Epidemiological features of brucellosis and factors affecting its treatment failure and relapse in Qom Province, Iran

Background: Brucellosis is one of the major health problems in many areas of the world, especially in the Mediterranean and the Middle East regions.

Objective: To determine the epidemiological characteristics, clinical signs, and risk factors of relapse rate in patients with brucellosis, Qom Province, Iran.

Methods: A descriptive-analytic study was conducted on 410 confirmed brucellosis cases in Qom Province, central Iran, from 2015 to 2019, based on epidemiological checklists and according to the Iran Ministry of Health and Medical Education (MOHME). Univariate and multiple logistic regression analyses were conducted using Stata software version 14.

Results: The relapse rate of brucellosis was 6.6% until nine months after starting the treatment, and all recurrent cases were infected by Brucella melitensis. Based on univariate logistic regression analysis, the delayed treatment and type species of Brucella were significant factors affecting the relapse of brucellosis. The relapse rates were 5.4%, 6.2%, and 20.0% in patients whose delayed treatments were <50, 51-150, and >151days, respectively. Based on the multiple logistic regression, it was observed that delayed treatment >50 days increased the rate of relapse more than four times.

Conclusion: The delayed initiation of treatment was a significant factor influencing the relapse of brucellosis; therefore, it is necessary to provide enough diagnostic and laboratory facilities, and people need to be educated about the signs and symptoms of the disease.

Funding: Funding for this research was provided by the Research and Technology Center of Qom University of Medical Sciences, Qom, Iran.