As of December 10, 2020, the Springfield Greene County Health Department provides an extensive dashboard with COVID surveillance information. The charts give a quick overview of various measures and can be adjusted to show specific data better. You can often switch the view to "Table" and see the underlying data. That data is not downloadable but some of it is available via state and national data sources.
Local testing labs and care institutions are required to report surveillance data to either the Missouri DHSS and/or the Greene County Health Department. The DHSS and county health then transfer information and reconcile data as needed.
The Springfield Greene County Health Department has an extensive number of web pages explaining the cities response to the COVID pandemic. Springfield city code for COVID-19 was in article 8 via the Municode searchable and browsable interface. Those codes no longer apply. In addition, you can also find the signed and scanned bills and ordinances by searching for "COVID".
Note that Greene County does not have any surveillance specific laws. Rather, that is covered at the state level. See links on that page for specific laws.