# Quantitative Assessment of the Risk of Introduction of Brucellosis From Ethiopia Into Germany Through the Importation of Small Ruminants

## TL;DR

This study assesses the risk of brucellosis spreading from Ethiopia to Germany through imported small ruminants and finds the risk to be very low.

## Contribution

The study provides a quantitative risk assessment model for brucellosis introduction via animal importation using Monte Carlo simulation.

## Key findings

- The overall probability of introducing brucellosis through sheep and goat imports is 1.276 × 10−7.
- Improving data and using ELISA tests could reduce uncertainty in the risk estimate by up to 49%.

## Abstract

Background: Despite the significant contribution of small ruminants to the improvement of societal livelihood, several factors hamper their production and productivity, chief among which are various production and reproductive diseases. Brucellosis is one of such diseases that causes huge economic loss and imposes trade restrictions.

Methods: A quantitative risk assessment was conducted from July 2023 to January 2024 to evaluate the risk of introduction of brucellosis into Germany via the importation of sheep and goat from Ethiopia. The QRA methods was applied by breaking it into different components, namely, hazard identification and characterization; developing a scenario tree; gathering scientific evidence about the probability of occurrence of these events from published sources; generating mathematical equations taking into account the reliability and variability of the evidences; and, finally, calculating the overall risk of the hazard introduction by running Monte Carlo simulation at 10,000 iterations using @ RISK software, Palisade Co.

Result: The overall probability of introducing brucellosis through the annual importation of sheep and goats from Ethiopia is 1.276 × 10−7 (fifth percentile = 3.07 × 10−7; 95th percentile = 3.08 × 10−7). The results of the sensitivity analysis using the tornado graph showed that the estimate's precision can be improved by 49%, 44%, and 35%, respectively, if the factors that contributed most to the uncertainty were changed by one standard deviation.

Discussion and Conclusion: If the animals (sheep and goat) pass through all mitigations as outlined in the study, the risk of brucellosis introduction into Germany through the importation of small ruminants from Ethiopia is generally low. The uncertainty around the risk estimate could be reduced if more animal-level prevalence data could be obtained and by employing more sensitive diagnostic tests such as ELISA to detect subclinically infected animals. It is recommended that animal health regulators of the two nations work closely to enhance disease diagnosis and surveillance capabilities.