There is little doubt that COVID-19 has already radically transformed life in San Antonio. The impacts of the virus have reverberated throughout our community, whether it’s the postponement of Fiesta until the fall, the AT&T Center sitting dormant, or the customers forming long lines at H-E-B each morning hoping to obtain the hottest commodity in town, toilet paper.

However, data recently released by the City of San Antonio indicates that confirmed COVID-19 cases are not distributed equally throughout the city. Certain communities are potentially being impacted more severely by the virus, with more cases on San Antonio’s North Side than on the South Side – a Charles Dickensian “tale of two cities.”

The City began publishing the number of confirmed COVID-19 cases at the zip code level on March 28. With one week’s worth of data now available, it is useful to analyze maps in hopes of understanding where cases are most abundant, how the cases have spread spatially, and potentially why.

Clearly, the March 28 debut of the granular zip code COVID-19 data was long after the first confirmed case in San Antonio. By that time, over 40 zip codes already had at least one confirmed case of COVID-19. There was also an initial hotspot of nine to 12 cases in the 78209 zip code, which corresponds roughly with Alamo Heights and Terrell Hills.

There are several mechanisms that may have potentially contributed to this initial hotspot. It is one of the more affluent communities in the city, which has several implications. First, it suggests that the population has the means to travel both nationally and internationally for business and/or leisure, which would increase the likelihood of being exposed. Second, more affluent communities likely have better access to testing for the virus. Finally, the area is home to the largest number of health care practitioners within Loop 410.

Portions of this community therefore faced higher likelihoods of being exposed due to their occupation. They also potentially benefited from the earliest phases of testing in the city being limited largely to health care workers and others on the frontlines fighting the virus.

The spatial progression of COVID-19 cases over the subsequent seven days seemed to further support a “tale of two cities” narrative. Confirmed cases of COVID-19 generally continued to cluster in the more affluent northern half of San Antonio, where more health care practitioners also reside.

Conversely, a relatively limited number of confirmed COVID-19 cases were reported over the past week on San Antonio’s South Side. The optimist might conclude this is due to a genuine lack of COVID-19 cases in the area. However, it is impossible to overlook the possibility that inequities in access to testing have resulted in underreporting within less-affluent portions of the city.

There were also other notable patterns in COVID-19 cases revealed over the past week. On March 30, there were surprisingly few alterations in the number of cases reported at the zip code level. The overall lack of new cases was due to a testing backlog. Mayor Ron Nirenberg stated that, “nearly 1,000 test results are backlogged at the state lab from our drive-through facility at Freeman Coliseum.”

Furthermore, in recent days, the 78222 zip code on the Southeast Side has become the new leading hotspot in the city with 70-plus cases. That was attributable to the well-documented outbreak at the Southeast Nursing and Rehabilitation Center, further demonstrating the vulnerability of health care facilities to COVID-19.

The animated map below shows confirmed coronavirus cases geographically over time:

Moving forward, it will be interesting to monitor how the continued relaxation of the criteria to get tested might transform the geography of COVID-19 cases in San Antonio, particularly as it relates to the potential underreporting on the South Side.

Despite the current “tale of two cities” narrative regarding confirmed COVID-19 cases in San Antonio, the data indicates that no region of the city is completely safe from the virus. Roughly two thirds of all zip codes had at least one confirmed case as of April 3.

Additionally, as the recent outbreak at the Southeast Nursing and Rehabilitation Center illustrates, new spatial hotspots can develop quickly. These factors collectively highlight the importance of diligently following Nirenberg’s Stay Home, Work Safe orders so we can hopefully protect one another, slow the spread of COVID-19, and return to our normal lives faster.

Dr. Debbage is an assistant professor of geography and environmental sustainability in the Department of Political Science and Geography at the University of Texas at San Antonio. His research focuses...