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Letter
Resistant Salmonella
Virchow in Quail Products
Frank M. Aarestrup,*
Henrik Hasman,* and Lars Bogø Jensen*
*Danish Institute for Food and Veterinary Research, Copenhagen V, Denmark
Suggested
citation for this article
To the Editor: Salmonella spp. resistant to multiple antimicrobial
agents have emerged worldwide in recent years, but clinical relevance
varies with the agent to which resistance evolves. Fluoroquinolones are
often the drug of choice to treat gastrointestinal infections in humans,
and resistance to this class of antimicrobial agents is associated with
increased illness and death (1). Resistance to fluoroquinolones
has emerged worldwide during the last decade. Salmonella isolates
resistant to oxyiminocephalosporins because they produce extended-spectrum
β-lactamases (ESBLs) have emerged worldwide since 1992. This emergence
has caused concern since cephalosporins are drugs of choice to treat salmonellosis
in children, to whom fluoroquinolones must not be administered because
of toxicity issues. In Denmark, the first ESBL-producing isolate of animal
origin from a Salmonella enterica serovar Heidelberg isolated from
a boar imported from Canada in 2003 was reported (2),
but such isolates have not previously been reported in food products.
On October 15, 2003, the Danish Institute for Veterinary Research, the
national reference laboratory, received 3 Salmonella isolates found
in quails imported from France. Salmonella isolates found at any
importer's laboratory in Denmark are submitted to the reference laboratory
for further analyses. The quails were in the importer's storage room at
the time of sampling; sampling was performed routinely by the importer's
own laboratory. At the reference laboratory, the isolates were serotyped
as S. enterica serovar Virchow and found resistant to ampicillin,
ceftiofur, cephalothin, nalidixic acid, and tetracycline and with reduced
susceptibility to ciprofloxacin (MICs >0.125 μg/mL) (3).
Polymerase chain reaction detection and sequencing (4)
showed that the β-lactam resistance was mediated by blaCTX-M-9.
Pulsed-field gel electrophoresis was performed by using XbaI and
BlnI as restriction enzymes according to the PulseNet protocol
(5), and all 3 isolates had the same profile.
On October 23, the importer was informed of the laboratory's findings
and the increased risk associated with salmonella isolates simultaneously
resistant to quinolones and cephalosporins. Based on this information,
the importer withdrew the product from the supermarkets on October 24.
Recently, S. enterica Virchow with blaCTX-M-9
has also been reported in poultry, poultry products, and humans in France
(6), as well as humans in Spain (7)
and the United Kingdom (8). The isolates from France
were also resistant to nalidixic acid; the isolates we have obtained from
fresh quails imported from France are possibly related to these isolates.
The global food-products trade is expected to increase in the future.
Thus, attempts to improve food safety must emphasize detection of antimicrobial
drug–resistant bacteria in imported food products. Furthermore, international
agreements that limit contamination with drug-resistant bacteria and resistance
genes at the primary production site are necessary to ensure consumer
safety (9). International agreements must be based on
antimicrobial-resistance data and early reports of emerging problems.
Recently, the World Health Organization (WHO) launched the Global Salm
Surv program (10) to isolate and identify antimicrobial
resistance to Salmonella globally.
Many national and international rules, as well as marketing and consumer
factors, regulate the international trade of food products and live animals.
Large international corporations may also affect international trade.
For example, McDonald's Corporation has issued a global policy for antimicrobial
drug use in food animals that specifies requirements for their food product
suppliers. Local groceries or supermarkets may also impose their own standards
nationally. We are aware of only 1 product withdrawal related to antimicrobial
resistance, the quail imported from France.
No international standards exist for managing food safety problems related
to antimicrobial resistance. However, in 2003 the Food and Agriculture
Organization of the United Nations, WHO, and the World Organisation for
Animal Health jointly hosted a workshop with a panel of experts to scientifically
assess resistance risks related to nonhuman use of antimicrobial drugs
(9). The panel's purpose was also to provide recommendations
to the Codex Alimentarius Commission for future risk management of antimicrobial
drug resistance (9). Imposing restrictions on products
with combinations of resistance, such as simultaneous resistance to quinolones
and cephalosporins in Salmonella, as reported in this study, would
be a good first step towards managing antimicrobial drug–resistance risks.
References
- Helms M, Simonsen J, Mølbak K. Quinolone
resistance is associated with increased risk of invasive illness or
death during infection with Salmonella serotype Typhimurium.
J Infect Dis. 2004;190:1652–4.
- Aarestrup FM, Hasman H, Olsen I, Sørensen G. International
spread of bla(CMY-2)-mediated cephalosporin resistance in a multiresistant
Salmonella enterica serovar Heidelberg isolate stemming from
the importation of a boar by Denmark from Canada. Antimicrob Agents
Chemother. 2004;48:1916–7.
- Aarestrup FM, Lertworapreecha M, Evans MC, Bangtrakulnonth A, Chalermchaikit
T, Hendriksen RS, et al. Antimicrobial
susceptibility and occurrence of resistance genes among Salmonella
enterica serovar Weltevreden from different countries. J Antimicrob
Chemother. 2003;52:715–8.
- Hasman H, Mevius D, Veldman K, Olesen I, Aarestrup FM. β-Lactamases
among extended-spectrum beta-lactamase (ESBL) resistant Salmonella
from poultry, poultry products and human patients in The Netherlands.
J Antimicrob Chemother. 2005;56:115–21.
- Ribot EM, Wierzba RZ, Angulo FJ, Barrett TJ. Salmonella
enterica serotype Typhimurium DT104 isolated from humans, United
States, 1985, 1990, and 1995. Emerg Infect Dis. 2002;8:387–91.
- Simarro E, Navarro F, Ruiz J, Miro E, Gomez J, Mirelis B. Salmonella
enterica serovar Virchow with CTX-M-like beta-lactamase in Spain.
J Clin Microbiol. 2000;38:4676–8.
- Weill FX, Lailler R, Praud K, Kerouanton A, Fabre L, Brisabois A,
et al. Emergence
of extended-spectrum-beta-lactamase (CTX-M-9)-producing multiresistant
strains of Salmonella enterica serotype Virchow in poultry and
humans in France. J Clin Microbiol. 2004;42:5767–73.
- Batchelor M, Hopkins K, Threlfall EJ, Clifton-Hadley FA, Stallwood
AD, Davies RH, et al. bla(CTX-M)
genes in clinical Salmonella isolates recovered from humans in
England and Wales from 1992 to 2003. Antimicrob Agents Chemother.
2005;49:1319–22.
- World Health Organization. Geneva: 1st Joint FAO/OIE/WHO expert workshop
on non-human antimicrobial usage and antimicrobial resistance: scientific
assessment. Geneva: The Organization; 2003 [cited 1 Mar 2005]. Available
from http://www.who.int/foodsafety/publications/micro/en/amr.pdf
- World Health Organization. Global Salm Surv (GSS). Geneva: The Organization;
2004 [cited 1 Mar 2005]. Available from http://www.who.int/salmsurv/en/
Suggested citation
for this article:
Aarestrup FM, Hasman
H, Jensen LB. Resistant Salmonella Virchow in quail products [letter].
Emerg Infect Dis [serial on the Internet]. 2005 Dec [date cited].
Available from http://www.cdc.gov/ncidod/EID/vol11no12/05-0977.htm
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