VCU news

By Brian McNeill

Derek Johnson, Ph.D., a biology professor at Virginia Commonwealth University, sat at the head of his class, role-playing as the head of the Centers for Diseases Control, probing the response to the Ebola case in Texas. Johnson's students played the role of CDC experts on infectious diseases.

"We have this case, Thomas Duncan. He arrived in Dallas on Sept. 20. All of you have my briefing here. And so we need to worry about secondary infection," Johnson said. "Which contacts should we trace, and which should we not be worried about?"

"Definitely the people who were living with him in the apartment when he started showing symptoms on Sept. 24," said Zeeshan Qureshi, a biology major.

"Since he started showing symptoms on the 24th and went to the hospital, we should make sure that the triage nurse, the standing doctor and whoever else he came in contact with at the hospital during his visit are all monitored," added biology and chemistry major Kevin Luu.

What about all of Duncan's international flights? Johnson wondered.

"The briefing showed that he didn't show symptoms until Sept. 24," Luu said. "Before that, I don't think you need to trace further back. There's no point in going back in his flight history."

The real worry, biology major Stephen Whitenack suggested, is the two days after Sept. 24 before Duncan was admitted to the hospital, as well as the two days later when he was admitted again. "That's where the key tracing needs to take place," he said.

The class, Outbreaks and Epidemics, is offering VCU seniors an opportunity to explore the ongoing Ebola outbreak in real time.

Johnson, an expert on forest insect outbreaks in the Department of Biology in the College of Humanities and Sciences, said the course was not originally going to center on Ebola, but changed focus as events unfolded.

"When this course was scheduled in the spring, I envisioned that it would focus more on insect outbreaks and deal with some epidemics," he said. "However, once the Ebola epidemic became as large as it is, I realized that it was a unique opportunity to have a class follow an epidemic as it occurred."

When this course was scheduled in the spring, I envisioned that it would focus more on insect outbreaks and deal with some epidemics. ... However, once the Ebola epidemic became as large as it is, I realized that it was a unique opportunity to have a class follow an epidemic as it occurred.

The students have read several scholarly articles on the current and past Ebola outbreaks, and have been following the response by health agencies via regularly posted updates by the CDC and World Health Organization.

"This is really a subject that presents its own topics every week," Johnson said.

Among the topics explored by the course so far have been the history of Ebola, the outbreak in Africa and the response to Ebola cases in the United States.

The students also have learned how health officials use population models to follow epidemics and make predictions.

"There's a certain model — the basic type is called an SIR model — where you categorize a population into one of three categories — those who are susceptible, those who are infectious and those who are recovered and resistant to the virus," Johnson said.

The course has not only focused on Ebola, however. It has also looked at other disease outbreaks, such as measles.

"Measles is a very seasonal occurrence, which is largely driven by the bringing of new susceptible school children into a population," Johnson said. "In recent years, as the rate of vaccination has decreased largely due to the unfounded scares of autism, we're now seeing a higher prevalence of measles."

Measles and small pox, he added, are good examples to illustrate how vaccines can protect the entire population, not just those who are vaccinated.

"We can view infectious diseases in the SIR model context, and show, given a certain rate of spread of a disease, which is defined as the average number of people or hosts infected by any one host, what proportion of a population you have to vaccinate to prevent an epidemic."

The course is a senior-level capstone course, which aims to bring together many aspects of the students' academic career at VCU.

As part of the course's requirements, each student will write a term paper. "I've given them the freedom to choose a topic related to Ebola, or another infectious disease, whether present or past," Johnson said.

In the spring semester, Johnson will teach a more traditional biology course titled Infectious Disease Ecology, which will explore the ecological drivers of infectious diseases in human, animal and plant populations.  

For Whitenack, the course offered an unusual and exciting opportunity to learn about Ebola and the ongoing response in real time.

"I found the topic interesting because it was relevant," he said. "Ebola was happening. So I was like, 'Let's do this.' Because it's real-life."

 

Feature image at top: Biology professor Derek Johnson leads his Outbreaks and Epidemics class in a roleplaying exercise to evaluate the response to Ebola in Texas.

 

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