Hello, I understand your concern. I am Dr Arun Tank, Infectious diseases specialists, responding to you. - Widal test is the descision making test. If it is negative means the bacteria disappeared from the blood. If it is positive means they are present in the blood. - So if the widal is again positive, means you are having recurrence of infection. There is probability of resistant in the organism which causes recurrence. - you can do antimicrobial susceptibility testing and can give you antibiotic accordingly. I will be glad to answer your further query. Thank you for your contact to health care magic. Wish you a best health. Thank you, Dr Arun Tank.