2218. Spatial Epidemiology of Gonorrhea Incidence Among Women in Chicago
Authors: Flores John , Kolak Marynia , Schneider John 
Published: December 2022

Background

Neisseria gonorrhea is the second most prevalent sexually transmitted infection (STI) in the US with increasing incidence. Untreated, it leads to devastating sequelae for nonpregnant women, pregnant women, and their neonates. Geographic clustering of gonorrhea coincides with clustering of other risk factors and may help guide interventions. We utilize Geographic Information Systems (GIS) software to map gonorrhea incidence among women in Chicago, and examine factors associated with the spatial distribution of infection.

Methods

Chicago Department of Public Health data sets and shape files were available through the Chicago Data Portal. ArcGIS was utilized for map illustrating and data analysis. Ordinary Least Squares (OLS) Regression was utilized using the dependent variable of Gonorrhea incidence in women per Chicago Community Area (CCA), with various explanatory variables. Within the OLS, the Koenker Statistic (KS) was reported and from this a Geographically Weighted Regression (GWR) tool was run for combinations with statistically significant KS.

Results

The highest incidence is shown in the southern and western CCA’s, with hospitals clustered in the northern and southeastern CCA’s & clinics with gaps primarily noted in the southern and northwestern CCA’s. (Figure 1.) Teen pregnancy incidence (TP), infant mortality (IM), and first trimester prenatal care, had statistical significance of the robust probability for all of their explanatory variables, and VIF’s less than 2 for all explanatory variables, JBS were not statistically significant, and AICc were approximately 1170 demonstrating stable OLS. (Figure 2&3) TP & IM did have a statistically significant KS and GWR was run demonstrating random spatial pattern. This confirms TP & IM as predictors for gonorrheal incidence had variable predictability throughout the CCA’s and GWR improves the model outcome. Both combinations spatially explain gonorrhea incidence.

Map of Gonorrhea Incidence among Females in 2006-2010 Figure 1:The data of the incidence of gonorrhea in females was mapped with 5 separate classifications created and displayed in the form of a map. Also included on the map were hospitals in the city, and Chicago Department of Public Health clinic locations where free STI management could take place. illustrates gonorrhea incidence rates (per 100,000) within the 77 Chicago Community Areas (CCA) of the city. The darker shades of green correspond with higher incidence. The highest incidence is shown to be greatest in the southern and western CCA’s. Also illustrated are the locations of the hospitals within the city in addition to CDPH clinics that are Federally Qualified Health Clinics (FQHC) that offer services for treatment at a reduced or free cost depending on health insurance status. The majority of the hospitals are shown to clustered in the northern and southeastern CCA’s. The clinics are more evenly spaced out with gaps primarily noted in the southern and northwestern CCA’s.

The Ordinary Least Squares (OLS) regression results are illustrated in Table 1 above. The results are shown for six separate regressions: chlamydia incidence, Natality (teen pregnancy incidence [TP], percent of live births that were preterm [Preterm], fetal low birth percentage [LBW], prenatal care in the 1st trimester rate [PNC 1T], infant mortality rate [IM]), poverty (total # below poverty line per 100,000), poverty & chlamydia, TP & IM, TP & IM & PNC 1T, and all coefficients (natality incidence, poverty incidence, chlamydia incidence, fertility rate).

Utilizing ArcGIS software, OLS Regression was mapped with the 77 Chicago Community Areas (CCA) with Gonorrhea Infection Incidence per CCA as the dependent variable and Teen Pregnancy (TP), Infant Mortality (IM) and 1st trimester prenatal care (1TM) incidence per CCA as the explanatory variables. Regression reported with standard deviation (SD) and color coded based off quantity of SD. Map shapefile is of the 77 CCA’s. Overlying are Hospitals and Chicago Department of Public Health (CDPH) clinic locations as made available through CDPH public domain website.

Conclusion

Teen pregnancy rates, infant mortality rates, and prenatal care in the first trimester explain some of the spatial patterns of gonorrhea incidence of females in Chicago. Identification of these factors identified should prompt providers to ensure enhanced testing of gonorrhea and other STI’s to reduce burden in areas of high incidence.

Disclosures

All Authors: No reported disclosures.