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The effect of heterogeneous infectious period and contagiousness on the dynamics of Salmonella transmission in dairy cattle

  • C. LANZAS (a1), S. BRIEN (a1), R. IVANEK (a1), Y. LO (a1), P. P. CHAPAGAIN (a1) (a2), K. A. RAY (a1), P. AYSCUE (a1), L. D. WARNICK (a1) and Y. T. GRÖHN (a1)...

The objective of this study was to address the impact of heterogeneity of infectious period and contagiousness on Salmonella transmission dynamics in dairy cattle populations. We developed three deterministic SIR-type models with two basic infected stages (clinically and subclinically infected). In addition, model 2 included long-term shedders, which were defined as individuals with low contagiousness but long infectious period, and model 3 included super-shedders (individuals with high contagiousness and long infectious period). The simulated dynamics, basic reproduction number (R0) and critical vaccination threshold were studied. Clinically infected individuals were the main force of infection transmission for models 1 and 2. Long-term shedders had a small impact on the transmission of the infection and on the estimated vaccination thresholds. The presence of super-shedders increases R0 and decreases the effectiveness of population-wise strategies to reduce infection, making necessary the application of strategies that target this specific group.

Corresponding author
*Author for correspondence: Dr C. Lanzas, Department of Population Medicine and Diagnostic Science, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA. (Email:
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1. Mead PS, et al. Food-related illness and death in the United States. Emerging Infectious Diseases 1999; 5: 607625.
2. Dechet AM, et al. Outbreak of multidrug-resistant Salmonella enterica serotype Typhimurium definitive type 104 infection linked to commercial ground beef, northeastern United States, 2003–2004. Clinical Infectious Diseases 2006; 42: 747752.
3. Olsen SJ, et al. Multidrug-resistant Salmonella typhimurium infection from milk contaminated after pasteurization. Emerging Infectious Diseases 2004; 10: 932935.
4. Cody SH, et al. Two outbreaks of multidrug-resistant Salmonella serotype Typhimurium DT104 infections linked to raw-milk cheese in northern California. Journal of the American Medical Association 1999; 281: 18051810.
5. Gupta A, et al. Emergence of multidrug-resistant Salmonella enterica serotype Newport infections resistant to expanded-spectrum cephalosporins in the United States. Journal of Infectious Diseases 2003; 188: 17071716.
6. Helms M, et al. Excess mortality associated with antimicrobial drug-resistant Salmonella typhimurium. Emerging Infectious Diseases 2002; 8: 490495.
7. Martin LJ, et al. Increased burden of illness associated with antimicrobial-resistant Salmonella enterica serotype Typhimurium infections. Journal of Infectious Diseases 2004; 189: 377384.
8. Humphrey T. Science and society – Salmonella, stress responses and food safety. Nature Reviews Microbiology 2004; 2: 504509.
9. Wray C, et al. A three-year study of Salmonella dublin infection in a closed dairy herd. Veterinary Record 1989; 124: 532537.
10. Anderson RJ, et al. Epidemiologic and biological characteristics of salmonellosis in three dairy herds. Journal of the American Veterinary Medical Association 2001; 219: 310322.
11. Cobbold RN, et al. Long-term persistence of multi-drug-resistant Salmonella enterica serovar Newport in two dairy herds. Journal of the American Veterinary Medical Association 2006; 228: 585591.
12. Anderson RM, May RM. Infectious Diseases of Humans: Dynamics and Control. Oxford, UK: Oxford University Press, 1992.
13. Xiao YN, et al. Understanding the dynamics of Salmonella infections in dairy herds: a modelling approach. Journal of Theoretical Biology 2005; 233: 159175.
14. Xiao Y, et al. A semi-stochastic model for Salmonella infection in a multi-group herd. Mathematical Biosciences 2006; 200: 214233.
15. Chapagain PP, et al. A mathematical model of the dynamics of Salmonella Cerro infection in a US dairy herd. Epidemiology and Infection. Published online: 20 April 2007. doi: 10.1017/S0950268807008400.
16. De Jong H, Ekdahl MO. Salmonellosis in calves – the effect of dose rate and other factors on transmission. New Zealand Veterinary Journal 1965; 13: 5967.
17. Wray C, Davies RH. Salmonella infections in cattle. In: Wray C, Wray A eds. Salmonella in Domestic Animals. Wallingford, UK: CABI Publishing, 2000, pp. 169190.
18. Huston CL, Wittum TE, Love BC. Persistent fecal Salmonella shedding in five dairy herds. Journal of the American Veterinary Medical Association 2002; 220: 650655.
19. Begon M, et al. A clarification of transmission terms in host-microparasite models: numbers, densities and areas. Epidemiology and Infection 2002; 129: 147153.
20. Jones PW, Watson PR, Wallis TS. Salmonellosis. In: Andrews AH eds. Bovine Medicine: Disease and Husbandry of Cattle Oxford, UK: Blackwell Publishing, 2004, pp. 215230.
21. Kabagambe EK, et al. Risk factors for fecal shedding of Salmonella in 91 US dairy herds in 1996. Preventive Veterinary Medicine 2000; 43: 177194.
22. Warnick LD, et al. Effect of previous antimicrobial treatment on fecal shedding of Salmonella enterica subsp enterica serogroup B in New York dairy herds with recent clinical salmonellosis. Preventive Veterinary Medicine 2003; 56: 285297.
23. Wray C, Sojka WJ. Experimental Salmonella typhimurium infection in calves. Research in Veterinary Science 1978; 25: 139143.
24. Warnick LD, et al. Duration of fecal shedding following clinical salmonellosis in dairy cattle. In: International Symposium on Veterinary Epidemiology and Economics. Cairns, Australia, 2006.
25. Fossler CP, et al. Herd-level factors associated with isolation of Salmonella in a multi-state study of conventional and organic dairy farms – I. Salmonella shedding in cows. Preventive Veterinary Medicine 2005; 70: 257277.
26. Low JC, et al. Rectal carriage of enterohemorrhagic Escherichia coli O157 in slaughtered cattle. Applied and environmental microbiology 2005; 71: 9397.
27. Matthews L, et al. Heterogeneous shedding of Escherichia coli O157 in cattle and its implications for control. Proceedings of the National Academy of Sciences USA 2006; 103: 547552.
28. Ray KA. Epidemiology of antimicrobial resistant Salmonella on dairy farms in the northeast and midwest USA (Dissertation). Ithaca, NY: Cornell University, 2007, 225 pp.
29. Diekmann O, Heesterbeek JAP. Mathematical Epidemiology of Infectious Diseases: Model Building, Analysis and Interpretation. Chichester, UK: John Wiley & Sons, 2000.
30. van den Driessche P, Watmough J. Reproduction numbers and sub-threshold endemic equilibria for compartmental models of disease transmission. Mathematical Biosciences 2002; 180: 2948.
31. House JK, et al. Evaluation of an autogenous Salmonella bacterin and a modified live Salmonella serotype choleraesuis vaccine on a commercial dairy farm. American Journal of Veterinary Research 2001; 62: 18971902.
32. Robertsson JA, et al. Salmonella typhimurium infection in calves – protection and survival of virulent challenge bacteria after immunization with live or inactivated vaccines. Infection and Immunity 1983; 41: 742750.
33. Helton JC, Davis FJ. Illustration of sampling-based methods for uncertainty and sensitivity analysis. Risk Analysis 2002; 22: 591622.
34. Helton JC, Davis FJ. Latin hypercube sampling and the propagation of uncertainty in analyses of complex systems. Reliability Engineering & System Safety 2003; 81: 2369.
35. Matthews L, et al. Super-shedding cattle and the transmission dynamics of Escherichia coli O157. Epidemiology and Infection 2006; 134: 131142.
36. Lloyd-Smith JO, et al. Superspreading and the effect of individual variation on disease emergence. Nature 2005; 438: 355359.
37. Woolhouse MEJ, et al. Heterogeneities in the transmission of infectious agents: implications for the design of control programs. Proceedings of the National Academy of Sciences USA 1997; 94: 338342.
38. Nielsen LR, Toft N, Ersboll AK. Evaluation of an indirect serum ELISA and a bacteriological faecal culture test for diagnosis of Salmonella serotype dublin in cattle using latent class models. Journal of Applied Microbiology 2004; 96: 311319.
39. Mastroeni P, et al. Salmonella: immune responses and vaccines. Veterinary Journal 2001; 161: 132164.
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