Salmonella Derby clonal spread from pork.The genetic diversity of the Derby serotype serotype /se·ro·type/ (ser´o-tip) the type of a microorganism determined by its constituent antigens; a taxonomic subdivision based thereon. se·ro·type n. See serovar. v. of Salmonella enterica Salmonella enterica is a rod shaped, flagellated, Gram-negative bacterium, and a member of the genus Salmonella.[1] Serovars S. enterica has an extraordinarily large number of serovars in Spain was examined by pulsed-field gel electrophoresis gel electrophoresis n. Electrophoresis performed in a gel composed of agarose, polyacrylamide, or starch. (PFGE PFGE Pulsed-Field Gel Electrophoresis ). Out of 24 identified PFGE profiles, a major clone was detected in 19% of strains from humans, 52% from food, and 62% from swine. This clone (clone 1) was isolated from pork products, suggesting swine as its source. ********** Salmonellosis salmonellosis (săl'mənĕlō`sĭs), any of a group of infectious diseases caused by intestinal bacteria of the genus Salmonella, , a major public health concern worldwide, is one of the most common causes of human gastroenteritis gastroenteritis: see enteritis. gastroenteritis Acute infectious syndrome of the stomach lining and intestines. Symptoms include diarrhea, vomiting, and abdominal cramps. . It is caused by the ingestion ingestion /in·ges·tion/ (-chun) the taking of food, drugs, etc., into the body by mouth. in·ges·tion n. 1. The act of taking food and drink into the body by the mouth. 2. of contaminated contaminated, v 1. made radioactive by the addition of small quantities of radioactive material. 2. made contaminated by adding infective or radiographic materials. 3. an infective surface or object. food because of a failure to control Salmonella infection in animal husbandry animal husbandry, aspect of agriculture concerned with the care and breeding of domestic animals such as cattle, goats, sheep, hogs, and horses. Domestication of wild animal species was a crucial achievement in the prehistoric transition of human civilization from . Its carriers are swine, poultry, and cattle, along with eggs, milk, and fresh seafood (1). Salmonella in pork carcasses is a result of fecal contamination during slaughtering and processing. In this case, the carrier swine is the main initial source of contamination (2,3), and bacteria are usually located in the pharynx pharynx (fâr`ĭngks), area of the gastrointestinal and respiratory tracts which lies between the mouth and the esophagus. In humans, the pharynx is a cone-shaped tube about 4 1-2 in. (11.43 cm) long. , lymph nodes Lymph nodes Small, bean-shaped masses of tissue scattered along the lymphatic system that act as filters and immune monitors, removing fluids, bacteria, or cancer cells that travel through the lymph system. , stomach, and feces (4). During 2002, Salmonella enterica subsp. enterica serotype Derby was the second and sixth most common Salmonella serotype in clinical and nonclinical nonhuman sources, representing 24.0% and 3.7% of isolates reported to the Centers for Disease Control and Prevention Centers for Disease Control and Prevention (CDC), agency of the U.S. Public Health Service since 1973, with headquarters in Atlanta; it was established in 1946 as the Communicable Disease Center. and the National Veterinary Service, respectively (5). The frequency of S. Derby among isolates from animals received at the Spanish National Reference Laboratory for Salmonella and Shigella shigella Any of the rod-shaped bacteria that make up the genus Shigella, which are normal inhabitants of the human intestinal tract and can cause dysentery, or shigellosis. Shigellae are gram-negative (see gram stain), non-spore-forming, stationary bacteria. S. (LNRSSE) was higher than in previous years because of isolates received from swine farms. The incidence or S. Derby in Spain has remained stable in isolates of human and food origin, accounting for 0.55% and 2.5%, respectively, of Salmonella recovered from these sources from 1997 to 2003 (M.A. Echeita, unpub. data). The persistence and clonal survival of S. Derby in swine populations and in closed environments and the role of pork and pork products as sources of outbreaks in humans have been described previously (6-8). S. Derby is one of the most common serotypes of Salmonella in swine. It accounted for 24.2% of the serotypes at 3 nurseries and 9 finishing farms of 2 commercial swine production companies in North Carolina North Carolina, state in the SE United States. It is bordered by the Atlantic Ocean (E), South Carolina and Georgia (S), Tennessee (W), and Virginia (N). Facts and Figures Area, 52,586 sq mi (136,198 sq km). Pop. (9), and for 37.1% at 5 swine-finishing units in Quebec, Canada (10). To obtain epidemiologic insights into human acquisition of the S. Derby serotype compared with swine-related strains, antimicrobial susceptibility profiles were obtained and genetic characterization by pulsed-field gel electrophoresis (PFGE) was conducted in strains isolated from humans, food, and the environment. Unlike more common serotypes such as Enteritidis or Typhimurium, this serotype has not been subjected to intensive molecular epidemiologic studies. The Study A total of 110 S. Derby isolates collected during a 3-year period (2000-2002) were studied. Forty-seven of these isolates (LNRSSE group) were submitted by 34 Spanish laboratories and had the following origins: humans (n = 16), food (n = 23), ill animals (n = 6), and environmental sources (n = 2), as shown in Table 1. The remaining 63 isolates (swine group) were obtained from the stools and mesenteric mesenteric /mes·en·ter·ic/ (-ter´ik) pertaining to the mesentery. mesenteric pertaining to or emanating from the mesentery. lymph nodes of 48 swine slaughtered at 4 swine operations (A, B, C, and D) and 6 finishing units (units 1-6) (Table 2) in Spain. The swine reared on these farms shared the same feed supply and had similar genetic backgrounds. The isolates were screened for antimicrobial resistance by the disk diffusion method (Clinical and Laboratory Standards Institute, Wayne, PA, USA). All isolates were susceptible to amoxicillin-clavulanate, cephalothin cephalothin a first generation cephalosporin antibiotic. Sensitive organisms include many penicillin-resistant staphylococci. cephalothin Cefalotin® Infectious disease A parenteral semisynthetic derivative of cephalosporin C, and 3 , cefuroxime, cefotaxilne, ceftriaxone ceftriaxone /cef·tri·ax·one/ (cef?tri-ak´son) a semisynthetic, ß–resistant, third-generation cephalosporin effective against a wide range of gram-positive and gram-negative bacteria, used as the sodium salt. , cefoxitin, imipenem, ciprofloxacin ciprofloxacin /cip·ro·flox·a·cin/ (sip?ro-flok´sah-sin) a synthetic antibacterial effective against many gram-positive and gram-negative bacteria; used as the hydrochloride salt. cip·ro·flox·a·cin n. , and enrofloxacin. All strains but 1 were resistant to spectinomycin spectinomycin /spec·ti·no·my·cin/ (spek?ti-no-mi´sin) an antibiotic derived from Streptomyces spectabilis, used as the hydrochloride salt in the treatment of gonorrhea. and had variable resistances to the remaining antimicrobial agents Antimicrobial agents Chemical compounds biosynthetically or synthetically produced which either destroy or usefully suppress the growth or metabolism of a variety of microscopic or submicroscopic forms of life. tested (Tables 1 and 2). A total of 70% and 85.7% of the isolates in the LNRSSE and swine groups were resistant to 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 , 36.6% and 85.7% to 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 , 33.3% and 71.4% to sulfonamides Sulfonamides Definition Sulfonamides are medicines that prevent the growth of bacteria in the body. Purpose Sulfonamides are used to treat many kinds of infections caused by bacteria and certain other microorganisms. , 23.3% and 50% 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. and ticarcillin, 16.6% and 42.8% to cotrimoxazole, and 13.3% and 7.1% to nalidixic acid nalidixic acid /nal·i·dix·ic ac·id/ (nal-i-dik´sik) a synthetic antibacterial agent used in the treatment of genitourinary infections caused by gram-negative organisms. na·li·dix·ic acid n. , respectively (Tables 1 and 2). Phenotypes in both groups were most commonly resistant to tetracycline and sulfamethoxazole/tetracycline. Multiple drug resistance (resistance to [greater than or equal to] 4 drugs), was observed in 23.3% of LNRSSE isolates and 64.3% of swine isolates. In addition, the MICs for nalidixic acid and ciprofloxacin were determined in 7 nalidixic acid-resistant strains by the E test (AB Biodisk Dalvagen, Solma, Sweden). The results of these tests are shown in Tables 1 and 2. GyrA, GyrB, ParC, and ParE point mutations in these isolates were genetically characterized (11). The results showed amino acid amino acid (əmē`nō), any one of a class of simple organic compounds containing carbon, hydrogen, oxygen, nitrogen, and in certain cases sulfur. These compounds are the building blocks of proteins. substitutions only in GyrA: Ser83 [right arrow] Phe or Tyr and Asp87 [right arrow] Asn or His (GenBank accession no. AY858891) (Tables 1 and 2). To define clusters, PFGE was carried out according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. the Salm-gene protocol (12) by using the CHEF-DR II System (Bio-Rad Laboratories, Hercules, CA, USA). Fingerprints were compared with GelCompar (Applied Maths, Kortrijk, Belgium). Pattern clustering was performed by using the unweighted pair group method with an arithmetic mean (mathematics) arithmetic mean - The mean of a list of N numbers calculated by dividing their sum by N. The arithmetic mean is appropriate for sets of numbers that are added together or that form an arithmetic series. and the Dice coefficient (13) with a tolerance of 0.8%. Each PFGE profile or clone, which differed by at least 1 band from a previously recognized type, was considered a distinct profile. Twenty-four PFGE profiles were observed among the 110 strains (Figure 1). A total of 10, 9, 2, 4, and 6 clones were detected in strains from human, food, environmental, sick animal, and slaughtered swine sources, respectively (Tables 1 and 2). Twelve clones displayed closely related profiles, and paired PFGE profiles differed from each other by 1 band (1-2, 2-3, 4-5, 9-10, 12-13, and 12-14), 2 bands (1-3 and 13-14), or 3 bands (16-18) (Figure 2). [FIGURE 2 OMITTED] Eleven PFGE profiles (10.0% of the strains) were unique. Conversely, PFGE profile 1 accounted for 52.7% of all isolates studied: 3 from humans, 12 from food, l from the environment, 1 from an ill swine, and 42 from 30 slaughtered swine (Tables 1 and 2). PFGE profile 8 represented 10.0% of the characterized strains isolated from 11 swine slaughtered at operation B finishing unit B3. No other PFGE profile accounted for >3% of the strains. In the 63 strains obtained from 48 swine slaughtered, 6 PFGE profiles were observed: 1 (62.5%), 2 (4.2%), 8 (22.9%), 15 (4.2%), 21 (2.8%), and 22 (4.2%). The corresponding values of genetic similarity ranged from 32% to 96% according to the dendrogram A dendrogram is a tree diagram frequently used to illustrate the arrangement of the clusters produced by a clustering algorithm (see cluster analysis). Dendrograms are often used in computational biology to illustrate the clustering of genes. constructed with the different PFGE profiles (Figure 2). Typeability was [approximately equal to] 96.3% because autodigestion occurred in 4 strains. The discriminatory ability calculated by using the Simpson index Simpson's diversity index (also known as Species diversity index) is a measure of diversity. In ecology, it is often used to quantify the biodiversity of a habitat. It takes into account the number of species present, as well as the relative abundance of each species. was 0.9931 for the LNRSSE group, which was selected without a geographic link for any isolates. Conclusions The study was conducted because of the S. Derby isolate, detected through Salmonella surveillance programs, emerged on several swine farms in Spain. We investigated the genetic diversity of S. Derby isolates in these herds by using PFGE to obtain information on their genetic backgrounds. The predominant clone (clone 1) was identified in 42 strains isolated from 30 animals at 4 swine operations and 5 finishing units. It appeared as a single clone in 3 swine operation finishing units (A-1, A-2, and C-4), or in combination with other PFGE profiles (8 for B-3; 2 and 21 for D-5). When the persistence of a clone was detected, we tracked its spread from food products to humans by testing S. Derby strains isolated from humans, food, the environment, and ill animals in different areas of Spain. Clone 1 was identified in 18.7% of human strains, 52.2% of food strains, as well as in a strain collected on a beach and in another from an ill animal. Moreover, a closely related clone (clone 2) was detected with clone 1 in the swine operation finishing unit D4. This finding might be the result of these clones sharing a common ancestor. The dissemination of clone 1 may be more widespread because LNRSSE group isolates were selected on the basis of no epidemiologic links and were not associated with national or local food outbreaks. Because resistance of Salmonella to antimicrobial agents is a worldwide problem, drug susceptibility was also examined. Resistance to amoxicillin-clavulanate, cephalosporins Cephalosporins Definition Cephalosporins are medicines that kill bacteria or prevent their growth. Purpose Cephalosporins are used to treat infections in different parts of the body—the ears, nose, throat, lungs, sinuses, and , imipenem, and fluoroquinolones was not detected. However, resistance to tetracycline was high ([approximately equal to] 75%), which is similar to that recorded in a study of 304 S. Derby swine isolates (9), but differs from that obtained in human and food isolates (49%) (14). In addition, susceptible isolates from the swine group showed increased resistance to other drugs when compared with those in the LNRSSE group. No relationship was observed between the time of isolation of a specific clone and increased resistance. A novel GyrA mutation (Hys 87) was identified in 4 swine strains of clone 1 that showed resistance to nalidixic acid and low-level resistance to ciprofloxacin. These strains, which also showed resistance to other antimicrobial agents (ampicillin, streptomycin, gentamicin gentamicin /gen·ta·mi·cin/ (jen?tah-mi´sin) an aminoglycoside antibiotic complex isolated from bacteria of the genus Micromonospora, , tobramycin tobramycin /to·bra·my·cin/ (to?brah-mi´sin) an aminoglycoside antibiotic derived from a complex produced by Streptomyces tenebrarius, , netilmicin, tetracycline, and sulfamethoxazole sulfamethoxazole /sul·fa·meth·ox·a·zole/ (-meth-ok´sah-zol) a sulfonamideantibacterial and antiprotozoal, particularly used in acute urinary tract infections. sul·fa·me·thox·a·zole n. ), may be attributed to multiple resistance factors present on transmissible transmissible /trans·mis·si·ble/ (trans-mis´i-b'l) capable of being transmitted. trans·mis·si·ble adj. Capable of being conveyed from one person to another. genetic elements (15). In summary, this study detected a clone of S. Derby in pork-derived products and subsequently in humans. Our results emphasize the need for safe food-handling practices to limit the intake of raw or undercooked pork, and procedures to avoid colonization of swine herds with Salmonella. They also support establishing guidelines to reduce foodborne pathogens on swine farms and in slaughterhouses. Moreover, because of the emergence of bacterial resistance to antimicrobial agents as a result of their extensive use in animal husbandry, measures such as modification of doses of antimicrobial agents, control of Salmonella infections in primary production facilities, and effective epidemiologic surveillance epidemiologic surveillance The ongoing, systematic collection, analysis, and interpretation of health data essential to planning, implementing, and evaluating public health practice, closely integrated with the timely dissemination of these data to those who need to know must be implemented to determine potential routes and spread of infection.
Table 1. Characteristics of Salmonella enterica Derby serotype isolates
(N = 47) from the LNRSSE Group (Spanish National Reference Laboratory
for Salmonella and Shigella) *
Isolation Geographic PFGE
Specimen date origin profile
Human origin
(16 strains)
1 9/4/01 Barcelona 19
2 3/5/02 Lugo 4
3 4/25/02 Madrid 3
4 4/25/02 Unknown NT
5 5/23/02 Orense 10
6 7/27/02 Castellon 17
7 7/27/02 Barcelona 11
8 7/8/02 Zaragoza 11
9 8/8/02 Barcelona 1
10 8/20/02 Tarragona 23
11 8/22/02 Alicante 16
12 7/8/02 Oviedo 1
13 9/1/02 Zamora 1
14 9/30/02 Huesca 16
15 11/28/02 Ciudad Real 23
16 11/5/02 Caceres 5
Food origin
(23 strains)
Unknown 3/22/02 Barcelona 18
Seafood 5/1/00 Salamanca 14
Sausage 5/2/00 Bilbao 1
Pork 6/11/00 Cadiz 7
Pork 6/16/00 Granada 23
Pork 7/10/00 Zaragoza 1
Sausage 6/16/00 Navarra 1
Lamb 1/10/01 Malaga 1
Minced meat 4/2/01 Toledo 12
Unknown 7/4/01 Valencia 12
Sausage 7/2/01 Granada 1
Minced meat 10/5/00 Toledo 13
Unknown 7/18/00 Vitoria NT
Corn 12/31/01 Bilbao NT
Hamburger 4/16/02 Cordoba 1
Pork 4/19/02 Jaen 1
Sausage 5/28/02 Soria 1
Pork 6/14/02 Oviedo 1
Pork 6/19/02 Oviedo 1
Pork 9/10/02 Madrid 1
Unknown 9/26/02 Burgos 1
Sausage 10/29/02 Barcelona 24
Pork 9/1/02 Lugo 20
Environmental origin
(2 strains)
Groundwater 9/3/01 Valencia 12
Beach 2/29/02 Bilbao 1
III animal origin
(6 strains)
-- -- Soria 14
Swine 5/22/02 Toledo 1
Swine 3/7/02 Leon 6
Swine 3/7/02 Leon 6
Swine 3/6/02 Leon 6
Swine 1/22/02 Leon 9
GyrA mutation
Specimen Resistance profile ([dagger])
Human origin
(16 strains)
1
2 T
3 S,Su
4 A,S,Su,T,C,Nx Tyr 83 (>256/0.12)
5 A,S,Su,T,C
6
7 A,S,G,To,Ap,Su,T,SxT
8
9 Su,T,SxT
10
11 S,T,Nx Asn 87 (64/0.09)
12 S,Su,T
13 S,Su,T
14 T
15 S,Su,T
16 A,T
Food origin
(23 strains)
Unknown S,Su,T,SxT
Seafood A,Su,T,SxT
Sausage Su,T
Pork T
Pork Nx Phe 83 (>256/0.09)
Pork S,Su,T
Sausage S,Su,T
Lamb A,T
Minced meat S,T
Unknown S,T
Sausage S,Su,T
Minced meat T
Unknown A
Corn
Hamburger Nx Phe 83 (>256/0.1)
Pork S,Su,T
Sausage S,Su,T
Pork S,Su,T
Pork S,Su,T
Pork T
Unknown Su,T,SxT
Sausage T
Pork T
Environmental origin
(2 strains)
Groundwater S,T
Beach Su,T,SxT
III animal origin
(6 strains)
-- A,T
Swine S,SuT
Swine S,T
Swine S,T
Swine S,T
Swine Su,T,SxT
* PFGE, pulsed-field gel electrophoresis; Nx, nalidixic acid; Cp,
ciprofloxacin; T, tetracycline; S, streptomycin; Su, sulfamethoxazole;
NT, not typeable; A, ampicillin; C, chloramphenicol; G, gentamicin; To,
tobramycin; Ap, apramycin; SxT, cotrimoxazole.
([dagger]) MIC for Nx/Cp, [micro]g/mL.
Table 2. Salmonella enterica * Derby strains (N = 63) from the swine
group
No. of No. of
PFGE PFGE
profiles/ profiles
Swine operations/ resistance (no. of Resistance phenotype
finishing units patterns swine) (no. of swine)
A-1 (6 strains) 1/2 1 (5) S,G,To,Su,T,C (1)
A,S,G,To,Nt,Su,T,Nx,C (4)
([dagger])
A-2 (3 strains) 1/1 1 (3) A,S,G,Su,T,C (3)
B-3 (16 strains) 2/7 1 (4) (1) ([double dagger])
S,Su,T (2)
S,Su,T,C (1)
8 (11) (1) ([section])
(1) ([double dagger])
S,Su,T (8)
A,S,G,To (1)
C-4 (1 strain) 1/1 1 (1) S,Su,T (1)
D-5 (32 strains) 3/3 1 (17) S,Su,T (17)
2 (2) S,Su,T (2)
21 (1) A,S,Su,T,SxT (1)
D-6 (5 strains) 2/4 22 (2) A,S,G,T,Ap,Su,SxT,C (1)
A,S,G,To,Ak,Su,T,SxT,C (1)
15 (2) T (1)
A,S,G,To,T (1)
* Identified in 48 swine slaughtered at 4 swine operations (A-D) and 6
finishing units (1-6) in Spain. PFGE, pulsed-field gel electrophoresis;
S, streptomycin; G, gentamicin; To, tobramycin; Su, sulfamethoxazole;
T, tetracycline; C, chloramphenicol, A, ampicillin; Nt, netilmicin;
SxT, cotrimoxazole.
([dagger]) GyrA mutation (MIC nalidixic acid/ciprofloxacin): Hys 87 =
48/0.09Ug/mL.
([double dagger]) Susceptible to all antimicrobial agents tested except
spectinomycin.
([section]) Susceptible to spectinomycin.
Acknowledgments We thank the laboratories in Spain for sending strains to LNRSSE. This work was supported by a grant from the Ministerio de Ciencia y Tecnologia (AGL (programming) AGL - (Atelier de Genie Logiciel) French for IPSE. 2002-04161-02-01). Sylvia Valdezate and Ana Vidal were supported by fellowships from Instituto de Salud Carlos III Carlos III may refer to:
Use of trade names is for identification only and does not imply endorsement by the Public Health Service or by the U.S. Department of Health and Human Services Noun 1. Department of Health and Human Services - the United States federal department that administers all federal programs dealing with health and welfare; created in 1979 Health and Human Services, HHS . References (1.) Gomez TM, Motarjemi Y, Miyagawa S, Kaferstein FK, Stohr K. Foodborne salmonellosis. World Health Stat Q. 1997;50:81-9. (2.) Berends BR, van Knapen F, Mossel DA, Burr SA. Snijders JM. Identification and quantification of risk factors regarding Salmonella spp. on pork carcasses. Int J Food Microbiol. 1997:36:199-206. (3.) Korsak N, Daube For other uses of "Daub(e)", see Daub. Daube is a classic French stew made with cubed beef braised in wine, vegetables, garlic, and herbes de provence. Although most modern recipes call for red wine, a minority call for white wine, and the earliest recorded daube recipes call G, Ghafir Y, Chahed A, Jolly S, Vindevogel H. An efficient sampling technique used to detect 4 foodborne pathogens on pork and beef carcasses in nine Belgian abattoirs. J Food Prot. 1998;61:535-41. (4.) Mogstad LL. Salmonella spp. in the stomach contents of slaughtered pigs. A possible factor of contamination in the plucks and fresh meat. Dansk Veterinaenidskrift. 1995:78:554-7. (5.) Centers for Disease Control and Prevention. Salmonella surveillance summary 2002. Atlanta: 2003. (6.) Giovannacci I. Oueguiner S, Ragimbeau C, Sahat G, Vendeuvre JL. Carlier V, et al. Tracing of Salmonella spp. in 2 pork slaughter and cutting plants using serotyping and macrorestriction genotyping. J Appl Microbiol. 2001:90:131-47. (7.) Watabe M. Rao JR. Stewart TA, Xu J. Millar BC. Xia L, et al. Prevalence of bacterial faecal fae·cal adj. Chiefly British Variant of fecal. Adj. 1. faecal - of or relating to feces; "fecal matter" fecal pathogens in separated and unseparated stored pig slurry. Left Appl Microbiol. 2003;36:208-12. (8.) Maguire HC, Codd AA, Mackay VE, Rowe B. Mitchell E. Outbreak of human salmonellosis traced to a local pig Farm. Epidemiol Infect. 1993;110:239-46. (9.) Grebeyenes WA. Davies PR, Morrow WE, Funk JA. Altier C. Antimicrobial resistance of Salmonella isolates from swine. J Clin Microbiol. 2000:38:4633-6. (10.) Letellier A, Messier S, Pare J, Menard J, Quessy S. Distribution of Salmonella in swine herds in Quebec. Vet Microbiol. 1999;67:299-306. (11.) Giraud E, Brisabois A, Marlel JL, Chaslus-Dancla E. Comparative studies of mutations in animal isolates and experimental in vitro- and in vivo-selected mutants of Salmonella spp. suggest a counterselection of highly fluoroquinolone-resistant strains in the field. Antimicrob Agents Chemother. 1999:43:2131-7. (12.) Peters TM, Maguire C, Threlfall EJ, Fisher IST. Guill N. Gatto AJ. The Salm-gene project--a European collaboration for DNA fingerprinting DNA fingerprinting or DNA profiling, any of several similar techniques for analyzing and comparing DNA from separate sources, used especially in law enforcement to identify suspects from hair, blood, semen, or other biological materials found at for food-related salmonellosis. Eurosurveillance. 2003:8:46-50. (13.) Nei M, Li WH. Mathematical model for subtyping genetic variation in terms of restriction endonucleases. Proc Natl Acad Sci U S A. 1979:76:5269-73. (14.) Ling JM, Chan EW, Lam AW, Cheng AF. Mutations in topoisomcrase genes of fluoroquinolone-resistant salmonellae in Hong Kong. Antimicrob Agents Chemother. 2003:47:3567-73. (15.) Piddock LJ. Fluoroquinolone fluoroquinolone /flu·o·ro·quin·o·lone/ (-kwin´o-lon) any of a subgroup of fluorine-substituted quinolones, having a broader spectrum of activity than nalidixic acid. fluor·o·quin·o·lone n. resistance in Salmonella serovars isolated from humans and food animals. FEMS FEMS Federation of European Microbiological Societies FEMS Federation of European Materials Societies FEMS Fabrication Engineering Management System FEMS Facility Equipment Maintenance System (PMEL/TMDE) Microbiol Rev. 2002:26:3-16. Sylvia Valdezate, * Ana Vidal, ([dagger]) Silvia Herrera-Leon, * Javier Pozo, ([dagger]) Pedro Rubio, ([dagger]) Miguel A. Usera, * Ana Carvajal, ([dagger]) and M. Aurora Echeita * * Instituto de Salud Carlos III, Madrid, Spain; and ([dagger]) Universidad de Leon, Leon, Spain Address for correspondence: Sylvia Valdezate. Servicio de Bacteriologia C.N.M., Instituto de Salud Carlos III. Majadahonda, Crra. Majadahonda-Pozuelo Km 2, Madrid 28220, Spain: fax: 34-91-509-7966: email: svaldezate@isciii.es Dr. Valdezate is a microbiologist in the bacteriology bacteriology Study of bacteria. Modern understanding of bacterial forms dates from Ferdinand Cohn's classifications. Other researchers, such as Louis Pasteur, established the connection between bacteria and fermentation and disease. department at the Instituto de Salud Carlos Ill in Majadahonda, Spain. Her research focuses on the transmission and dynamics of nosocomial nosocomial /noso·co·mi·al/ (nos?o-ko´me-il) pertaining to or originating in a hospital. nos·o·co·mi·al adj. 1. Of or relating to a hospital. 2. and foodborne infectious diseases by using molecular typing methods. |
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