What are the public health issues that practitioners have to consider to enforce a sustainable use of antibiotics P.L. Toutain National Veterinary School ; Toulouse, France Noordwijkerhout July NL

The priorities of a sustainable veterinary antibiotherapy is related to public health issues, not to animal health issues

Medical consequences of antimicrobial resistance

The antibiotic ecosystem: one world, one health Treatment & prophylaxis Human medicine Community Veterinary medicine Animal feed additives Environment Hospital Agriculture Plant protection Industry

But of what resistance are we speaking?

Prevent emergence of resistance: but of what resistance?

7 The 4 human risks associated to the use of antibiotics in veterinary medicine to minimize 1.Decrease in susceptibility or full resistance of zoonotic pathogens passing from animal to man either directly or throughout the food chain 2.Development of resistance in commensal flora and passage of resistance gene throughout the food chain or the environment 3.Release of antibiotics in the environment with different consequences including emergence of resistance (gene, pathogens) 4.Antibiotic residues in food

Q1-For AR, what are the critical veterinary ecosystems in terms of public health (commensals)

The critical animal ecosystems in terms of emergence and spreading of resistance Open and large ecosystems –Digestive tract –Skin Open but small ecosystem –Respiratory tract Closed and small ecosystem –Mammary gland

Bacterial load exposed to antibiotics during a treatment Infected Lungs Digestive tract 1 mg2-3Kg Manure Sludge waste Food chain Several tons Soil, plant…. 1µg Test tube

Biophases & antimicrobial resistance G.I.T Proximal Distal Résistance = lack of efficacy Blood Gut flora Zoonotic (salmonella, campylobacter commensal ( enterococcus) 1-F% F% Target biophase Bug of vet interest AB: oral route Résistance = public health concern Food chain Environmental exposure

12 Biodisponibilité orale des tétracyclines chez le porc Chlortétracycline: –Pigs Fasted or fed: 18 to 19% Doxycycline: –Pigs :23% Oxytétracycline: –Pigs:4.8% –Piglets, weaned, 10 weeks of age: by drench: 9%;in medicated feed for 3 days: 3.7%. Tétracycline: –Pigs fasted:23%. La majeure partie des doses administrées de tétracyclines n’est pas utile pour l’animal mais expose inutilement ses flores digestives et l’environnement

Biophases & antibiorésistance Gastrointestinal tract Proximal Distal Intestinal secretion Bile Résistance = lack of efficacy Résistance =public health issue Biophase Target pathogen Blood Food chain Environment Systemic Administration Quinolones Macrolides Tétracyclines Gut flora Zoonotic (salmonella, campylobacter commensal ( enterococcus)

14 Marbofloxacin impact on E. coli in pig intestinal flora (From P. sanders, Anses, Fougères) Before treatment : E. coli R (0.01 to 0.1%) After IV. :Decrease of total E coli, slight increase of E. coli R (4 to 8 %) Back to initial level After repeated IM (3d) : Decrease below LoD E. coli (2 days), fast growth (~ ufc/g 1 d). E. coli R followed to a slow decrease back to initial level after 12 days IV IM 3 days

Iqpaïa Influence d’une administration d’amoxicilline sur la flore digestive du porc (excrétion du gène bla TEM )

Performance-enhancing antibiotics (old antibiotics) – chlortetracycline, sulfamethazine, and penicillin (known as ASP250)] phylogenetic, metagenomic, and quantitative PCR-based approaches to address the impact of antibiotics on the swine gut microbiota

It was shown that antibiotic resistance genes increased in abundance and diversity in the medicated swine microbiome despite a high background of resistance genes in nonmedicated swine. Some enriched genes, demonstrated the potential for indirect selection of resistance to classes of antibiotics not fed.

Daily bacterial shedding for a grower pigs E coli: 7.5 g per days Enterococcus: about 300 µg per days =7.5x10 6 A 20- to 100-fold greater E. coli abundance in medicated than nonmedicated swine

- 19 Innovation: PK selectivity of antibiotics environment Proximal Distal Blood Gut flora Zoonotic (salmonella, campylobacter commensal ( enterococcus) Biophase Résistance = public health concern Food chain 1-F=90% F=10% Animal health Efflux Quinolones, macrolides IM Kidney Oral

Q2-What is the actual veterinary contribution to the human AR

What is the actual veterinary contribution to the human AR 1.A direct contribution to resistance for zoonotic pathogens (Salmonella, Campylobacter…) 2.A possible transmission of commensal bacteria that may transmit resistance determinants to human pathogens 3.An indirect contribution for MRSA (pets as carriers and reservoirs)

Trends and Sources of Zoonosis in EU EFSA/ECDC

Reported zoonoses in UE, VTEC: E Coli verotoxinogène Within Y. enterocolitica, the majority of isolates from food and environmental sources are non-pathogenic types.

Deaths due to salmonellosis, campylobacteriosis & E coli (report2010) Based on the reported fatality rates and the total numbers of reported confirmed cases, it is estimated that there were approximately 130 deaths due to salmonellosis, 212 due to campylobacteriosis and 16 due to E coli in EU. 24

Treatments of salmonellosis & campylobacteriosis Usually no antibiotics Only to treat sever cases in a risky patients 25

Antibiotics used to treat salmonellosis & campylobacteriosis Salmonella –Fluoroquinolones –Cephalosporins (third generation) –No quinolones for children Campylobacter – Macrolides –Fluoroquinolones

Antibiotics used to treat Verotoxigenic E coli The use of antimicrobials for the treatment of human infections with VTEC is controversial. In general, antimicrobials are not recommended as their usage may exacerbate symptoms, particularly haemolytic uraemic syndrome. 27

28 Treatments of zoonotic pathogens in man : is there some AR?

Salmonella & campylobacter : AR in human in US

Percentage of non-typhoidal Salmonella isolates resistant to nalidixic acid, by year, 1996–2010

Percentage of non-typhoidal Salmonella isolates resistant to ceftriaxone, by year, 1996–2010

Whilst there has been much debate about the contribution of antibiotic use in veterinary medicine to the overall resistance development in human pathogens, these data suggest that clinical resistance to fluoroquinolones in E. coli and nontyphoidal Salmonella is uncommon, except for a few countries.

33 Travelling is the origin of salmonellosis dues to Salmonella enterica sérotype Kentucky ST198 & resistance to ciprofloxacin

What could be the human health consequence of exposure to resistant zoonotic bacteria 34

35 Impact of AR on the human mortality due to salmonellosis

Macrolide resistance in Campylobacter jejuni and Campylobacter coli

37 Q3: What are the transmission pathways between animals and man

38 Pathways of transmission between animals and man Slaughter house meat Direct professional risk Soil Water Air 3 possible pathways Environment

39 Campylobacter: prevalence The food chain is a critical pathway for resistance transmission of resistance from animal to man Prevalence: % in feces Prevalence: 0-32% for carcass Prevalence: 0- <5% for meat

Prevalence of salmonella contamination (EU 2009) 40 The high prevalence in poultry is due to some anatomical and physiological specificcity

Several critical steps when processing chickens Feed withdrawal –Not too long, not too short Collecting and transportation of the chickens –Stacked several raw high and top to bottom contamination during transportation Feather removal –Scalding tanks to remove the feather Removal of the internal organs –Carcass contamination

Transportation of poultry –Campylobacter : Top to bottom contamination by feces during transportation

Feather removal in a contaminated environment by feces (scald tank)

Contamination of the carcass During evisceration, some degree of faecal contamination is inevitable no matter how stringent the hygiene measures that are applied

45 Direct transfer from animal to man (professional risk ) Also direct contact with antibiotic

The case of Methicillin- Resistant Staphylococcus Aureus (MRSA) 46

MRSA

MRSA prevalence in animals There are differences in the occurrence of MRSA between companion animals (pets and horses) and livestock (mostly pigs, poultry, cattle and sheep).

MRSA: animal reservoir The most common MRSA isolates from animals are ST398, the main reservoirs being pigs and veal calves. –This type, which is also isolated from chickens and horses, can be transferred to humans. –There is a limited overlap with humans, and transmission to humans is rare. – Most isolates are multidrug resistant, and some PVL- positive isolates are found. MRSA is rarely found in meat and then only in low quantities; the source is thought to be the butcher/meat handler rather than animals

MRSA in pigs The prevalence of MRSA-positive herds was 67% in breeding herds and 71% in finishing herds. The most likely explanation for the observed increase in MRSA-positive herds is that MRSA is easily transmitted between herds (e.g. when purchasing animals).

MRSA in pigs

MRSA: Risk factor analysis

Risk factor analysis Multivariable logistic regression analysis was then performed on data from 171 breeding herds. The number of MRSA-positive herds increased from ∼ 30% at the start to ∼ 75% at the end of the study, most likely due to transmission between herds. The prevalence of MRSA increased with herd size, as ∼ 40% of smaller herds ( 80% of larger herds (>500 sows). Other risk factors (e.g. antimicrobial use, purchase of gilts and hygiene measures) were not significantly associated with MRSA, though associated with herd size. Herd size appeared to be a compilation of several factors, which made larger herds more often MRSA positive

MRSA carriage in veal calves Prevalence in veal calf far higher than in adult cow. A study carried out on 102 farms in the Netherlands found that 28% of calves carried MRSA and 88% of the farms sampled had calves with MRSA. The farmers and their family members were also sampled, and 33% of the farmers carried MRSA but only 8% of family members. –The isolates from both animals and humans belonged to the clonal complex ST398.

MRSA in calf Studies in humans show an association between antimicrobial use and the occurrence of MRSA, and batch-treated calves were more often MRSA positive than untreated calves

Pfizer Paris MRSA colonization is an occupational risk for veterinary professionals To read the full article MRSA was isolated from nares of 27/417 (6.5%) attendees at an international veterinary conference: 23/345 (7.0%) veterinarians, 4/34 (12.0%) technicians, and 0/38 others.

57 Indirect transfer from animal to man via the butcher’hands : a consumer risk The case of MRSA

Hazard associated to the release of antibiotic in environment

Fate of antibiotics, zoonotic pathogens and resistance genes: residence time in the different biotopes Digestive tract: 48h Lagoon: few weeks Air pollution Bio-aérosol Air, water & ground pollution Ex:T1/2 tiamuline=180 days

Rate of antibiotic degradation in manure, soil, waste… AntibioticsmatrixDégradation %Days ChlortétracyclineCattle manure2484 TétracyclinePig manure5048 OxytetracyclineSoil+contam manure0180 OxytetracyclineSediment slurry, aeobiose 5043 TMPSewage sludge SulfamidesManure/sludge028 Aminoglycosidesmanure030 Tiamuline 5026 TylosinePig manure, anaerobic 502 BacitracinSandy loam & manure7730 EnrofloxacinCattle mannure<156

61 Sewage production in a pigs setting Annual sewage production is about tons per sow unit i.e. about 1500 to 2000 tons of sewage per year for a setting of 100 sows

62 Hazard associated to the release of antibiotic in environment Resistance selection conditions are also present in the environment. Contributes to antimicrobial resistance Spread

Risk associated to bioaerosols Studies of bioaerosols inside intensive pig farms have shown more than 90% had multi-drug resistance.*,** Antibiotic resistance bacteria have been recovered 150 meters downwind from intensive pig farms.** Swine workers and veterinarians have elevated carriage of MRSA (methicillin- resistant Staphyloccoccus aureus).*, *** *A.Chapin, et.al, Airborne Multidrug-Resistance Bacteria Isolated from Swine CAFO, **S.G. Gibbs, et.al. Isolation of Antibiotic-Resistant Bacteria Downwind of Swine CAFO, 2006 *** Wulf, M, et.al. MRSA in Veterinary Doctors and Students in Netherlands, 2006

Environ. Sci. Technol. 2010, 44, 580–587

65 Sewage management is in order Anaerobic digestion destroyed only 59% of oxytetracycline in manures in 64 days. However, composting destroyed 95% of oxytetracyline in manures within first week. Also, levels of oxytetracycline resistant bacteria were 10-fold lower

66 Hazard due to the presence of antibiotic residues in food No public health issue – No observance of the withdrawal time – Inappropriate withdrawal time (generics) – Surveillance from the french ministery Positive sample: 0.3% for antibiotics and 0.4% for sulfamides Many control for milk (technological risk for chees production etc.)

Antimicrobial resistance: risk management options Ispaia

Risk management for the veterinary contribution to the human resistance: precaution principle or prevention principle? Rem: WHO do not consider that transmission of such organisms or their genes must be proven, but only the potential for such transmission to occur (precaution principles)

Precaution principles

Prevention principle

Reduction of antibiotic consumption

72 Sales of veterinary antibacterial agents for different species 43.9% 16.1% 7.8% 1.83% 0.51% 22.5% 7.18 France 2009 Tonnage total en 2009= 1067 Tonnes

How to reduce antibiotic consumption 1.Suppress incentives to antibiotic consumption 1.Generics 2.Low price 3.Turnover for the veterinarians

Consequences of generic marketing on antibiotic consumption and the spread of resistance

75 Generics and antibiotic consumption

- 76 Number of ciprofloxacin trade names (black line) and the median price per DDD (red line) and the influence of the introduction of generics

PL Toutain Ecole vétérinaire Toulouse The influence of the introduction of generics on the total use of ciprofloxacin (black line) and median price per DDD (red line)

PL Toutain Ecole vétérinaire Toulouse Trends in the frequency of ciprofloxacin resistance among E. coli urine (brown line) and the consumption of ciprofloxacin (black line) from 1995 to 2005

Use of fluoroquinolones in veterinary medicine: Germany, DK, UK From Hellmann: Assoc Vet Consult. SAGAM 2005

Use of fluoroquinolones in veterinary medicine: Eastern EU, Spain, Portugal From Hellmann: Assoc Vet Consult. SAGAM 2005

How to reduce the antibiotic consumption: reconsider some dosage regimens

Diseasehealth Therapy Metaphylaxis (Control) Prophylaxis (prévention) Growth promotion The different modalities of antibiotic uses in food producing animals High Pathogen load Small No NA Antibiotic consumption Only a risk factor

MICs estimated with different inoculmum densities, relative to that MIC at 2x10 5 Ciprofloxacin Gentamicin Linezolid Daptomycin Oxacillin Vancomycin

Materials and methods Progression of infection Inoculation of Pasteurella multocida 1500 CFU/lung Time (h) Bacteria counts per lung (CFU/lung)

Materials and methods Progression of infection early (10h) Administration Late (32h) Administration Inoculation of Pasteurella multocida 1500 CFU/lung Time (h) Bacteria counts per lung (CFU/lung) no clinical signs of infection anorexia lethargy dehydration

% 1 mg/kg Marbofloxacin doses 40 mg/kg early late Marbofloxacin administrations Pourcentages of mice alive contro l 1-Clinical outcome (survival) A low early dose better than a late high dose

2-Bacterial eradication Early low dose= late high dose % % of mice with bacterial eradication 1 mg/kg Marbofloxacin doses 40 mg/kg Early Late Marbofloxacin administrations control

3-Selection of resistant target bacteria A late 1 mg/kg marbofloxacin dose select resistance (observation at 16 or 38h after the marbofloxacin administration) % +38h observation 16 hours after marbofloxacin administration = 48 hours after the infection = like early administration 1 mg/kg Marbofloxacin doses 40 mg/kg % of mice with resistant bacteria control Early late Marbofloxacin administrations +38h 1 mg/kg 40 mg/kg

For a same dose of marbofloxacin, early treatments (10 hours after the infection) were associated to – more frequent clinical cure – more frequent bacteriological cure – less frequent selection of resistant bacteria than late treatments (32 hours after the infection) Conclusion Early administrations were more favourable than late administrations

Metaphylaxis and Very Early Treatment (VET) I suggest to replace metaphylaxis by VET because metaphylaxis convey negative values – Confuse with mass treatment, – Confuse with prophylaxis

When to finish a treatment? ASAP Should be determined in clinics Should be when clinical cure is actually achieved Should not be a hidden prophylactic treatment for a possible next infectious episode

Conclusion: What is the most dangerous situation? Eating pork Travelling Licking