Professor details how models are used in estimating the number of COVID-19 deaths

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Bob Norton, chair of the Auburn University Food System Institute’s Food and Water Defense Working Group, discusses how modeling is conducted when estimates are made on the possible number of COVID-19 deaths. He also provides information on why certain states are seeing higher numbers, and tells why the food supply is safe.

How does modeling work in the estimate of 100,000-240,000 deaths from COVID 19?

The estimates mentioned over the last two weeks by President Trump and his COVID-19 Taskforce are the result of models, which have been developed inside and outside of government. The numbers referenced were given at the March 31 Taskforce press briefing.

Models used in making the estimates of 100,000-240,000 are based upon data that is coming from Italy and other parts of Europe, China and cities in the United States, which are being significantly affected by COVID-19. A little background: “Models” are complex computer programs that include a variety of also complex mathematical formulas and statistical analyses that estimate what might happen, given some set of circumstances (if A, then B, C, D could happen). Models are very dynamic, in that the results of the mathematical formulas and analyses are altered over time as new data is added from trends and actual case numbers, or other observations. I offer this very simplified explanation to stress that models are dynamic and the results may be altered, sometimes subtly, sometime more significantly, as new data is input.

To avoid dependence on any one model developed by a set of scientists, statisticians and modelers, the decision makers often look across a series of models and then consider the trends. Looking across the models, we can’t say that they are “accurate” in that only time will tell how close to the real figures. We can, however, say they are plausible, hence the warning by the president and the taskforce that the next two weeks are likely to be very painful. Individuals with one or more underlying medical conditions can become deeply in trouble if they are infected with the COVID-19 virus. That is why it is critical that they take this warning very seriously, as well as those around them.

Does that estimate mostly affect certain states?

There is no question that states like New York, California and Louisiana are most heavily infected right now. Those state trends are likely to continue for possibly several months. There are many reasons for this trend, most prominent of which is those state’s population densities and special features (e.g., Mardi Gras), which is now associated with a rapidly growing number of new cases. That being said, no state is a safe sanctuary from the disease. Even Alabama is seeing a spike in the number of cases, which is unfortunately is happening at the same time when parts of Alabama are experiencing difficulties in acquiring the COVID-19 test. Medical professionals in these areas are using presumptive diagnosis (signs and symptoms) to identify potentially infected patients. Unfortunately, increasing medical evidence indicates a percentage of infected individuals are actively shedding the virus even though they may have only very mild or no symptoms at all. That means everyone you meet outside the circle of your family could potentially infect you. Social distancing, insulating yourself by staying at home whenever possible and assiduous handwashing are essential activities needed to avoid infection. For the time being, don’t go out into public places if you don’t have to.

Will the food supply remain stable?

The food supply is stable and safe. Food corporations have already adjusted the way they conduct business to assure there are no interruptions in the food supply. I interact regularly with several very large food corporations and I am very impressed on how seriously they take COVID-19 and how they are adjusting business decisions according to new data they receive from the federal government and private analysis groups. Food safety is at the forefront of everything they do.

Logistics comes in a close second. Their focus now is to continue to produce the safest food supply in the world, delivering it to the consumer without interruption. Don’t worry if you go into a store and see some empty shelves. This is a reflection of local buying and often hording. It is not reflective of an interruption or disruption in the food supply. If something you want to eat isn’t on the shelf or in the freezer of the local grocery store, find an acceptable alternative. The food supply is safe and being closely monitored by a lot of people, whose job it is to stay vigilant and look for threats. That is in fact one of my responsibilities—food defense.     

About Bob Norton:

Bob Norton has 35 years of experience in veterinary infectious diseases, national security, bioterrorism and agroterrorism detection and defense. A veterinary microbiologist by training, he serves as the chair of the Auburn University Food System Institute’s Food and Water Defense Working Group and is a professor of veterinary infectious diseases, biosecurity and public health in the Auburn University College of Agriculture’s Department of Poultry Science. He is also the national security programs coordinator for The Futures Laboratory, an outreach effort to the Department of Defense. He is a long-time consultant to the U.S. military and federal and state law enforcement agencies and is editor of Bob Norton’s Food Defense Blog.

Auburn University is a nationally ranked land grant institution recognized for its commitment to world-class scholarship, interdisciplinary research with an elite, top-tier Carnegie R1 classification, life-changing outreach with Carnegie’s Community Engagement designation and an undergraduate education experience second to none. Auburn is home to more than 30,000 students, and its faculty and research partners collaborate to develop and deliver meaningful scholarship, science and technology-based advancements that meet pressing regional, national and global needs. Auburn’s commitment to active student engagement, professional success and public/private partnership drives a growing reputation for outreach and extension that delivers broad economic, health and societal impact.