As part of a joint taskforce report, researchers at Texas A&M University-Corpus Christi compared data on the COVID-19 pandemic in the Coastal Bend to data from Bexar County and elsewhere and showed the impact of easing or ending restrictions. The report was made during the researchers’ weekly presentation today to Corpus Christi City and Nueces County leaders.
In comparison to Bexar County, Harris County, and the rest of Texas, data from the Coastal Bend shows an earlier and somewhat smaller peak in COVID-19 cases. For reference, U.S. Census data shows populations of Bexar County at about 2 million, Harris County, about 4.7 million, and Nueces County, about 362,000.
"The Coastal Bend is doing well so far with the number of positive test cases continuing to decrease, including none during the past few days in Nueces County," said Dr. Philippe Tissot, Interim Director of the Conrad Blucher Institute (CBI) at Texas A&M-Corpus Christi. "While the total number of cases is still increasing in some surrounding areas such as Bexar County, the progression appears to be linear rather than exponential, which is a very good sign."
Dr. Chris Bird, Associate Professor of Biology, explained the project and discussed the major differences between three scenarios scientists looked at in their study: continue restrictions currently in place; ease some restrictions; or remove all restrictions.
"We predict that keeping the present Stay-at-Home measures keeps the number of infections low and under control for the foreseeable future, the next couple of months," Bird said. "Lifting all restrictions leads to a surge in the number of infections and the overwhelming of our hospital infrastructure.
The middle scenario shows what happens when Stay-at-Home is ended on April 30. The overall goal is to show the effect that rolling back interventions can have on COVID-19 and inspire us to find alternative ways of reducing the rate of transmissions, such as wearing face masks in public."
Another factor being considered by the team is the "seasonality" of the virus, defined as the potential change in the spread of the epidemic due to seasonal changes in temperature and humidity.
"Last week we decreased the transmission rate by 20% in the summer based upon a study by Harvard University that determined a 20% seasonal effect was a moderate estimate given what is known about other coronaviruses and flu," Bird said.
The team also is measuring the effectiveness of social distancing by looking at cell phone data. Because social distancing is such a critical part of preventing the virus from spreading from one person to another, A&M-Corpus Christi scientists are experimenting with a new tool to quantify social distancing in Corpus Christi and provide better information to decision makers.
"The data is based on daily information gathered from a portion of cell phone users and estimates how often people meet other people who are not part of their household," Tissot said. "More specifically, it counts when two devices are within 50 meters for less than 60 minutes."
The data, which cannot be traced back to individual users, shows how the daily number of human-human contacts outside of the home decreased dramatically between normal levels in February through the present Stay-at-Home order, estimated as about an 80% decrease due to the mitigation measures.
The team’s presentations and findings can be seen on a special dashboard: https://www.conradblucherinstitute.org/covid19.
In addition to Tissot and Bird, the A&M-Corpus Christi team includes Dr. Lucy Huang, Associate Professor of Geographic Information Science and coordinator of the Geospatial Systems Engineering Program in the Department of Computer Sciences; and Marine Biology Ph.D. candidate Jason Selwyn as lead modelers for the taskforce. Many others are gathering and verifying information, building the information pipeline, and developing the dashboards that provide the information to the public.
Faculty and researchers from CBI, the Life Sciences and Computer Sciences departments and the College of Nursing and Health Sciences form the core of the team as it collaborates with staff at the city, county, and local hospitals.