SARS-CoV-2 Positivity Rates Among Children of Racial and Ethnic Minority Groups in Mississippi

We performed a retrospective study using a deidentified COVID-19 registry at the University of Mississippi Medical Center, which was deemed nonhuman subjects research per the institutional review board. The University performs SARS-CoV-2 reverse transcriptase polymerase chain reaction (RT-PCR) on nasopharyngeal samples collected at university hospitals and ambulatory and drive-by clinics, health departments, and 12 hospitals and clinics outside of the university network statewide, representing a unique and diverse data set from private and public health services. Children aged ≤18 years who underwent SARS-CoV-2 RT-PCR between March 11, 2020, and August 12, 2020, were included in the analysis. Testing for any indication was included, as per previous reports.⁸ 

The primary exposure of interest was self-reported race and ethnicity. American Indian, Alaska Native, Asian American, Native Hawaiian or Pacific Islander, and multiracial were categorized as “other” races, on the basis of US Census standards (https://www.census.gov). Health insurance status was used as a surrogate for socioeconomic status and was categorized as Medicaid, private, and others. The primary outcome of interest was positive SARS-CoV-2 RT-PCR. Positivity rates were calculated as the number of positive cases divided by total individuals tested.

Bivariate analysis was performed by using a Pearson χ² test. Multivariable analysis was performed by developing a logistic regression model, and R software version 3.5.2 was used. Two-sided significance level was set at 0.05.

Of 4802 children undergoing SARS-CoV-2 RT-PCR, 623 had a positive test result (13.0%). Minority children had higher positivity rates (non-Hispanic Black: 15.8%, Hispanic: 24.6%) than non-Hispanic white children (5.9%) (Table 1). In multivariable analysis, the risk of nonwhite race and ethnicity remained substantial (Table 1). Of note, the “other insurance” category included Medicaid (2 patients), self-pay (1984 patients), and other insurance (65 patients).

Testing capacity expanded over the study period (Fig 1). Rates in Hispanic and other race children were erratic. Positivity rates in Black and white children increased over time. The rate in Black children was consistently and considerably higher than that of white children (Fig 1). Notably, positivity rates in the last 7 to 8 weeks of the study period (July through August 2020) were ∼20% among non-Hispanic Black children. These data are reflected in the statewide data reported to the American Academy of Pediatrics, which has shown that Mississippi is among the top in cumulative cases per 100 000 as of the most recent report.⁹ 

We found substantially higher positivity rates for SARS-CoV-2 testing in minority children compared with white counterparts in Mississippi. This is the first report of positivity rate in children in the American Deep South, where health disparities are historic, and in Mississippi, one of the most resource-limited American states. In addition, in this study, we review a larger sample size and wider state-coverage area than similar previous reports in children, and we cover the period from the beginning of epidemic to the lockdown and the release of lockdown measures with the start of the school year.

Potential limitations of our study include those inherent in its retrospective design. Residual confounding in the regression model, which included health insurance status as a surrogate for socioeconomic status, is possible, although the high magnitude of difference after adjusting for available covariates suggests the presence of disparities. Also, as a single-center study, selection bias cannot be excluded in inferring the population level estimates, although wide coverage of testing in the state would theoretically mitigate this weakness.

These results highlight the need for more aggressive public health interventions targeted to children,¹⁰  and minority children should not be left behind.

We thank Krishna Ayyalasomayajula, University of Mississippi Medical Center Biobank, and Ashish Jannela, Center for Informatics and Analytics at the University of Mississippi Medical Center for creating the COVID-19 research registry. No compensation was provided to individuals listed here for their role.

COVID-19

coronavirus disease 2019

RT-PCR

reverse transcriptase polymerase chain reaction

SARS-CoV-2

severe acute respiratory syndrome coronavirus 2