Trends of reported human cases of brucellosis, Kingdom of Saudi Arabia, 2004-2012.

Human brucellosis is an important zoonotic disease and is especially concerning in the Kingdom of Saudi Arabia (KSA), where livestock importation is significant. We analyzed reported human brucellosis disease trends in KSA over time to help policymakers understand the magnitude of the disease and guide the design of prevention and control measures. By using data from the national registry from 2004 to 2012, we calculated the cumulative numbers by age group and months. Trends of incidence rates (IRs) by gender, nationality, and region were also calculated. We found that there was a greater number of cases (19,130) in the 15-44 years age group than in any other age group. The IRs significantly decreased from 22.9 in 2004 [95% confidence interval (CI)=22.3, 23.5] to 12.5 in 2012 (95% CI=12.1, 13). Males had a significantly greater IR than females. Most cases were reported during spring and summer seasons. The IR of Saudi citizens was significantly greater than that of non-Saudis, but this difference reduced over time. The IRs of Al-Qassim, Aseer, and Hail were in the highest 25th percentile. Young, male Saudi citizens living in highly endemic areas were at greatest risk of acquiring brucellosis. We recommend vaccinating susceptible animals against brucellosis and increasing the public's awareness of preventive measures.