Spatiotemporal distribution of syphilis cases in Wenzhou, 2016–2019

  Objective  To analyze the spatiotemporal distribution of syphilis cases in Wenzhou from 2016 to 2019 and provide evidence for prevention and control of syphilis.

  Methods  Using software ArcGIS 10.2 as a platform for data management and presentation, a syphilis spatial distribution database in Wenzhou from 2016 to 2019 was established, and spatial autocorrelation analysis was performed based on the incidence of syphilis in Wenzhou during this period. Software SaTScan 9.6 was used for spatiotemporal scanning analysis.

  Results  From 2016 to 2019, a total of 13 778 syphilis cases were reported in Wenzhou, in which 13 550 were included in this analysis. The average annual incidence rate was 37.13/100 000 (range: 0–365.14/100 000). The results of global spatial autocorrelation analysis indicated that the distribution of syphilis cases showed clustering. The result of local Moran’s I autocorrelation analysis found 4 high-high clustering areas, covering 18 townships, in southern Wenzhou. Result from the Getis-Ord General G spatial autocorrelation analysis showed 31 “positive hot spots” and 5 “negative hot spots”. Using software SaTScan 9.6, results from the Phased spatial-temporal analysis identified 7 clustering areas.

  Conclusion  From 2016 to 2019, the incidence of syphilis in Wenzhou was not randomly distributed but showed temporal-spatial clustering. It is necessary to take targeted syphilis prevention and control measures in areas at high risk.