In my classroom: Mathematical modeling of Influenza spread (and comparison to Coronavirus COVID-19)

Every biology classroom is likely teeming with discussions about COVID-19. This offers a unique opportunity to share real-time data and situations with students. Each day brings new developments in this world public health crisis. How are the epidemiologists working to temper the spread?

This week, I adapted a lesson plan which I co-developed for high school students as part of the Science Fellowship program in 2014 (1). The plan is “Have You Herd” and is available for free, in its entirety, on the CDC website. Here is the pdf link: which is also listed in references below (2). The lesson has links to NGSS standards on page 14 of the pdf (page 11 if printed hardcopy of lesson).

SEMANTICS NOTE: The novel coronavirus, which is central to the current outbreak, is notated as SARS-CoV2. This virus causes coronavirus disease, identified in 2019, which is notated COVID-19 (3).

Time estimate: 90 minutes-ish, depending on length of discussion and if you assign the pre-lab the night before or have students complete in class.

Why use an influenza lesson to teach about COVID-19? From the CDC website: “the newly emerged coronavirus disease 2019 (COVID-19) is a respiratory disease that seems to be spreading much like flu. Guidance and tools developed for pandemic influenza planning and preparedness can serve as appropriate resources for health departments in the event the current COVID-19 outbreak triggers a pandemic” (4).

Learning Objectives:

After completing this lesson, students should be able to (coronavirus addendums are in parentheses):
• employ mathematical models for influenza (SARS-CoV2) outbreak scenarios to calculate measures of disease spread and intervention effectiveness.
• synthesize effects of physical (e.g., social distancing or non-pharmaceutical interventions) and medical (e.g., vaccines) countermeasures for influenza outbreak scenarios. What are COVID-19 physical countermeasures which can be employed (especially since a vaccine is currently unavailable)?
• identify public health countermeasures that restrict the spread of an influenza (SARS-CoV2) outbreak.
• IF PART 2 OF LESSON IS USED: explain the importance of vaccinations and monitoring cases of infectious diseases. Since there is currently no vaccine is available for COVID-19, this part of the lesson really only works if using only influenza as written. You can discuss that there is a race to create a vaccine to SARS-CoV2.

Overview: I taught the lesson plan as it was written, but added the following components:

  • Opening: Make it clear to students that this lab is about influenza, however when appropriate, COVID-19 data will be discussed as a comparison.
  • Prelab: Assigned students to make a chart to compare flu to COVID-19. I did this ad hoc, but you could take the basic chart from Appendix 1A and have the students make a second column for COVID-19. I especially like the “misconceptions” line – they could list anything they heard early on about COVID-19. Note that at this time, seasonality of SARS-CoV2 is unknown, so that part of the chart students would leave blank. Another column of “cause” would be helpful to distinguish the difference between COVID-19 to SARS-CoV2 (as noted in the semantics note/paragraph 3, above) versus. influenza to influenza virus A, B or C.
  • Worksheet 1: Note that there are three different demographic scenarios to this activity, A-C. One-third of your class should each be given their corresponding version of Worksheet 1. For reference, A = urban/dense population; B = suburban/moderate population density; C= rural/low population density. Wetlab opening – Perform as written in lesson. Point out that the wetlab simulation of rapid influenza test is a nasopharyngeal swab (long Q-tip thing which makes you gag – they will relate). The CDC SARS-CoV2 test kit uses a similar collection method, plus may also collect sputum (6). Tests are described on the CDC website (6). Discussion questions & R0 calculations – Calculate as written. I like to work through this worksheet as a whole class but allowing each group (A-C) to work together to perform their calculations and double check each other. Then we discuss questions as a class. Helpful R0 information is listed in references below (7). Something which struck me as this lesson was developed was that although small towns have less people, therefore less opportunity for interactions with an infected person, the folks an infected person encounters is more likely to be someone they know (closer contact). It is more likely they will hug, shake hands, hug, etc. if they know the person. Thus, your students will see that the scenario C is not too far off from R0 of scenario A. As you conclude the calculations (discussion questions 1-9), compare the various R0 for your three different populations to the R0 value for COVID-19. One source that I found reported R0 for COVID-19 to be anywhere from 1.4 to 4.08 (8). I’ve seen the number in various places and, situationally, it varies, which makes sense. Examples to discuss are a cruise ship vs. various providences in China. Check out the description in that source (8) with a nice comparison of R0 for different diseases. If you are not familiar with R0 and are Googling around, note that it is different than RE (effective reproduction number). RE is addressed in Worksheet 2.
  • Worksheet 2: Although optional for the purpose of COVID-19 knowledge (because there currently isn’t a vaccine), I went ahead and had the students work through Worksheet 2 where they calculate herd immunity threshold (Ic) and the critical vaccination level (Vc). We discussed the effective reproduction number (RE) of influenza and who is appearing to be susceptible to COVID-19. CDC has a rapidly changing risk assessment description available on their website (9).
  • Assessment (Appendix 4A): I love the figure of genetic evolution of influenza virus H7N9. It really shows how genetic shift occurred in a possible bird/poultry market to generate a novel virus which affected humans in 2013 China. Relate this to the source and spread of SARS-CoV2 (10). Make sure your students know what zoonotic diseases/zoonoses are! Merck Manual online (source 3) is my go-to for animal related information (I teach a veterinary medicine course). Search “zoonotic diseases” on Merck Manual or any credible source.


  • Worksheet 1, before question 3, have actress Kate Winslet from 2011 movie, Contagion, introduce the concept of R0 in about 10 seconds:
  • Do some epidemiological studies. There is a great module on the CDC website, complete with slides for teacher use (11).
  • Have students choose a section to research from the JAMA article, Characteristics of and Important Lessons from the Coronavirus Disease 2019 (COVID-19) Outbreak in China (12). Then, report back to the whole class in jigsaw style.
  • Deconstruct the epidemic curve (“epi curve”) of that same article (12).
  • Show some video clips about herd immunity (13 & 14), especially if you had the students complete Worksheet 2.
  • Have students compare COVID-19 to MERS and SARS. Compare and contrast. Ask them to look into the zoonotic origin. What are zoonoses/zoonotic diseases (15 and 3)?
  • Some more fabulous resources to share with your students in references (16 & 17). Check in back in with those resources periodically as a class.


  1. Science Fellowship program:
  2. “Have You Herd” lesson plan:
  3. COVID-19 vs. SARS-CoV2, and description of coronaviruses:,-mers,-and-sars
  4. Why use an influenza lesson to teach about COVID-19? How is the United States preparing for a pandemic?
  5. Nasopharengeal samples for COVID-19 testing, described in “Specimen Type and Priority” section at
  6. Tests for COVID-19 described at
  7. R0 information – 9:00 min video for the teacher if you’ve never calculated “R-naught” AKA “basic reproductive number”:
  8. R0 for COVID-19:
  9. COVID-19 CDC Risk Assessment:
  10. Source and spread of SARS-CoV2:
  11. Introduction to Epidemiology:
  12. JAMA Network article synthesizing CDC data:
  13. Herd immunity –  3:31 min video:
  14. Herd immunity – 2:17 min video:
  15. Zoonotic Diseases/Zoonoses – why are they so deadly?
  16. Current situation report, compiled by the World Health Organization:
  17. Rolling updates on Coronavirus from World Health Organization:

In My Classroom: POOP LAB! (AKA Fecal Floats/intestinal parasite lab)

A lab favorite in my classroom is the Poop Lab. I teach a Veterinary Medicine course for high school juniors and seniors (life science credit). Parasitology is one of the class foci (is it because I LOVE the gross factor? Probably). If you cover parasites, zoology or even zoonotic diseases, this lab is a must do! YOU DO NOT NEED A CENTRIFUGE to do this lab. Alternative instructions are written on the student lab.

Goal of the lab:  
Perform a fecal float analysis with sample from a  family pet.  Determine if that pet has possible intestinal parasites.

Rationale: Determining if the students’ own pet has a parasite is extremely  engaging (or the neighbor’s pet).  Plus, it’s a darn good microscopy 
exercise on identifying what is significant or not (hair or air bubble).

Homework the night before: I send students home with a disposable fecal collection chamber (1). If you don’t have those, a Ziploc or other small disposable container will suffice (the thicker the better stink barrier it will be). I also give them the option of grabbing a set of exam gloves in case they are horrified by the thought of poo grazing their hand. Students are instructed to collect 2-5 cc of FRESH ANIMAL poo from their pet at home (or ask a neighbor for use of their yard/litter box/etc.). No human poo accepted. ANY pet will work. Iguana, dog, chicken, horse, cat, goat, hamster, chinchilla, etc.

Such a memorable lab…

I’ve usually emailed home to give the parents a heads up that bringing an ANIMAL poop sample to school is legit (no worries about stuffing it someone else’s locker as a prank). FRESH IS BEST so collection morning of the lab preferred, but most animals don’t poop on command. If they have an evening pooping animal, it’s OK to collect the night before, but should be refrigerated overnight (um, this is again where a parental heads up comes in handy – probably won’t want container of poop in the family fridge). If poop is banned from the kitchen, a lunch box with freezy pack. If they use ice to keep it cool, make sure the water doesn’t leak into the poo container. That is a lunch box sludge that is best avoided.

Lab Day: If this is not your students’ first time using a microscope, this lab can be completed in a 45 minute session, including cleanup. This is possible because I prefer to maximize the use of disposable items. After the first student spills a test tube of sugared poo slurry and you see how difficult it is to clean up the sticky mess, you’ll thank me for that little tidbit of wisdom. Try asking your local Sonic, etc. for a donation of a box of smoothie straws (AKA disposable scoopulas) to mentally scar students’ future enjoyment of smoothies following this lab.

Here’s the one-page handout of instructions that I give each student:

Who wouldn’t be all smiles after retrieving the poo slurry from the centrifuge?

I built tips into the instructions, so give it a good read before trying with students. You will need a comparison chart [(2) or extension activity described below BEFORE this lab] so that if students find something that looks like a parasitic egg (4), they can try to identify which parasite might be infesting Fluffy’s intestines.
You will need to order or mix up a sugar solution ahead of time (3). Wards has a “Fecal Slide Analysis Activity” which boils down to this same lab. I wouldn’t spend the money on it (although I did the first year), unless you like the handy dandy teacher manual (which does have some interesting fun facts – but that’s all I like about it).

How it works:  The parasite eggs (4)  are less dense than the solution.  After centrifuging (or allowing to sit  for a length of time), the eggs float to the top of the tube.  They bind to  the coverslip, allowing us to see the eggs on the scope.  The parasitic  infection can be determined based on the shape/appearance of the eggs on the slide.

IF there is anything suspect, use an identification chart (2) or a scientific based website to try to match the microscope image with known parasite pictures. See additional activity ideas below. Check out this website: I like that towards the bottom, they also identify other items which might be seen on the slides and are no cause for alarm (normal bacterial flora, hairs, air bubbles).

My students have seen green blobs that look like stacked bricks. It’s a hoot for them to try to guess what network type of parasite that might be, only to finally draw the connection between plant cells from Bio I and, “oh yeah, my dog ate grass.”

Strongyles from horse. Image from my class, fall 2018. Note that this slide sat on the scope a little too long so the sugar solution is starting to get sticky under the coverslip. Too much longer and it would have been crystalized.

Three swine whipworm eggs can be seen, approximately diagonal from upper right to lower left. Image from my class, fall 2016. This was considered a low parasitic load and we did not treat the pig sounder at that time.

Note about livestock: It is actually considered normal for a livestock animal to have some parasitic load. This keeps the immune system fighting the parasites instead of treating again and again to the point they become resistant. Instead of a fecal float (like this lab) for diagnosis, a count is performed after isolating possible eggs. A cell count slide is used (sounds like a hemocytometer to me). If 1 cc of fecal matter yields over a certain threshold for that parasite in that animal, then treatment is administered. Don’t ask me the threshold – if you come across any more info about this, please add to the comment section below. Fall 2018, my students found Strongyles (a horse nemotode) in the poo I brought in from one of my horses. I showed the picture to my veterinarian. Although we didn’t quantify, she felt it was probably a low parastitic load and would naturally be kept at bay. I rotate through a different dewormer for my horses every spring and fall. Horse strongyles can’t be passed to my happily horse poop eating hound dogs, so they continue to be clear every time my class looks at their poop.

What to do if evidence of parasite IS found in a pet:
Instruct the student not to panic. Have the student take a photo of the microscope image. It is recommended that he/she share the information with the parent to possibility be passed along to the family veterinarian. The vet while likely ask for a fecal sample or to bring the pet to the clinic for a fresh sample to be taken (via tiny spoon inserted into the anus – very fresh). Some veterinarians might do a version of an ELISA to confirm various parasites. After doing this 10 semesters in our suburban school setting, I have only had one pet fecal sample come out positive (Coccidia). That was a sample collected the morning of class from an abandoned poo pile in the student’s yard. Honestly, the HUNT for parasitic evidence is fun – you really don’t want a positive result. That means the pet *likely* has a parasite.

Coaxing 2-5 cc of horse fecal matter into the collection tube.

Extensions / additional activities pre or post lab:

References to above

If you want the “real thing,” these are two types of fecal collection chambers on the market.

(1) – Ordering info for collection chambers – the “official” fecal collection chambers aren’t needed. A disposable conical lab tube (with lid) would be fine. However, if you want the “real thing,”

(2) – Identification chart: You might be able to obtain some charts through your local veterinarian OR make your students create a chart as a pre-lab (described in extension activities). I have found that Pinterest has several charts, found through a quick Google search (make sure you’re looking at companion animals, not just goat parasites):

(3) – Ordering info for Sheather’s Fecal Float (sugar) Solution – you can mix this up yourself with sucrose and dWater. The exact specific gravity should be 1.27. The solution is described in Dr. Dryden’s article below (Magnesium Sulfate solution can be used instead of sugar, also described in the article). Alternatively, you can order the solution pre-made.

  • Dryden MW, Payne PA, Ridley R, et al. Comparison of common fecal flotation techniques for the recovery of parasite eggs and oocysts. Vet Ther2005;6(1):15-28.

4) – “Eggs” are used generally in this article. Depending on the parasite, students may actually be looking at/for the actual protozoa (Giardia trophozoite), the egg (tapeworm or hookworm oocyte) or cyst (Giardia cyst – tenacious temperature tolerant oocyte manifestation).

(5) – Possible companion animal parasites include: Alaria (intestional flke), Spirometra (taepworm), Paragonimus kellicotti (lung fluke), Platynosomum fastosum (liver fluke), Dipylidium canium (flea tapeworm), Taenia species (tapeworm), Capillaria aerophila (lungworm), Trichuris vulpis (whipworm), Uncinaria stenocephala (hookworm), Ancylostomas species (hookworm), Physaloptera species (stomach worm), Toxascaris lonina (round worm), Toxocara cati (roundworm), Toxocara canis (round worm), Baylisascaris species (racoon roundworm), Strongyloides larvae (threadworm), Giardia trohphozoite, Giardia cyst, Isospara species (Coccidia), or Toxoplasma gondii.

Additional resources:

In My Classroom – #5 (Public Interactions/Real World Experiences for Students)

Welcome to the KABT new blog segment, “In My Classroom”. This is a segment that will post about every two weeks from a different member. In 250 words or less, share one thing that you are currently doing in your classroom. That’s it.

The idea is that we all do cool stuff in our rooms, and to some people there have been cool things so long that it feels like they are old news. In this segment, if you are tagged all you need to do is share something you’ve done in your classroom in the last two weeks. It must be recent, but that’s it. If you are tagged, you’ve got two weeks to post your entry. Who knows… your supposedly mundane idea, lesson, or lab might be exactly what someone else really needs. Keep it brief, keep it honest about the time window, and share it out! Here we go:

20150326_090006This year, I have completely changed how I teach.  An absolute turn-around.

The course that I teach is Veterinary Medicine.  It is taken by high  school juniors and seniors.  Many of my students know they want to pursue a veterinary or vet tech path.  Other students are taking my course to see what is out there; they love animals but are not sure how to weave that love into a future career.   The challenge going into the school year was how to provide meaningful experiences for the students which are rich in content and exploration (I am not a veterinarian).

My approach follows the model which my school uses – community interactions.  Depending on the course you teach, you may not be able to incorporate this model to the full extent, but I believe each classroom could implement a little community interaction for a win-win.  With all of our community interactions, I tweet pictures and quips about our experiences.  This gets the word out about our business partners AND gives us community exposure!

  1. Guest speakers20141203_144128(0)This is the easiest to implement since it does not require buses, permission slips and budget. I used to be afraid? embarrassed? to call someone up to ask them to come speak to my class, feeling like it would be an imposition.  Not anymore!  I have 20140919_140703found folks are very supportive of education; professionals love sharing their passion with students!  I have had veterinarians, vet techs, ranchers, former students who are pre-vet, and even a speaker representing the beef industry.
  2. No farther than your own backyard – Of course your school grounds could be a utopia for teaching, but have you looked at the people there? The nurses in my building have been invaluable a teaching my students skills (intramuscular injections, venipuncture, catheterization).  Have you have talked to your School Resource Officer about speaking to your class?  He/she could lend a wonderful application of biotechnology via crime scene evidence during your unit on DNA.
  3. Not-for-profits as a resource20150114_090433Charitable organizations love to get their message out! Many of them have educational programs already in place. For your class, consider a local food bank during a unit on nutrition or digestion.  What about a visit from a cancer philanthropy during your cell unit or a conservation group during your environmental unit?  The possibilities are endless!  This quarter, my students spend Thursdays at a local horse rescue (  Students are getting HANDS-ON experience working with horses, lending a hand to the owner. We learned shelter medicine AT the animal shelter ( and continue to go their regularly.
  4. Businesses (small, big and everything in between!)20140829_143731 Look into businesses that sell services or products which have an application to your class. For example, I have had a dog trainer come to my class.  We had “BYOD day (bring your own dog)” and had a training session on school grounds.  Another example?  I have built relationships with two large veterinary pharmaceutical companies in my area.  One offers us guest speakers.  The students love asking questions about how they got where they are.  The other company designed a project for my students to work on.  Real world experiences!!
  5. Site visits20150311_090321Transportation (and thus budget) is an issue to taking the students on site visits. All of my students & parents have signed a blanket field trip form allowing them to drive themselves, carpool, or take school transportation.  This has greatly simplified the possibility of seeing what professionals do where they do it!  We have gone to private farms, a dairy, various sizes of cattle ranches, the Zoo and a slaughter/processing facility (wow – we saw the lymph nodes which are an important part of the meat inspection process!).  Where could you go to punctuate what you are learning in the classroom?
  6. Professional societies20140927_112429Something that you teach will a professional society associated with it.  Contact them.  See if there are speakers, conferences or field trips your students could attend.  You are spreading the word about what they do to a potential market (your students).  For example, for years my colleague Eric Kessler has been taking students on the Kansas Herpetological Society field trips (  Students walk fields WITH herpetologists, learning from them as they go!

I feel that we have the ultimate flipped classroom using this model!  We are out of the classroom 3-4 days a week.  We SEE/DO the concepts in real-world settings, the return to the classroom to apply and process what we have learned.  As we have these experiences, student vocabulary and knowledge increases at a rate faster than if we would have presented the material in the classroom.

Students keep a lab notebook where they document and diagram what they learn.  I have skills practicals where they are warranted.  Students practice writing gracious and meaningful thank you notes following our interactions.

I challenge you to add just ONE community interaction this semester!

Now a question for you:  how else would you hold students accountable for their learning?  Do you have other ideas for me from “in YOUR classroom” regarding accountablity in this setting?

Now Accepting Applications: 2015 Outstanding Biology Teacher of Kansas

Every ye2014 OBTA trophy 2ar, the Outstanding Biology Teacher Award (OBTA) program attempts to recognize an outstanding biology educator (grades 7-12 only) in each of the 50 states; Washington, DC; Canada; Puerto Rico; and overseas territories.

Candidates for this award do not have to be NABT members, but they must have at least three years of public, private, or parochial school teaching experience. A major portion of the nominee’s career must have been devoted to the teaching of biology/life science, and candidates are judged on their teaching ability and experience, cooperativeness in the school and community, inventiveness, initiative, and student-teacher relationships.

OBTA recipients are special guests of Carolina Biology Supply Company at the Honors Luncheon held at the NABT Professional Development Conference, receive gift certificates from Carolina Biological Supply Company, resources from other sponsors, and award certificates and complimentary one-year membership f2014 OBTA trophyrom NABT.

Our Kansas state chapter of NABT, supports this award each year. A committee of biology/life science teachers from across the state determine the 2015 OBTA.

You may self-nominate by completing the requirements found here:  OBTA requirements_2015
Nominate a colleague by forwarding him/her the attached information OR email the OBTA director, Kelley Tuel (, with his/her contact information. The director will send your nominee the application requirements.

CDC Science Ambassador Training – now accepting applications

2015 Come to Teacher Training at CDC!At the Fall KABT Conference, I spoke about my AMAZING experience at the CDC last July.

The application process has been opened up for the 2015 Science Ambassadors.  I encourage you to apply!  Please see the information below and/or distribute the atGroup Picture_CDC Signtached pdf among your collegues:

Centers for Disease Control and Prevention (CDC) invites middle- and high-school teachers to attend the 2015 CDC Science Ambassador Workshop. The free* 5-day professional development workshop focuses on training teachers to use examples from public health to illustrate basic math and science principals and concepts in the classroom. The Workskhop will be held from July 20-24 at CDC headquarters in Atlanta, Georgia.

Throughout the week, CDC scientists present information on current public health topics and collaborate with participants to develop challenging and innovative public health-based lesson plans that align with Next Generation Science Standards. As part of the 2015 Science Ambassador Workshop, participants will have the opportunity to:

  • Attend seminars on current public health topics presented by CDC scientists
  • Collaborate with CDC scientists to develop lessons plans based on public health science topics that will be published on CDC’s website
  • Tour CDC’s state-of-the-art headquarters, including the Emergency Operations Center and the David J. Sencer CDC Museum
  • Earn 4.0 Continuing Education Units (CEUs)
  • Expand professional networks

To be considered for participation, please e-mail the following materials to by April 15, 2015:

  • Curriculum vitae or résumé
  • Recommendation letter from your school’s principal, department chair, or a colleague.
  • Personal statement (500 words or less) explaining your interest in the workshop, your expectations of the workshop, and how the workshop aligns with your teaching goals

*There is no charge for this workshop but participants are responsible for their own transportation, lodging and meals.

If you have any questions about this workshop or any of our other materials or activities, please visit the website at: and/or to contact us by e-mail at Come to Teacher Training at CDC!