Evaluation of non-vaccination brucellosis control strategies in class II regions using a transmission dynamics model: a case study from Hubei Province.

OBJECTIVE

To develop a transmission dynamics model for brucellosis in Hubei Province and evaluate non-vaccination control strategies.

METHODS

We constructed a SsIs-W-ShEhIhCh(Susceptible sheep - Infected sheep - Environmental bacterial load - Susceptible humans - Exposed humans - Acute infected humans - Chronic infected humans) transmission dynamics model and assessed disease transmissibility through R0 calculation. Four intervention measures (environmental disinfection, improved diagnosis, personal protection, and infected sheep management) were evaluated independently and in combination.

RESULTS

Model fitting showed high consistency with reported cases (R²=0.884, p > 0.999). Disease transmission exhibited three phases: high incidence (2014–2016, R0 = 1.86), decline (2020, R0 = 0.69), and rebound (2023 R0 = 1.76). Direct transmission (sheep-to-human) was the primary driver (78.6%-91.5% of R0). Among single interventions, personal protection yielded the greatest case reduction (93.51% case reduction), followed by infected sheep management (91.02%). The combination of these two measures achieved optimal effectiveness (95.98% case reduction).

CONCLUSION

Brucellosis transmission in Hubei Province is predominantly driven by direct transmission. Comprehensive control strategies should prioritize personal protection and infected sheep management, supplemented by environmental disinfection and improved diagnosis. CLINICAL TRIAL NUMBER: Not applicable.