In the commercial production of beef (or any meat) jerky, how is the threat of parasites handled?
The at-home recipes are simply soaking the meat in a salt solution, then drying. Is this sufficient to kill parasites?
In the US, commercial jerky is inspected by the Food Safety and Inspection Service help ensure safety. See the FSIS Compliance Guideline for Meat and Poultry Jerky Produced by Small and Very Small Establishments for detailed information on commercial jerky preparation methods, which must include a "lethality" step based on heat, acidity, or other means to ensure pathogens are killed. They may also use more sophisticated methods to ensure proper drying.
Googling "jerky safety" will yield a wealth of University Extension results based on FDA research, providing specific recipes for safely creating jerky at home.
Traditional methods (soaking in brine, then drying) are not sufficient to kill all pathogens (not just parasites). The FDA now recommends the the "hot pickle cure" method as the most effective way of creating safe jerky.
See for example the recipe published via Cornell. In summary: