Under Missouri Revised Statute Chapter 192 Department of Health and Senior Services Section 192.300 the county health center board may make and promulgate orders, ordinances, rules or regulations, respectively as will tend to enhance the public health and prevent the entrance of infectious, contagious, communicable or dangerous diseases into such county.  After the promulgation and adoption of such orders, ordinances, rules or regulations by county health board, county health board shall make and enter an order or record declaring such orders, ordinances, rules or regulations to be printed and available for distribution to the public in the office of the county clerk, and shall require a copy of such order to be published in some newspaper in the county in three successive weeks, not later than thirty days after the entry of such order, ordinance, rule or regulation. Any person, firm, corporation or association which violates any of the orders or ordinances adopted, promulgated and published by such county commission is guilty of a misdemeanor and shall be prosecuted, tried and fined as otherwise provided by law.

This would allow for Quarantine and Isolation orders to be issued but the Dallas County Health Department has no way to police the actions of Dallas County residents.  Educating the public on the need for social distance strategies will be important.