story by Homma Rafi
Director of Communications, School of Public Health
Dr. Gerardo Chowell, a mathematical epidemiologist in the School of Public Health, is producing daily 10-day forecasts of the cumulative number of confirmed cases of the coronavirus in China. Wuhan, the epicenter of the outbreak, is the capital city in the province of Hubei.
Dr. Chowell’s initial forecast shows that the trajectory of the coronavirus outbreak in Hubei is following an exponential growth trend, while the outbreak in other provinces in China is growing following a sub-exponential growth profile. Learn more about what researchers at the School of Public Health are doing to monitor the outbreak.
1. What is a coronavirus and what are its origins?
This is a new virus that’s actually part of a large family of viruses known as coronaviruses. The new virus, known as 2019-nCoV, has been traced back to Wuhan, China, the capital of the Hubei province. A significant number of the early cases were in people who had visited a wet market in Wuhan, where animals for consumption are sold, suggesting that the virus jumped to humans from an animal source. Subsequently, many cases have resulted from person-to-person transmission, indicating that the virus is able to spread efficiently among humans.
To learn more about how the virus is spreading person-to-person, visit the CDC’s FAQ’s.
2. How is the coronavirus similar to the SARS virus and how do you predict it could spread in the United States?
This new coronavirus is about 90 percent genetically similar to SARS-CoV, which is also part of the coronavirus family and generated outbreaks in several parts of the world in 2003. However, 2019-nCoV appears to be less severe. So far, experts estimate the fatality rate at about 2 percent, compared to an average fatality rate of 10 percent for SARS. It is difficult to tell whether we will see a full-blown epidemic of 2019-nCoV in the United States or other developed countries. If past experience with SARS-CoV serves as any guide, the largest risk of transmission is inside hospitals or healthcare facilities. Putting in place enhanced precautions in these settings to deal with patients with respiratory symptoms, such as cough and shortness of breath, may go a long way to prevent nosocomial outbreaks or infections that have been caught in a hospital and are potentially caused by organisms that are resistant to antibiotics.
3. Your research uses mathematical models to help determine how to best address public health emergencies. Why are these tools so useful?
Mathematical models are useful tools to investigate the transmission potential of a pathogen by measuring how quickly the number of secondary cases is growing. Based on this information, it is possible to generate forecasts of the number of cases that are expected in the short and medium terms as well as assess the effect of various interventions. For instance, you could use these models to determine which segments of the population should be vaccinated when a vaccine becomes available.
4. How does the coronavirus outbreak directly relate to what epidemiology students can learn and are learning in the School of Public Health?
This is a great opportunity to put in practice the methodological toolkit that students are learning during the MPH program. At the Ph.D. level, students with a focus on infectious disease transmission and control have the skills to develop and calibrate models with different levels of complexity to generate forecasts of the epidemic in real time.
5. What are researchers doing at Georgia State to monitor the outbreak?
We are using mathematical and statistical models to predict the effects of various intervention strategies, such as vaccination and rapid detection and isolation of infectious individuals. We are also using those models to assess the effects of interventions and generate short-term forecasts of the trajectory of the epidemic. With my Ph.D. students and collaborators, we are making these daily forecasts publicly available at the following School of Public Health website: publichealth.gsu.edu/coronavirus
Dr. Gerardo Chowell
Professor, Department Chair
Department of Population Health Sciences
School of Public Health
Dr. Gerardo Chowell is professor of mathematical epidemiology in the concentration of Epidemiology & Biostatistics in the School of Public Health. He also holds an external affiliation as a Senior Research Fellow at the Division of International Epidemiology and Population Studies at the Fogarty International Center, National Institutes of Health.
Before joining Georgia State, Dr. Chowell was an associate professor in the School of Human Evolution and Social Change at Arizona State University.
Dr. Chowell is a member of the editorial boards of BMC Medicine, BMC Infectious Diseases, Epidemics, Mathematical Biosciences and Engineering, Infectious Disease Modeling, Scientific Reports, and PLOS One.