Incidence and warning signs for complications of human brucellosis: a multi-center observational study from China.

BACKGROUND: Brucellosis is a severe zoonotic disease that is often overlooked, particularly in impoverished countries. Timely identification of focal complications in brucellosis is crucial for improving treatment outcomes. However, there is currently a lack of established indicators or biomarkers for diagnosing these complications. Therefore, this study aimed to investigate potential warning signs of focal complications in human brucellosis, with the goal of providing practical parameters for clinicians to aid in the diagnosis and management of patients. METHODS: A multi-center cross-sectional study was conducted in China from December 2019 to August 2021. The study aimed to investigate the clinical characteristics and complications of patients with brucellosis using a questionnaire survey and medical record system. The presence of warning signs for complications was assessed using univariate and multivariate logistic regression models. Receiver operating characteristic (ROC) curves and the area under the curve (AUC) were used for variable screening and model evaluation. RESULTS: A total of 880 participants diagnosed with human brucellosis were enrolled. The median age of the patients was 50 years [interquartile range (IQR): 41.5-58.0], and 54.8% had complications. The most common organ system affected by complications was the osteoarticular system (43.1%), with peripheral arthritis (30.0%), spondylitis (16.6%), paravertebral abscess (5.0%), and sacroiliitis (2.7%) being the most prevalent. Complications in other organ systems included the genitourinary system (4.7%), respiratory system (4.7%), and hematologic system (4.6%). Several factors were found to be associated with focal brucellosis. These factors included a long delay in diagnosis [odds ratio (OR) = 3.963, 95% confidence interval (CI) 1.906-8.238 for > 90 days], the presence of underlying disease (OR = 1.675, 95% CI 1.176-2.384), arthralgia (OR = 3.197, 95% CI 1.986-5.148), eye bulging pain (OR = 3.482, 95% CI 1.349-8.988), C-reactive protein (CRP) > 10 mg/L (OR = 1.910, 95% CI 1.310-2.784) and erythrocyte sedimentation rate (ESR) elevation (OR = 1.663, 95% CI 1.145-2.415). The optimal cutoff value in ROC analysis was > 5.4 mg/L for CRP (sensitivity 73.4% and specificity 51.9%) and > 25 mm/h for ESR (sensitivity 47.9% and specificity 71.1%). CONCLUSIONS: More than 50% of patients with brucellosis experienced complications. Factors such as diagnostic delay, underlying disease, arthralgia, eye pain, and elevated levels of CRP and ESR were identified as significant markers for the development of complications. Therefore, patients presenting with these conditions should be closely monitored for potential complications, regardless of their culture results and standard tube agglutination test titers.

Investigation on the knowledge and protective behavior of brucellosis prevention and control among high-risk populations in Huocheng County, Xinjiang Uygur Autonomous Region from 2019 to 2020 / 中华地方病学杂志

Objective:To investigate the knowledge and compliance status of prevention and control of brucellosis among high-risk populations in counties and districts with high incidence of brucellosis in Xinjiang Uygur Autonomous Region (Xinjiang for brief), and to provide scientific basis for prevention and control of brucellosis and health education for high-risk populations.Methods:Huocheng County, a high incidence county of brucellosis in Xinjiang, was selected as the survey site. Three to six townships were selected, and two to three administrative villages were selected from each township as the survey villages. People over 18 years old and engaged in livestock breeding such as cattle and sheep breeders, livestock product processors, veterinarians and medical personnel were selected as the survey subjects. Face-to-face surveys were conducted by professional trained investigators in autumn and winter (December 2019 to January 2020) and spring and summer (April to July 2020). The survey included general demographic information, awareness of brucellosis prevention and control knowledge and the use of protective equipment.Results:A total of 600 people were surveyed, and 597 people completed the questionnaire, with an effective response rate of 99.50% (597/600). The overall awareness rate of brucellosis prevention and control knowledge was 68.23% (10 184/14 925), among which the awareness rate of clinical symptoms of human infection with brucellosis was high, at 73.53% (3 073/4 179). There were statistically significant differences in the awareness rate of main source of infection, main transmission route and clinical symptoms of human infection with brucellosis among people of different gender, age, nationality, education level and occupation ( P < 0.05). Among them, the awareness rate of clinical symptoms of human infection with brucellosis among veterinarians and medical personnel was 85.38% (514/602). The utilization rate of protective equipment such as rubber shoes and work clothes was high, which was 63.48% (379/597) and 60.97% (364/597), respectively. There were statistically significant differences in the utilization rate of protective equipment among different nationality, education level and occupation ( P < 0.05). Among them, The utilization rate of work clothes was the highest among people with college education or above, veterinarians and medical personnel, which was 82.61% (57/69) and 93.02% (80/86), respectively. Conclusions:The overall awareness rate of brucellosis prevention and control knowledge in high-risk groups in Huocheng County of Xinjiang is low, especially among high-risk groups such as those who are illiterate or have little literacy, and farmers, the awareness rate is low and the awareness of prevention and control is weak. There is a risk of brucellosis infection. It is necessary to further strengthen the education of brucellosis prevention and control knowledge among these groups.