Brucellosis is clinically known as contact brucellosis, which is caused by Brucella infections. For individuals who have been treated for a week and still have a low-grade fever, it is considered to be caused by inappropriate use of medication, insufficient course of treatment, and the combination of other complications. 1. Improper use of medication: the use of antibiotic drugs sensitive to Brucella is currently the main means of treatment to deal with contact brucellosis, and patients often need to be treated through a combination of drugs. Therefore, if patients abuse antibiotic drugs or change drugs on their own, it may lead to the pathogens in the body can not be killed, causing the disease to recur, so that their own recurring low fever. 2. Insufficient course of treatment: the treatment of contact brucellosis is not an overnight thing, the World Health Organization recommended rifampicin and doxycycline combination of six weeks as the first choice of treatment to deal with the disease, so the treatment of a week and still have a low fever to consider the use of medication insufficient course of treatment. 3. Combination of other complications: If the disease leads to complications such as meningitis and infective endocarditis, it may also cause low fever and other unusual symptoms even after treatment. Contact brucellosis requires the principles of early, combined, adequate dosage and duration of medication in order for the condition to be effectively treated. In addition, the disease may recur, so it is important for patients to have regular checkups even if the disease is cured.