Abstract

This work reports a quantitative risk assessment of human salmonellosis linked to the consumption of ground beef patties in France. The risk assessment was based on data on the frequency, concentration and inactivation of Salmonella in ground beef. Different distributions were assumed for parameters of the model and Monte Carlo simulations were used to model the process and to quantify the resulting risk for public health. The probability of ground beef batches contamination was estimated to be 100% after 2000 iterations with an expected percentage of ground beef batch with patties contamination less than 1, 6, 12, and 18 percent were 22.5%, 52%, 69% and 95%, respectively. About 93% of ground beef patties (55.7 million out of 60 million patties) were expected not to be contaminated. The simulated concentration of Salmonella in a typical ground beef patty serving of 100 g before cooking ranged from 0 to 1.4 x 10⁶ Salmonella cells with a median of 0 cells. The expected percentage of ground beef patties with contamination greater than 5, 10 and 100 Salmonella cells were 29%, 17% and 0.02%, respectively. For 10 million servings of 100 g, the expected number of cases of salmonellosis predicted by the model is in average 7 and 8 for fat content 7% and 24% respectively. The risk of salmonellosis per 100 g serving ranged from 0 to 2.33E-06 dependent on the type of cooking and the fat content. The risk of salmonellosis was closed to zero when the 100 g serving ground beef patties were consumed well done. The relative risk of getting salmonellosis from the consumption of rare ground beef patties is 312, 61 times higher for fat content 7% and 24% respectively comparing to the consumption of well done patties. There are 35 batches with at least one case out of 2000 batches (1.8%). 15 of them have 2 cases or more (0.75%).