Epidemiology and awareness of brucellosis in populations at high risk in Hulunbuir, Inner Mongolia Autonomous Region, 2010–2019

  Objective  To analyze the surveillance results of brucellosis in high-risk population in Hulunbuir, Inner Mongolia Autonomous Region from 2010 to 2019 and provide evidence for adjusting the brucellosis prevention and control strategy.

  Methods  The stratified sampling surveillance in populations with direct exposures to livestock and its products was conducted in counties of Hulunbuir. Blood samples were taken from the individuals in these counties for preliminary screening by using rose bengal plate agglutination test (RBPT) and for confirmation by using serum agglutination test (SAT). The survey of brucellosis related knowledge awareness was carried out in the above-mentioned populations. The questionnaire included three parts: basic knowledge about brucellosis, risk factors and brucellosis prevention knowledge. Descriptive statistics were used to analyze the infection, incidence and knowledge of brucellosis among high-risk populations. The rate and composition ratio were compared with χ² test, and P<0.05 was considered to indicate significance.

  Results  From 2010 to 2019, a total of 162 539 blood samples were tested in Hulunbuir, in which 8 556 were positive (5.26%). Over time, the positive rate of blood test showed a downward trend. The difference was significant ( χ²=448.824, P<0.05). The positive rate of blood test was 6.19% in pastoral areas, 6.10% in semi-agricultural and semi-pastoral areas, 5.68% in forest areas and 1.95% in cities. The differences among different areas were significant ( χ²=792.139, P<0.05). As for age distribution, the positive persons were mainly young adults between 30 and 59 years old. The infected persons were engaged in breading industry (82.36%), other occupations (including workers, students, unemployed and others) (15.94%), and meat food processing, production, sales and transportation (1.69%). From 2010 to 2019, a total of 170 327 people were surveyed in Hulunbuir, in which 1 525 brucellosis cases were detected. The incidence rate was 0.90%. The incidence showed a fluctuating decreasing trend among different years with statistical significance ( χ²=1 089.662, P<0.05). The awareness rate of brucellosis during 2014–2019 was continuously investigated with a total of 47 187 people being covered and 46 614 valid questionnaires being collected. The total awareness rate was 90.48%, and the total awareness rate showed an upward trend. The differences among years were significant ( χ²=371.421, P<0.05). The awareness rate was 92.95% in cities, 90.48% in forest areas, 89.96% in pastoral areas and 88.47% in semi-agricultural and semi-pastoral areas. The differences were significant ( χ²=123.321, P<0.05).

  Conclusion  The prevention and control strategy for human brucellosis in Hulunbuir has achieved certain progress, but the situation is still serious. Therefore, it is necessary to carry out continuous surveillance for human brucellosis and conduct health education in populations at high risk.