learn m
ore at: https://www.cdc.gov/ecoli/2015/o26-11-15/index.html. The image referenced
on the event card can be found at: https://www.cdc.gov/ecoli/2015/o26-11-15/map.html.
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NERD Newsfeed Posts
Nerd Tracker
@CDC_NERDNews
January 3
Nerd Tracker
@CDC_NERDNews
January 20
Nerd Tracker
@CDC_NERDNews
January 21
44 cases of a novel
emerging respiratory
disease reported to the
World Health
Organization in the
country of Rocona.
Imported cases of a
novel emerging
respiratory disease are
confirmed: 2 in Thailand,
1 in Japan, and 1 in
South Korea. All patients
recently travelled to
Rocona. To date, cases
are confined to Asia.
This novel emerging
respiratory disease is
named NERD. United
States reports first
travel-related case of
NERD in the state of
Washington. The patient
recently returned from
the country of Rocona.
Nerd Tracker
@CDC_NERDNews
January 30
Nerd Tracker
@CDC_NERDNews
February 15
Nerd Tracker
@CDC_NERDNews
February 22
CDC confirms first
human-to-human spread
in U.S. Chicago, IL,
woman infected her
husband with NERD.
Wife recently returned
from overseas travel.
Egypt reports first
confirmed NERD case
on the continent of
Africa.
Of the 346 confirmed
NERD cases in South
Korea, 80% were related
to two nearby facilities.
169 (48.8%) cases tied
to a church and 108
(31.2%) to a nearby
hospital.
Nerd Tracker
@CDC_NERDNews
March 7
Nerd Tracker
@CDC_NERDNews
March 9
Nerd Tracker
@CDC_NERDNews
March 11
CDC confirms
community transmission
of NERD occurred at two
family gatherings in
Chicago, IL. The 16
confirmed cases
included 3 deaths.
Italy announces travel
restrictions for over 60
million people as the
number of NERD cases
climbs to 9,172 with
1,598 deaths.
NERD outbreaks have
been reported in just
over half (58%) of
countries worldwide with
118,319 total cases
(approximately .0015%
of the world’s
population).
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Nerd Tracker
@CDC_NERDNews
March 17
Nerd Tracker
@CDC_NERDNews
March 26
Nerd Tracker
@CDC_NERDNews
April 4
High NERD attack rate
after exposure during
choir practice in Skagit
County, WA. Of 61 in
attendance, 32
confirmed & 20 probable
cases occurred. In total,
3 are hospitalized and 2
dead.
Canada reports 1,670
new cases of NERD
bringing the total cases
for the country to 3,409
with 35 deaths.
The number of
confirmed NERD cases
reported tops one million
worldwide with over
56,000 deaths.
Nerd Tracker
@CDC_NERDNews
April 27
Nerd Tracker
@CDC_NERDNews
April 28
Nerd Tracker
@CDC_NERDNews
May 11
NERD among workers in
meat and poultry
processing plants
reported in 19 U.S.
states. Among
approximately 130,000
workers at these
facilities, 4,913 cases
and 20 deaths occurred.
U.S. reports NERD tops
one million cases. U.S.
accounts for 1/3 of all
reported cases
worldwide.
Number of NERD cases
tops 4 million worldwide
as reported in 181
countries (93%) on 6 of
the 7 continents.
Nerd Tracker
@CDC_NERDNews
June 11
Nerd Tracker
@CDC_NERDNews
June 16
Nerd Tracker
@CDC_NERDNews
June 27
NERD cases increasing
in rural U.S.
communities. In total, 30
persons with laboratory-
confirmed NERD
attended Amish religious
and social gatherings in
the Ohio community.
Transmission of NERD
associated with sports.
In total 13 laboratory-
confirmed cases linked
to recreational hockey
game in Florida.
Among 344 attendees of
an overnight camp in
Ohio, 260 (76%) tested
positive for NERD
despite efforts by camp
officials to follow
recommended
prevention strategies.
Module 1 Defining a pandemic CDC NERD Academy Page | 24
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CDC NERD AcademyCDC NERD Academy
NERD Timeline
Directions: As a group, read each post on the NERD Newsfeed, one at a time. Mark information such as # of cases, location and other
important details on the timeline below. When all post details have been recorded, decide when NERD should be declared a pandemic
by marking the timeline with a “P”.
January February March April May June
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NERD Timeline: Answer Key
Directions: As a group, read each post on the NERD Newsfeed, one at a time. Mark information such as # of cases, location and other
important details on the timeline below. When all post details have been recorded, decide when NERD should be declared a pandemic
by marking the timeline with a “P”.
Answer: The timeline is provided below. NERD could be declared a pandemic in March after 118,319 cases in 58% of countries
January February March April May June
worldwide were reported.
44 cases in Rocona
4 cases in
Japan, Thailand, SK
(Asia)—imported
2 cases in
Illinois (US)—
first person-to-
person cases
346 cases
South Korea—
80% related to 2
facilities
9,172 cases in Italy—
travel ban starts
32 cases
(20 probable) in
Washington
(US)—high
attack rate
1,000,000 cases
worldwide—
56,000 dead
1,000,000
cases in the
United States
30 cases in
Ohio (US)—
rural transmission
260 cases in
Georgia
(US)—youth
transmission
1 case in Washington
(US)—imported
1 case in
Egypt (Africa)
16 cases in Illinois
(US) —community
transmission
118,319 cases in
58% countries
worldwide
3,409 cases in
Canada
4,913 cases in
19 states (US) —
industry specific
4,000,000 cases in
93% of countries worldwide
6 of 7 continents
13 cases in Florida (US)—
sport specific
P
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Image Description: Timeline of events starting from January to June. January Events: 44 cases in
Rocona, 1 Case in Washington (US)-Imported, 2 Cases in Illinois (US)-first person-to-person cases,
and 4 cases in Japan, Thailand, SK (Asia)-Imported. February Events: 1 case in Egypt (Africa), and
346 cases South Korea-80% related to 2 facilities. March events: 16 cases in Illinois (US)-
community transmission, 3,409 cases in Canada, 32 cases (20 probable) in Washington (US)-high
risk attack rate, 118,319 cases in 58%of countries world wide, and 9,172 cases in Italy-travel ban
starts. April Events: 4,913 cases in 19 states (US)-industry specific, 1,000,000 cases in United
States, and 1,000,000 cases worldwide-56,000 dead. May Events: 4,000,000 cases in 93% of
countries worldwide 6 of 7 continents, and 30 cases in Ohio (US)-rural transmission. June Events:
13 cases in Florida (US)-sport specific, and 260 cases in Georgia (US)-youth transmission.
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P
NERD Pandemic Declaration
Group name
Date
Justification
P
NERD Pandemic Declaration
Group name
Date
Justification
P
NERD Pandemic Declaration
Group name
Date
Justification
P
NERD Pandemic Declaration
Group name
Date
Justification
P
NERD Pandemic Declaration
P
NERD Pandemic Declaration
Group name
Date
Justification
Group name
Date
Justification
NERD Pandemic Label Cards
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