Jürgen Wallmann

In the European Union, various fluoroquinolones are authorised for the treatment of food producing animals. Each administration poses an increased risk of development and spread of antimicrobial resistance. The aim of this study was to investigate the impact of parenteral administration of enrofloxacin on the prevalence of enrofloxacin and ciprofloxacin susceptibilities in the commensal intestinal E. coli population. E. coli isolates from faeces of twelve healthy pigs were included. Six pigs were administered enrofloxacin on day 1 to 3 and after two weeks for further three days. The other pigs formed the control group. MIC values were determined. Virulence and resistance genes were detected by PCR. Phylogenetic grouping was performed by PCR. Enrofloxacin and ciprofloxacin were analysed in sedimentation samples by HPLC. Susceptibility shifts in commensal E. coli isolates were determined in both groups. Non-wildtype E. coli could be cultivated from two animals of the experimental group for the first time one week after the first administration and from one animal of the control group on day 28. The environmental load with enrofloxacin in sedimentation samples showed the highest amount between days one and five. The repeated parenteral administration of enrofloxacin to pigs resulted in rapidly increased MIC values (day 28: MIC up to 4 mg/L, day 35: MIC ≥ 32mg/L). E. coli populations of the control group in the same stable without direct contact to the experimental group were affected. The parenteral administration of enrofloxacin to piglets considerably reduced the number of the susceptible intestinal E. coli population which was replaced by E. coli strains with increased MIC values against enrofloxacin. Subsequently also pigs of the control were affected suggesting a transferability of strains from the experimental group through the environment to the control group especially as we could isolate the same PFGE strains from both pig groups and the environment.

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For the implementation of risk management measures against the development and spread of antimicrobial resistances it is important to gain a quantitative insight into the use of veterinary antimicrobial agents. Since 2011, all pharmaceutical companies and wholesalers in Germany are required to report their sales data of veterinary antimicrobial products (VAPs). In 2011, 1706 t of antimicrobially active substances were sold to veterinarians registered in Germany, in 2012 the amount decreased to 1619 t. Tetracyclines and penicillins had the largest shares in both years, followed by sulfonamides, macrolides and polypeptides. Amoxicillin alone accounted for more than a quarter of the total amounts of all sold antimicrobials. In regard to AMR it is most important to limit the use of critically important antimicrobials, namely fluoroquinolones and 3rd and 4th generation cephalosporins. While in both years these groups accounted for less than 1% of the amount of sold antimicrobials, this does not reflect adequately their use, since they are used in much lower doses. Furthermore, it is worrying that the sales of fluoroquinolones and 3rd generation cephalosporins increased by 26% and 14%, respectively, between 2011 and 2012, while the sales of 4th generation cephalosporins decreased only by 2%. More than 95% of the active substances were contained in VAPs intended for oral application; only fluoroquinolones, 3rd and 4th generation cephalosporins as well as fenicols were primarily or even exclusively applied by injection.

GERMAP ist konzipiert als Bericht und Atlas zum Antibiotikaverbrauch und zur Antibiotikaresistenz in der Human- und Veterinärmedizin. Der Bericht wird gemeinsam vom Bundesamt für Verbraucherschutz und Lebensmittelsicherheit, der Paul-Ehrlich-Gesellschaft für Chemotherapie und dem Infektionszentrum am Universitätsklinikum Freiburg in Zusammenarbeit mit 11 weiteren Gesellschaften, Verbänden, Institutionen herausgegeben. Bisher erschienen GERMAP 2008 und GERMAP 2010. GERMAP ist kostenlos im Internet als pdf-Datei erhältlich. Vorbilder für GERMAP sind die seit vielen Jahren in skandinavischen Ländern verfügbaren ähnlichen Berichte. GERMAP 2010 zeigt die bis 2008 /2009 aktualisierten verfügbaren Daten zum Antibiotikaverbrauch in der Humanmedizin, enthält gegenüber GERMAP 2008 leider keine aktualisierten Daten zum Antibiotikaverbrauch in der Veterinärmedizin, zu denen aufgrund einer neuen Verordnung zur Erfassung der Abgabemengen in GERMAP 2012 vermutlich wieder berichtet werden kann. Zu wichtigen Befunden im Bereich Antibiotikaresistenz in der Humanmedizin gehört die Beobachtung, dass MRSA-Stämme relativ gut empfindlich gegenüber Cotrimoxazol, Doxycyclin, Rifampicin, Linezolid und Gentamicin waren. Clindamycin-Resistenz war bei den klassischen nosokomialem MRSA hoch ( > 50 %), bei den ambulant erworbenen MRSA niedrig ( < 10 %). Die Daten zur Penicillin-Resistenz von Pneumokokken, den häufigsten Erregern ambulant erworbener Pneumonien im Erwachsenenalter, zeigen eine konsistent sehr niedrige Rate für Deutschland. Für die Fluorchinolon-Resistenz von E. coli schwankten die Werte zwischen < 10 % und > 20 %. Relativ hohe Resistenzraten zeigen die Isolate von verschiedenen Tieren und unterschiedlichen Indikationen bei Ampicillin, Tetracyclinen und Cotrimoxazol. Die Fluorchinolon-Resistenzrate bei E.coli vom Tier war sehr unterschiedlich; bei Isolaten von Kälbern betrug sie > 25 %, bei Isolaten von Ferkeln, Masthähnen und Truthühnern < 10 %. GERMAP 2012 ist bereits in Arbeit und wird zu vielen Kapiteln neue Daten präsentieren können. Zunehmend sollen Kommentare, spezielle Berichte und Stellungnahmen integriert werden. Es soll damit eine bessere Basis für die Entwicklung von Leitlinien und Empfehlungen für die adäquate Therapie von Infektionskrankheiten bei Menschen und Tieren wie auch für politische Meinungsbildung und Entscheidungshilfe geschaffen werden.

To determine the current status of antimicrobial susceptibility of bacterial pathogens from animals in Germany, the Bff-GermVet monitoring program was initiated as a complementary program to the German national monitoring program GERM-Vet conducted by the Federal Office of Consumer Protection and Food Safety (BVL). In the Bff-GermVet program, a total of 1,626 bacterial strains, obtained during a 27-month period (01/2004-03/2006) from 31 indications, was screened for susceptibility against 22 antimicrobial agents and two combinations of antimicrobial agents. Selected bacteria were additionally tested for their susceptibility against additional three combinations of antimicrobial agents and the corresponding single substances. This paper describes the overall aims and the structure of the program with particular reference to the sampling strategy, the methodology for susceptibility testing and the interpretive criteria used for evaluation of the results.

A total of 368 bacterial pathogens, including 72 coagulase-positive and coagulase-variable staphylococci, 97 beta-haemolytic streptococci, 51 Escherichia coli, 75 Pasteurella multocida, 25 Mannheimia haemolytica, 25 Pseudomonas aeruginosa, and 23 Arcanobacterium pyogenes, were investigated for their susceptibility to the three combinations of antimicrobial agents lincomycin/spectinomycin (1/2), penicillin G/neomycin (1/1), and penicillin G/dihydrostreptomycin (1/1) in comparison to their susceptibility to the corresponding single substances. When comparing the minimum inhibitory concentrations (MICs) determined for any of the three combinations with those for the single substances, the lowest MIC of one of the two substances usually determined the MIC of the combination.This observation was made for all three combinations and all bacterial pathogens tested.Thus, it is assumed that the combination of lincomycin with spectinomycin as well as that of penicillin with either neomycin or dihydrostreptomycin resulted in an extended spectrum of target bacterial pathogens rather than in an increase in antimicrobial efficacy.

A total of 248 coagulase-positive and coagulase-variable staphylococci from two indications of swine (infections of the urinary/genital tract including strains from the mastitis metritis agalactia syndrome as well as infections of the skin) as well as two indications of dogs/cats (respiratory tract infections and infections of skin/ear/mouth) were investigated for their susceptibility to numerous antimicrobial agents. Regardless of the animal origin and indication, the most frequently detected resistance properties were resistances against penicillin G (53-77%) and ampicillin (42-75%), tetracycline (33-52%) as well as erythromycin (13-27%). Oxacillin-resistant staphylococci were rarely detected.