Which of the following is true about typhoid?

Convalescent carriers excrete the bacilli for 6-8 weeks.Persons who excrete the bacilli for more than a year after a clinical attack are called chronic carriers.In chronic carriers, the organism persists in the gallbladder. Vi antibodies are present in about 80% 0f chronic carriersFecal carriers are more frequent than urinary carriers. The chronic urinary carrier state is often associated with some abnormality of the urinary tract.Ampicillin or amoxicillin + Probenecid for 6 weeks achieve eradication in 70% of chronic carriersPark 23e pg: 236