Hello. Titres of typhoid bacteria vary from laboratory to laboratory. Kindly verify with your lab whether they consider it as positive. If the lab do consider it as positive, it is more likely that you are a chronic carrier rather than being repeatedly infected. Repeated infection is possible especially if food you consume is not prepared hygienically. Typhoid bacteria have a special affinity towards bile and can remain in a person s gall bladder for years together. Person may or may not have symptoms. There are different tests to determine whether you are a chronic carrier or not. These include blood tests, stool tests and even endoscopically obtained sample test. The treatment for chronic typhoid fever is different than that for acute typhoid fever. The course and dosage of antibiotics differ. Kindly consult your physician regarding the same. For boosting immunity, nothing better than a healthy diet and lifestyle. Hope this helps. Regards, Dr Geeta