Coronavirus is what disease-ecologists call a newly emerging disease. A newly emerging disease is one that has newly appeared in a population or has existed previously but is increasing in incidence and geographic range. CoVID-19 is also a zoonotic disease which means it was transferred from wildlife to humans. The incidence of newly emerging zoonotic diseases such as CoVID-19 has been increasing and the coronavirus pandemic is an example of this trend.
While we do know the above information about coronavirus, a lot is still unknown which is why the stakes are so high. Some questions scientists and physicians are still asking are:
- What is the reservoir host that coronavirus came from (A reservoir host is an animal population that transmits a disease to humans either directly or through a vector)?
- What are the long term health effects of coronavirus?
- Can people contract it more than once?
- How long do antibodies last?
- Why are some people asymptomatic and others not?
These questions are important, but one of the hardest to answer is: How do we safely return to some semblance of a normal life? What should we do about college campuses reopening? There are a lot of opinions about this topic and it has become very polarized. However, the politicization of a scientific issue is not helpful.
That is why it’s exciting that Professor Ken Field at Bucknell has created an SEIR model to mathematically predict whether it is feasible to be on campus, and how long the campus might stay open. Dr. Field is a Biology 205 professor, as well as an upper-level Biology professor for Immunology and Advanced Data Analysis. His research focuses on immunology and cell biology and he is also a Biology Department Chair. For this specific project, he made an SEIR model which stands for Susceptible, Exposed, Infective, and Removed. The model, which he continuously updates, accounts for every student (who is studying in person) and mathematically predicts which of these four groups they will be in at different points in time. A susceptible person is not infected but is at risk of infection, an infective is someone who can give the pathogen to someone else, and a removed person is someone who has either contracted the virus and got better or died. The model assumes that every member of the population has different levels of contact with each other and that some cases will come from outside of campus.
Click here to see Professor Field's explanation of the model. I happen to be featured in one of the videos asking more questions about how the model works and how to strengthen our mitigation techniques. Bucknell Medical Director Dr. Catherine O’Neil is also featured in one of them, answering questions and giving a physician’s perspective. Professor Field also updates his youtube channel often with more videos discussing COVID related issues and recent updates to his model based on new data.
What is clear from these videos is that mitigation strategies significantly lower the number of students that are exposed or infective. Social distancing, mask-wearing, hand-washing, good ventilation, and cleaning have a significant impact on the ability of students to stay. However, in a prospective scenario in which mitigation strategies are not followed, numbers of exposed and infective students are high and the campus is in a situation where it has to close. It is mathematically and biologically clear that students need to follow mitigation strategies to keep themselves and others safe. It also must be highlighted that Bucknell’s policy of two negative tests before you arrive on campus and then subsequent testing every 10 days is very important to identifying those infective people and preventing them from exposing others.
Give doctors time to save their patients and open up hospital beds, give scientists enough time to make a safe vaccine, and learn more about the virus, and please strive to provide a safe environment for faculty and staff to come to work so they can provide for their families. Doing all these things will help keep the campus open as long as possible and now it has been mathematically proven it will work for our community.
Acknowledgments: I would like to thank Professor Ken Field for making this model and inviting me to be in one of his videos to discuss them. I would also like to thank both Professor Ken Field and Professor DeeAnn Reeder for teaching me everything I know about disease ecology and immunology and helping me expand my knowledge through research.
Sources: De Jong, C., Field, H., Newman, S. H., & Epstien, J. (2011). Emerging Infectious Diseases. Retrieved September 04, 2020, http://www.fao.org/3/a-i2407e.pdf