Sexually Transmitted Infection Statistics


Data for three types of sexually transmitted infections (STIs), divided into four groups, are shown on this website: chlamydia, gonorrhea, primary and secondary syphilis (P&S syphilis) and all syphilis. Information for these infections is presently available for the years around 1999 through 2019. These tabulations are divided into basic trend tables and more detailed tables for a single period by gender and age; and by county or health district.

To view detailed information on STI statistics in your community,  start by selecting any of the tables to the left. The community-level tables provide STI data by Michigan's local health departments and counties; links to the community-level tables appear above.

Most of the statistical tables can be altered slightly to yield more information:

Confidence Interval: If this boxed is checked, tables that display rates will also display confidence intervals. Adding and subtracting the number shown after the ± symbol from the rate creates an interval indicating that the true rate lies between the lower and upper bounds with 95% statistical confidence.

Default year: Most of the statistical tables on this site have a year slider, so that a table can be displayed by year. Each time a new table is selected, the new table automatically updates to the default year. Changing the default year allows the user to move through tables for a preferred period, without adjusting the slider.

Map: This option applies only to ranked tables. If a ranked table is selected, it toggles the view between statistics and a map view.

Rates instead of cases: This option applies only to trend tables. If a trend table is selected, checking the box toggles the view between either counts or rates of cases.

Averaging: The "sex by age" tables provide a convenient grouping of common STI statistics. The averaging list box changes the underlying statistic of the table (where applicable) from cases to total cases, average cases or average rates. Averaging provides more stable estimates over time, especially in smaller age groups or communities with smaller populations.