Greetings, welcome to the Forums.
In areas where Hookworms (Necator americanus) are endemic, it is almost impossible to completely eliminate them from the soil. However, if you do not keep dogs or outdoor cats, their numbers will be reduced. Mulching all bare soil with wood chip bark mulch (and layers of cardboard) will also help reduce the parasite load and your exposure to it. Still, as a previous poster mentioned, wild and feral animals will still introduce these parasites to your garden to some degree.
Chemical treatments will be expensive, toxic, and only effective if repeatedly applied in large amounts as the soil would need to be drenched. This soil drenching will also be toxic to a wide range of beneficial invertebrates. Home remedies such as borax or salt water will also be toxic to plants.
The best strategy in this situation is to maintain excellent sanitation. Do not keep outdoor pets. Always wear shoes in your garden, and gloves when planting or moving soil. A garden composed of trees, shrubs, and long-lived perennial will require less soil interaction. Containers and raised beds will also reduce exposure risk, though with time, contamination of this soil may also occur. Of course, you can still plant annuals and have a vegetable garden, just plant wearing gloves. Growing root crops would likely require additional care and caution.
Heat Solarization may be an effective option for sterilizing bare soil before planting. However, solarization works best in hot weather (Summer) and requires covering the soil with clear plastic for at least a month. Therefore this would be a major disruption to any Summer vegetable garden.
