Skip directly to site content Skip directly to page options Skip directly to A-Z link Skip directly to A-Z link Skip directly to A-Z link
Volume 9, Number 10—October 2003

Antimicrobial Drug-resistant Salmonella Typhimurium (Reply to Helms)

On This Page
Article Metrics

Cite This Article

Read original article.

Read Helms' reply.

In Reply to Helms: In the article by Helms et al., Helms concludes that infections with Salmonella Typhimurium strains resistant to ampicillin, chloramphenicol, streptomycin, sulfonamide, and tetracycline (hereafter referred to as penta-resistant) were associated with higher death rates than infections with non–penta-resistant S. Typhimurium. Helms also concluded that infections with quinolone-resistant (nalidixine-resistant) S. Typhimurium were associated with higher death rates than quinolone-susceptible S. Typhimurium (1).

Table 2 in Helms’ article provides information that enables close scrutiny of this conclusion and comparison of the excess mortality associated with penta-resistant, quinolone-susceptible S. Typhimurium with the excess mortality of non–penta-resistant S. Typhimurium (1). In this letter, the Table is based on the original table. However, two additional comparisons have been added: the p values, which are not based on the data but are approximations based on the parameters in the table.

The conclusion is that only quinolone resistance is associated with excess mortality compared with nonresistant isolates. Penta-resistant, quinolone-susceptible S. Typhimurium has a risk ratio of 2.9 (1.1 to 7.9) compared to the ratio of non–penta-resistant isolates 2.1 (1.5 to 2.9). When these figures are compared, the approximate p value is 0.55, which, of course, is far from being significant. Thus, on the basis of the article by Helms, penta resistance may not pose a greater threat to human health than non–penta resistance. However, the measured effect of penta resistance is achieved by the inclusion of quinolone-resistant S. Typhimurium in the group.




Jan Dahl*Comments to Author 
Author affiliation: *Danish Bacon and Meat Council, Copenhagen, Denmark



  1. Helms  M, Vastrup  P, Gerner-Smidt  P, Mølbak  K. Excess mortality associated with antimicrobial drug-resistant Salmonella Typhimurium. Emerg Infect Dis. 2002;8:4905.PubMedGoogle Scholar




Cite This Article

DOI: 10.3201/eid0910.020716

Related Links


Table of Contents – Volume 9, Number 10—October 2003

EID Search Options
presentation_01 Advanced Article Search – Search articles by author and/or keyword.
presentation_01 Articles by Country Search – Search articles by the topic country.
presentation_01 Article Type Search – Search articles by article type and issue.



Please use the form below to submit correspondence to the authors or contact them at the following address:

Jan Dahl, Danish Bacon and Meat Council, Axeltory 3, 1609 Copenhagen V, Denmark; fax: 4533145756

Send To

10000 character(s) remaining.


Page created: January 07, 2011
Page updated: January 07, 2011
Page reviewed: January 07, 2011
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.