Table 4.

Input parameters for the model to assess the risk of CPE introduction into Dutch livestock farms.

Input *	Description	Value Distribution **	Value in Sensitivity Analysis	References
$N_{intro}$	Expected annual number of farms on which CPE is introduced
$N_{co{l}_s}$	Number of farms exposed to CPE-colonized sources s (imported livestock (A), livestock feed (F), companion animals (C), farm workers being hospitalized (H), and farm workers traveling abroad (T))
$N_s$	Number of farms in contact with people, import animals, companion animals, and livestock feed
$P_{CP{E}_s}$	Probability of sources exposed to farm are colonized/contaminated with CPE
$P_{CPE}{}_{batch}$	Probability that an individual farm receives at least one batch of feed contaminated with CPE
$N_{batch}$	Annual number of feed batches received by a farm
$P_{CP{E}_{feed}}$	Probability that a batch of feed is contaminated with CPE
$N_C$	Number of farms with companion animals
$N_H$	Number of farm workers/vets hospitalized
$N_{T_k}$	Number of farm workers/vets returning from abroad
$CP{E}_{ing}{}_s$	Total number of CPE E. coli bacteria ingested by the animals on an exposed farm
$CP{E}_{concF}$	Total number of CPE E. coli (cfu/g) in contaminated animal feed
$CP{E}_{gramC}$	Total number of CPE E. coli (cfu/g) in companion animal feces
$CP{E}_{hand}$	Total number of CPE E. coli (cfu) remaining on a farm worker’s hands after hand washing
$P$	Probability of a single CPE bacterium colonizing an animal’s gut
$N_{imp}$	Annual number of imported broilers, parent broilers, piglets, breeding pigs, and veal calves from EU member states j to farm type i in The Netherlands	Supplementary File S7	Yes	[41,48]
$se$	CPE surveillance sensitivity	0.85	Yes	[14]
$P_{CP{E}_{\mathrm{A}}}$ $P_{CP{E}_{NL}}$	CPE prevalence in livestock i in country j CPE prevalence in hospitalized patients in The Netherlands	Beta (α/se, β) (values of beta distribution in EFSA reference) Beta (8/se, 6676)	Yes	[9,10,24]
$P_{CP\mathrm{E}}$	CPE prevalence in hospital patients in region m	Beta (α/se, β) (values of beta distribution are in Table S5)	Yes	[63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78,79,80,81,82,83]
$C_{com: cli}$	Ratio of ESBL in the community versus ESBL in a clinical setting	0.79	N	Table S3
$P_{e{c}_{feed}}$	Prevalence of E. coli-contaminated feed in compound cattle feed	Beta (59, 46)	Yes	[23]
$P_{e{c}_{NL}}$	Prevalence of E. coli in Dutch residents	Beta (159,620, 280,677)	Yes	[55]
$N_{siz\mathrm{e}}$: broiler $N_{siz\mathrm{e}}$: piglet $N_{siz\mathrm{e}}$: breeding pig $N_{siz\mathrm{e}}$: veal calf	Number of livestock i per shipment	Pert (45,00,47,000, 55,000) Pert (100, 260,300) Pert (65, 80, 95) Pert (30, 150, 200)	Yes	[29]
$N_{far\mathrm{m}}\mathrm{and}$ $N_{animal}$	Total number of farm types i and total number of animals i in The Netherlands	Table S5	Yes	[41]
$N_K$	Total number of farm workers and veterinarians in The Netherlands	Table S5	Yes	[41]
$c_{\mathrm{a}}$	The average grams of feed consumed by livestock i per day	Table S5	Yes	[84,85,86]
$V_{batch}$	The average grams of feed delivered to a farm derived from the volume of a standard transport truck	Pert (3 × 106, 16 × 106, 3 × 107)	Yes	[29]
$Ecol{i}_{conc\mathrm{F}}:$ broiler $Ecol{i}_{conc\mathrm{F}}$: fattening pig $Ecol{i}_{concF}$: breeding pig $Ecol{i}_{concF}$: veal calf	Concentrations of E. coli in feed components following minimum rejection limit by GMP+ (cfu/g)	11.8 11.8 14.3 7.3	Yes	[54]
$Ecol{i}_{hand}$	The amount of E. coli remaining on a farm worker’s hands after toilet use and subsequent hand washing (cfu)	Log-normal (63, 5.02)	Yes	[28]
$ESB{L}_{gramFec}$(cfu/g)	Number of E. coli (cfu) in a gram of healthy companion animal’s feces	Normal (70, 35)	Yes	[87]
$P_{CPE:EC}$ $P_{CPE:ESBL}$	Proportion of E. coli carrying CPE genes and proportion of ESBL E. coli carrying CPE genes	0.00004 0.00424	N	[37]
$ID50$: broiler $ID50$: pig and veal calf	Infectious dose of ESBL E. coli at which, on average, 50% of livestock species i are colonized (cfu)	Log-normal (5, 5) Log-normal (4695, 9187)	Yes	[56,88,89]
$P_{far{m}_C}$	Proportion of farms that have companion animals	Beta (298, 148)	Yes	[56]
$W_{fec}$ (grams)	Grams of feces defecated by a companion animal in one defecation	Normal (70, 35)	Yes	[58]
$N_{el{i}_C}$ $N_{el{i}_H}$	The average number of defecations by companion animals and humans per day	Pert (1, 2, 5) Uniform (1,3)	Yes	[57] Assumption
$T_{CP{E}_C}$ $T_{CP{E}_H}$	Colonization duration of CPE in companion animals and humans (days)	Pert (0, 120, 180) Pert (1, 30, 365)	Yes	[60,90]
${\mathrm{P}}_{barnC}$ $P_{barnH}$: farm worker $P_{barnH}$: veterinarian	Proportion of day a companion animal, farm worker, and veterinarian spent in the barns	0 0.33 0.005	Yes	Assumption
$C_{tranA}$ $C_{tranE}$	Proportion of Acinobacter transferred from fomite to finger (A) and from finger to fomite (E)	Log-normal (0.24, 0.14) Log-normal (0.06, 0.06)	Yes	[59]
$P_T$	The probability of Dutch travelers visiting 16 world regions in 2013	Table S5	Yes	[41]
$P_{holida\mathrm{y}}$: broiler and pig farm worker $P_{holida\mathrm{y}}$: veal calf farm worker $P_{holida\mathrm{y}}$: veterinarian	Probability of farm worker on farm i taking holiday abroad annually	0.53 0.33 0.64	Yes	[41,61,91]
$Av{g}_{farmers}$	The average number of farm workers in all farm types	Pert (1, 2, 4)	Yes	Assumption
$P_{admit}$ $P_{admit}{}_{NL}$	Probability of hospital admission while traveling overseas and in The Netherlands	0.04 0.054	Yes	[41,90,92]

Footnotes: * Type of farm is indicated by subscript i and source country by j. ** Parameters for input distributions given in brackets: beta (α,β), where α equals the number of positives plus one, and β the number of negatives plus one; log-normal (mean, SD); normal (mean, SD); pert (minimum, most likely, maximum); uniform (minimum, maximum). Parameters with an empty Value Distribution are parameters calculated from the raw input.