Chickens need to be exposed gradually to coccidia in the soil to be up an natural resistance. Many people place a small piece of sod in the brooder for the chicks to climb on and explore, and eat, getting some early exposure. Replace it every few days. There is no way to sterilize the ground or a coop. The best way to limit the amount of coccidia oocysts is to keep the bedding dry as possible. Stirring it daily, adding clean pine shavings to it, and removing soiled bedding is helpful.
Quaternary ammonia (not regular ammonia) is the kind that can kill coccidia. I would not recommend trying to disinfect your coop, but keep it clean and dry. They will develop resistance as they grow and are exposed to small amounts. Treat any outbreak of sickness. Some coccidia is resistant to amprollium or Corid, so use the other drugs (sulfa antibiotic or toltrazuril) if needed for a severe case.
Quaternary ammonia (not regular ammonia) is the kind that can kill coccidia. I would not recommend trying to disinfect your coop, but keep it clean and dry. They will develop resistance as they grow and are exposed to small amounts. Treat any outbreak of sickness. Some coccidia is resistant to amprollium or Corid, so use the other drugs (sulfa antibiotic or toltrazuril) if needed for a severe case.