Characterisation of the acid sensitivity of Salmonella typhimurium phage type DT104
Karakterisering van de zuurgevoeligheid van Salmonella typhimurium faagtype DT104
26 May 2012, PDF |
18 pages |
de Jonge R, van Leusden FM, Dufrenne JB, Ritmeester WS, Delfgou-van Asch EHM, van Pelt W
RIVM Report 149106005
Reports in the UK on human isolates of Salmonella typhimurium indicate that the number of isolates had increased from 87 in 1989 to over 3600 in 1996. They were all shown to be resistant to at least five antibiotics. In the Netherlands the number of cases of acute gastro-intestinal disease caused by S. typhimurium DT104 increased from 10 in 1985 to 163 in 1997. S. typhimurium DT104 is present in all types of animals used for production. It causes severe disease in cattle and pigs. Human infections due to this foodborne type of salmonella seem to be more severe than infections due to other types of S. typhimurium. Following oral ingestion and passage through the stomach, S. typhimurium invades epithelial cells of the small intestine. S. typhimurium DT104, however, is not shown to be more invasive than other salmonellas. The more severe symptoms associated with an infection with S. typhimurium DT104 might be dose-related. If S. typhimurium DT104 is shown to be more acid-resistant, the number of cells surviving the stomach is higher. The results presented in this report clearly show that some isolates of Salmonella typhimurium phage type DT104 are resistant to low-pH environments.