Salmonella typhimurium DT104, Italy.To the Editor: The recent article by Helms et al. described the distribution of Salmonella enterica serovar Typhimurium definitive page type 104 (DT104) infections in 29 countries from 1992 to 2001 (1). Results from Italy were not presented because routine phage typing was not performed before 2001. Since 2002, circulation of S. Typhimurium phage types has been monitored by the laboratory-based surveillance system Enter-net Italia, which was coordinated by Istituto Superiore di Sanita as part of the European network for the surveillance of foodborne infections (2). From 2000 to 2004, S. Typhimurium accounted for [approximately equal to] 40% of all human Salmonella isolates each year. Since 2002, [approximately equal to] 20% of the S. Typhimurium isolates were identified as DT104, and all had a pentavalent pentavalent
having a valence of five.
pentavalent antimony compounds
pentavalent organic arsenicals
includes the pharmaceuticals arsanilic acid, roxarsone, nitarsone. See also organic arsenical. resistance pattern (resistance to ampicillin ampicillin (ăm'pĭsĭl`ĭn), a penicillin-type antibiotic that is effective against both gram-negative microorganisms and gram-positive microorganisms such as Escherichia coli. , chloramphenicol chloramphenicol (klōr'ămfĕn`əkŏl'), antibiotic effective against a wide range of gram-negative and gram-positive bacteria (see Gram's stain). It was originally isolated from a species of Streptomyces bacteria. , streptomycin streptomycin (strĕp'tōmī`sĭn), antibiotic produced by soil bacteria of the genus Streptomyces and active against both gram-positive and gram-negative bacteria (see Gram's stain), including species resistant to other , sulfonamides Sulfonamides Definition
Sulfonamides are medicines that prevent the growth of bacteria in the body.
Sulfonamides are used to treat many kinds of infections caused by bacteria and certain other microorganisms. , and tetracycline tetracycline (tĕ'trəsī`klēn), any of a group of antibiotics produced by bacteria of the genus Streptomyces. They are effective against a wide range of Gram positive and Gram negative bacteria, interfering with protein ) (3). Although the results reported by Helms et al. (1) refer to a different period (1992-2001), the Italian data are similar to those from many other countries in northern and western Europe.
According to the Colindale scheme for phage typing ( and L.R. Ward, pers. comm.), numerous distinguishable DT104 subtypes can be identified as DT104 A, B, C, H, and L. Most (90%) S. Typhimurium DT 104 strains isolated during the last 2 years belonged to subtype DT104L.
Emergence of phage subtype DT104A was identified in June 2004 during an outbreak of salmonellosis salmonellosis (săl'mənĕlō`sĭs), any of a group of infectious diseases caused by intestinal bacteria of the genus Salmonella, in Rome. This subtype had never been previously identified in Italy. All DT104A isolates were susceptible to the Enter-net panel of antimicrobial drugs (2), a feature unusual for S. Typhimurium (5). A total of 63 cases were confirmed; 61 were from Rome, and 2 were from a neighboring region. All isolates had similar pulsed-field gel electrophoretic profiles when analyzed with the Salm-gene protocol (6). Since the outbreak, 1 additional human isolate of DT 104A was identified from a resident of the same neighboring region. This isolate was also susceptible to the panel of antimicrobial drugs. A fermented pork salami was epidemiologically implicated as the vehicle of infection. No microbiologic evidence was found because no food samples were available when the outbreak was recognized.
The incidence of DT104 in Italy has remained stable from 2002 through 2004. However, emergence of subtype DT104A during a recent outbreak highlights the need for subtyping in identifying communitywide outbreaks and in monitoring changing subtype patterns.
(1.) Helms M, Ethelberg S, Molbak K, DT104 Study Group. International Salmonella Typhimurium DT104 infections, 1992-2001. Emerg Infect Dis. 2005;11:859-67.
(2.) Enter-net. International surveillance network for the enteric infections Salmonella and VTEC VTEC
verocytotoxin producing Escherichia coli. O157. [cited 2006 May 12]. Available from http://www.hpa.org.uk/hpa/ inter/enter-net_menu.htm
(3.) Busani L, Graziani C, Battisti A, Franco A, Ricci A, Vio D, et al. Antibotic resistance in Salmonella enterica serotypes Typhimurium, Enteritidis and Infantis from human infections foodstuffs foodstuffs npl → comestibles mpl
foodstuffs npl → denrées fpl alimentaires
foodstuffs food npl → and farm animals in Italy. Epidemiol Infect. 2004;132:245-51.
(4.) Anderson ES, Ward LR, De Saxe MJ, Old DC, Barker R, Duguid JP. Bacteriophage-typing designations of Salmonella Typhimurium. J Hyg (Lond). 1977;78: 297-300.
(5.) Malorny B, Schroeter A, Bunge C, Helmuth R. Prevalence of Escherichia coli O157:H7 prophage-like sequences among German Salmonella enterica serotype serotype /se·ro·type/ (ser´o-tip) the type of a microorganism determined by its constituent antigens; a taxonomic subdivision based thereon.
v. Typhimurium phage types and their use in detection of phage type DT104 by polymerase chain reaction polymerase chain reaction (pŏl`ĭmərās') (PCR), laboratory process in which a particular DNA segment from a mixture of DNA chains is rapidly replicated, producing a large, readily analyzed sample of a piece of DNA; the process is . Vet Microbiol. 2002;87:253-65.
(6.) Peters TM, Maguire C, Threlfall E J, Fisher IST, Gill N, Gatto AJ. on behalf of the Salm-gene project participants. The Salm-gene project a European collaboration for DNA fingerprinting for food-related salmonellosis. Euro Surveill. 2003;8:46-50.
Address for correspondence: Amy Cawthorne, European Programme for Intervention Epidemiology Training, Istituto Superiore di Sanita, Centro Nazionale di Epidemiologia, Sorveglianza e Promozione della Salute, Reparto di Epidemiologia delle Malattie Infettive, Viale Regina Elena 299, 00161 Rome, Italy; email: email@example.com
Amy Cawthorne,* Pasquale Galetta,* Marco Massari,* Anna Maria Dionisi,* Emma Filetici,* and Ida Luzzi*
* Istituto Superiore di Sanita, Rome, Italy