Salmonella survival

Salmonella. Different Salmonella species were found to vary widely in radiation sensitivity. Salmonellae surviving irradiation were able to grow on sea foods incubated at 22°C. but actually declined in number on sea foods held at 11° and 5°C. 

LiCari, J.J. and Potter, N.N. Salmonella survival during spray drying and subsequent handling of skimmilk powder. 11. Effects of drying conditions, /. Dairy Scl, 53, 871, 1970. 

Fur has a regulatory influence on the acid-shock response in E. coli and Salmonella. The acid-response reactions are important for the cells to survive when they pass the acidic gut. In Salmonella, a Fur-dependent, but iron-independent, regulation of acid-response genes is observed. Certain point mutations of Fur (e.g. H90R) do not respond to iron, but are able to regulate an acid-response gene (Foster, 2000). Unfortunately, the functions of the Fur-dependent gene products in acid response are not known. 

Himathongham S, Bahari S, Riemann H and Cliver D (1999), Survival of Escherichia coli 0157 H/ and Salmonella typhimurium in cow manure and cow manure slurry , FEMS Microbiology Letters, 178, 251-257. 

ANDREWS, DA., MAWER, S L and MATTHEWS, P J. (1983). Survival of salmonellae in sewage sludge injected into soil. Effluent and Water Treatment J, February 1983, 72-74. 

Campylobacter is notoriously fastidious and has very specific growth conditions. The bacterium can survive for short periods outside the host environment but not to the same extent as Salmonella and E. coli (Alter and Scherer, 2006 Garenaux et al., 2008 Mihaljevic et al., 2007). However, despite such fragility, C. jejuni, and to a lesser extent Campylobacter coli, has been the main cause of gastroenteritis for several years 0anssen et al., 2008). This is likely due to the low infectious dose (<500 cells) required to cause symptoms in susceptible hosts and the high carriage rate in livestock (Ozcakir, 2007). 

E. coli 0157 H7 can survive in high moisture content bovine manure for over 70 days at 5 °C that compared to 49 days at 30 °C (Semenov et al., 2007). The persistence of Salmonella in manure is also favored under low temperature and high moisture conditions (Mannion et al., 2007). However, survival of both pathogens in manure slurry is restricted to a maximum of 10 days (Cote et al, 2006). Laboratory studies on E. coli 0157 H7 and S. Typhimur-ium in cow manure and cow slurry indicated that death rate is a function of temperature and depth in the storage container (Himathongkham et al.,... 

The survival of common manure-derived pathogens in soils was reviewed by Nicholson et al. (2005), who concluded that maximum survival ranged from 45 to 100 days with an average log reduction of 1.94 days for E. coli 0157, L. monocytogenes, Salmonella, and C. jejuni. The time for a 1 — log reduction in C. parvum levels, however, varied between 8 and 31 days. 

The association of human pathogens with biofilms formed by resident epithytes is considered to enhance survival on leaf surfaces. It has been estimated that 10-40% of the total bacteria on the surface of parsley and broad-leaf endive are associated with biofilms (Lindow and Brandi, 2003). However, studies performed with E. coli 0157 H7 or Salmonella would suggest that bacterial cells tend to aggregate between the grooves of epidermal cells rather than associate with biofilm structures (Warriner et al, 2003a). 

There have been relatively few studies with regard to the survival of human pathogens on the surface of leaves over long periods. However, studies using C. jejuni, E. coli 0157 H7, and Salmonella would suggest that this is significantly lower compared to the rhizosphere (Brandi and Amundson, 2008 Brandi et al., 2004). Nevertheless, as previously outlined, contamination of edible leaves immediately prior to harvest would represent a significant food safety hazard. 

Duffy, E. A., Cisneros-Zevallos, L., Castillo, A., Pillai, S. D., Ricke, S. C., and Acuff, G. R. (2005). Survival of Salmonella transformed to express green fluorescent protein on Italian parsley as affected by processing and storage. /. Food Prot. 68, 687-695. 

Guo, X., Chen, J. R., Brackett, R. E., and Beuchat, L. R. (2001). Survival of Salmonellae on and in tomato plants from the time of inoculation at flowering and early stages of fruit development through fruit ripening. Appl. Environ. Microbiol. 67,4760M764. 

Mannion, C., Lynch, P. B., Egan, J., and Leonard, F. C. (2007). Seasonal effects on the survival characteristics of Salmonella Typhimurium and Salmonella Derby in pig slurry during storage. J. Appl. Microbiol. 103,1386-1392. 

Santo Domingo, J. W., Harmon, S., and Bennett, J. (2000). Survival of Salmonella species in river water. Curr. Microbiol. 40,409-417. 

Salmonella Contaminant Improper processing of food allows Salmonella from intestinal tract to survive the most common cause of gastroenteritis... 

Therapeutic vaccines were tested in BALB/c mice bearing TA3-Ha mammary carcinoma. The treatment consisted of 4 subcutaneous injections, at 3-6 days intervals, of Detox [a commercial preparation of cell wall skeletons from Mycobacterium phlei and non-toxic monophosphoryl lipid A from Salmonella minnesota (S. minnesota) in squalane oil and Tween 80 from Ribi Immunochemical research, Montana, USA] mixed with Thomsen-Friedenreich (TF) antigen coupled with KLH (Keyhole Limpet Hemocyanin) performed 5 days after the tumor cell injection. This vaccination achieved the survival of 25 % of the mice. Pretreatment of mice with cyclophosphamide in order to inhibit any suppressive response, increased survival to 50 % when the treatment began 5 days after tumor cell injection, and to 90 % when the treatment began 2 days after tumor cell injection. Both antibody as well as delayed-... 

---