Presentation on theme: "Juan J Carrique-Mas Oxford University Clinical Research Unit"— Presentation transcript:
1 Use and misuse of antimicrobials on farms: Ecological and health impact Juan J Carrique-MasOxford University Clinical Research UnitHo Chi Minh City, VietnamBiodiversity and Health SymposiumPhnom Penh, 17 November 2014Good morning. It is a pleasure to be in PP introducing this very relevant topic.
2 Agenda AMR: A complex ‘ecohealth’ problem Economic development and animal productionThe ‘ecological web’ of AMROther AMR co-selecting environmental pollutantsData from current projects (OUCRU-VN):Antimicrobial consumptionTransmission of AMR between humans and animalsThe way forwardFuture projectsIn my presentation I will introduce the problem of AMR – emphasizing its complexity.Use of Ams are interlinked with animal production and economic development.I will present the ecological web of AMR. I will briefly introduce to the issue of other co-selecting pollutants.Then some results from on-going projects in VN that hopefully will help document the issues, both on AM consumption on farms and transmission between humans and animalsFinally some suggestions as to where to move on from here.
3 The ‘Confusogram’?????This diagramme comes from a book by Dr Prescott of Guelph University in Canada. In another publication it was referred as a confusogram.It highlights the complex webs of circulation of AMR. It is a One Health issue, probably more than any other.The overwhelming majority of research on the right side, hospitals and communities. Over the last 15 years or so emphasis on the food producing animals.Clearly the greatest research gaps on research relate to the environment.J. F. Prescott et al. (2000) Antimicrobial Therapy in Veterinary Medicine
4 The VAC system in Vietnam We can see an example of this web in some producting systems in Asia. For example in Vietnam, the VAC system, stands for garden, pond, and animal pen which is an efficient way of recycling byproducts and manure, but also for facilitating AMR.Source: FAO (2004)
5 Human and farm density in SE Asia* Animal protein consumption: VietnamFish and shrimp production in Vietnam (2004 to 2011)Human and farm density in SE Asia*Pig farmsChicken farmsHumansThese maps are now a little bit old, but show how the densities of humans, chicken and pigs are inter-related.Of the countries in the Indochina Peninsula, probably VN has the highest population densities, mostly in the Deltas and the cities of Ha Noi and HCMC. An important characteristic is the rapid observed increase in animal protein consumption, fuelled by fish (now VN is one of the first fish consuming countries in Asia), followed by pigs and poultry* Sources: LEAD and FAO (2000, 2006)
6 Antimicrobial use in animal production Fundamental differences in the use of AM in humans and animals. Use in animal production is almost always related to groups of animals,except in the case of injectable drugs (most common in pigs only, but rare in aquaculture and poultry).Growth promotion, prophylactic and methaphylactic use, treatment. In human medicine treatment is the most common use.Some travellers have the habit of having doxacycline in developing countries.S. Page and P. Gautier (2012), Rev. sci. tech. Off. int. Epiz., 2012, 31 (1),
7 Post antimicrobial effects Fate of antimicrobialsFate of antimicrobial resistant bacteriaFate of resistant genesInteraction with environmental bacteria?Fate of antimicrobialsDistribution at sub-inhibitory concentrationsFate of antimicrobial resistant bacteriaPathogens and commensalsDirect transfer from host to hostIndirect transfer (food, water, environmental pathways)This slide summarises the main impacts of the use of AM:It concerns that availability of the antimicrobial that may keep promoting AMR after its intended aid. As a result of AMU you generate AMR bacteria that may reach humans or other individuals not treated.Now the most recent concern is that a lot of the AMR promoted during the use of AM is in the form of AMR genes that can cross beyond bacterial species.Fate of resistant genesVertical transferHorizontal transfer between unrelated bacteria*Adapted from Da Costa et al. (2013) Int. J. Environ. Res. Public Health 2013, 10:
8 AMR and environmental bacteria Environmental bacteria >95% of the earth’s microbiomeNaturally produce antimicrobials as signalling molecules at low concentrationsNaturally multi-drug resistantMost plasmid-mediated ARG originate from the environmenti.e. qnr from waterborne bacteriaSince 1950’s humans have manufactured antimicrobials and used them at industrial levels, this results in unprecedented levels of exposure of the earth’s microbiome to antimicrobials
9 Ecological concernsCommensal, pathogenic flora, and ARG interact with environmental organisms in certain hotspotsFarm, hospitalARG integrated in gene-transfer elements (plasmids, transposons, integrons) the highest riskARG can be maintained in the absence of antimicrobial selective pressure and co-selected due to other stressors (siderophores, toxins, heavy metals, biocides)Do changes in the natural ecosystems as a consequence of human activities accelerate evolution towards AMR?ARG detected in bacteria from environmentally pristine locations, indicating disseminationqnr encoded in plasmids detected in Aeromonas spp.† J. Martinez (2009). Proc. R. Soc. B.
10 Confirmed hospital-acquired Acinetobacter baumannii infections, respiratory patients, ICU (HTD, HCMC (Vietnam) ( )Source: James I. Campbell, OUCRU-HCMC
11 AMR in E. coli in humans and chickens in the Mekong Delta Tien GiangI will be presenting some studies we have been carried out to investigate AMU in poultry farms, and AMR in chickens and humans
12 VIBRE Project Rural areas (3 districts) Urban areas (1 city) Chicken farmUse of antimicrobialsFood habitsUse of antimicrobialsFood habitsKnowledge and use of antimicrobials:Bio-securityNon-farmers (N=204)Not involved in poultry farmingMatched by commune, age/sex to farmerUrban inhabitants (N=102)Not involved in poultry farmingLiving in urban centre of My ThoChicken farms(N=204)Development of AMR E. coli ?Transfer of AMR?Use of antimicrobialsContact with chickensFood habitsChicken farmers(N=204)Transfer of AMR?
13 Antimicrobial agents used in chicken farming, TG Class of antimicrobialName of antimicrobialNo. (%) formulations containing the product (N=157)No. (%) farms using (N=208)TetracyclinesDoxycycline, oxytetracycline, tetracycline57 (36.3%)53 (25.5%)PolypeptidesColistin48 (30.6%)41 (19.7%)MacrolidesTylosin, tilmicosin, erythromycin, spiramycin40 (25.5%)40 (19.2%)PenicillinsAmpicillin, amoxicillin41 (26.1%)34 (16.3%)QuinolonesFlumequine, oxolinic acid, norfloxacin, enrofloxacin22 (14.0%)19 (9.1%)AminoglycosidesSpectinomycin, neomycine, gentamicin, apramycin, streptomycin19 (12.1%)PhenicolsFlorfenicol, thiamphenicol14 (8.9%)12 (5.8%)Sulphonamides/trimethoprimSulfamethoxazole, sulphadimidine, sulphadimetoxine, sulphadimerazine, trimethoprim12 (7.6%)LincosamidesLincomycin4 (2.5%)PleuromutilinTiamulin1 (0.6%)1 (0.5%)Studies show that over the last 90 days a total of 28 formulations had been used. Some of them includecritically important antimicrobials such as colistin, quinolones and aminoglycosides.
14 Antimicrobial formulations, TG PenicillinPolypeptideMacrolidesTetracyclinesQuinolonesPhenicolsAminoglycosidesSulphonamidesLincosamidesPleuromutilinsNo. administrationsPenicillins633141Polipeptides25348254401375720228141912Pleuromutilintylosin tartrate,trimethoprim,sulphadiazine, sulphamethoxazole100/157 (64% products were ‘mixes’ of 2 or more antimicrobials)
15 AMU on chicken farms, Tien Giang VariableLevelAll farms (N=208)Number of antimicrobial products used over study period40.9%1>118.3%Method of administrationWater82%Feed9%Feed and water4%Type of administrationProphylaxis84%Treatment12%BothTimingOn arrival34%Continuously18%Periodic29%Other19%Advice given byDrug seller56%District veterinarianFriend/neighbourSales person2%We collect data on AMU on these farms
16 Antimicrobial consumption in relation to chicken production StratumNo. farms sampledNo. chickens sampledNo. chickens (census)Fraction sampled(%)Sampling weightMilligrams of active compound used per week per chicken (±SE)Grams of active compound per 1,000 chickens producedCG, hh342,890409,8500.007141.830.4 (±15.6)901.2 (±622.8)CG, sm47,970128,2500.3742.75.3 (±1.5)167.5 (±63.9)CT, hh364,505268,2950.01759.55.6 (±1.4)327.8 (±122.4)CT, sm50,23056,7000.8861.118.6 (±7.2)193.1 (±57.3)MT, hh2,29058,3100.03925.526.4 (±17.2)413.8 (±256.4)MT, sm52,50073,3000.7161.44.7 (±1.9)156.6 (±63.7)All208160,385994,7050.16115.1 (±4.0)358.1 (±113.5)
17 What’s on the menu? Colistin: 120 mg/Kg Neomycin: 400 mg/Kg Florfenicol: 60mg/KgKitasamycin: 300 mg/KgIn Vietnam, most commercial animal feed rations are medicatedHow easy it is to calculate the amount of AM necessary to produce pork
18 AMR testing in E. coli Disc diffusion test 1 ampicillin (10µg) 2 ceftriaxone (30µg)3ceftazidime (30µg)4chloramphenicol (30µg)5ciprofloxacin (1µg)6ciprofloxacin (5µg)7trimethoprim-sulphamethoxazole (1.25 µg /23.75µg)8gentamicin (10µg)9amikacin (30µg)10meropenem (10µg)11amoxicillin-clavulanic acid (20/10µg)12tetracycline (30µg)Disc diffusion test
19 Antimicrobial resistance in E Antimicrobial resistance in E. coli (non-selective plates) VIBRE ProjectThese can be taken as ‘randomly selected colonies from farmers and chickens’.
20 Diversity among chicken and human E. coli N=5 colonies per study subjectShannon-Weaver diversity index (H)Shannon-Weaver index (H)
21 Human and chicken E. coli AMR patterns (I) 12345---C--TE-STX----AMP-AMC---C AMP-AMP----C--TE-STX----------TE---------C--TE-----AMP-XMatching: 3/50 (6%)
22 Comparisons of E. coli patterns from humans and chickens DistancesNo. calculationsMedian [75% IQR]Chicken vs. farmer a2012.76 [ ]Chicken vs. rural control b1993.12 [ ]Chicken vs. urban control c973.47 [ ]Farmer vs. Rural control d1963.02 [ ]Farmer vs. Urban control e953.20 [ ]Rural vs. Urban control f3.25 [ ]
24 AMR among pig pathogens (n=53) Source: Severe disease in piglets in southern Vietnam: main bacterial aetiologies and antimicrobial resistance. J. Campbell et al, 2014 (in preparation)
25 Longitudinal studies on AMR in pig and chicken farms Differences in the dynamics of AMR depending on the type of farming. Here we see results of AMR testing against a number of antimicrobials for one pig and poultry farm at three time points.E. coliEnterococcus spp.White bar: day-old, grey bar: mid production, black bar: end of production
26 Environmental stressors and AMR: Quaternary ammonium compounds (QAC)
27 Use of QAC in chicken farms ProductDisinfectant classPercent farms using (%)(N=208)1QAC68.22Peroxygen-based3.43Halogen-Releasing agent 14Halogen-Releasing agent 21.95Other23.0(in the cleaning process and in occupied animal houses)QAC products represented 68.2% of all disinfectants used in Tien Giang provinceBenkocid represented 56.7%The cross-resistance of QAC and antibiotics could be achieved by linkage of different resistance mechanisms on the same plasmid, transposon or integron or any combination of these . Many bacteria acquire resistance to QACs by changing the composition of their membrane proteins, LPS, fatty acids [6, 9], cell surface hydrophobicity
28 Adaptation experiments to QAC Determine MIC for each isolateExpose 105 cfu/ml of bacteria to 0.5MIC (37oC, 18-20h)Stabilise bacteria in MHB without disinfectant (37oC, 5h)Calibrate suspension to 105cfu/ml and transfer to new MHB supplemented with 0.75 MIC QAC disinfectantStabilise bacteria in MHB without disinfectant for 5h at 37oCExpose bacteria to step-wise increase concentration of disinfectantUntil no growth observed, the highest concentration of disinfectant that bacteria can survive were used
29 Cross-resistance QAC and antimicrobials Study IDTECNAMPCIPCTSXTCAD01-cSIAD01-pRAD01-efAD02-cAD02-pAD02-efAD03-cAD03-pAD03-efAD04-cAD04-pAD04-efAD09-cAD09-pAD09-efAD10-cAD10-pAD10-efc = control; p = post adaptation; ef= after treating with PAβN
30 The link between AMU and AMR is uncontroversial Chantziaras et al (2014) Journal of Antimicrobial Chemotherapy, 69:
31 A vociferous skeptical minority WoK quoted >350 times!!!
32 Priorities for research….and for policy Carry out farming with less antimicrobialsIf antimicrobials are used, limit their impact on animals and their environmentUnderstand why and where antimicrobials are used in agricultureIncrease awarenessChange attitudes and behavioursSurveillance of AMU and AMR:Monitoring of antimicrobial use and ARGApplied researchUnderstand impact of antimicrobial use on the environmental (AM, ARG, bacteria)Intervention studies to reduce AMUTechnical solutions to limit impact.. and test them!
33 Acknowledgements Zoonoses Group ITU, CTU, Microbiology, Enterics Group Mr. Trung Nguyen VinhDr. Ngo T. HoaMr. James CampbellDr. Constance SchultszSub-Department of Animal Health Tien Giang, Dong ThapHospital Tropical Diseases HCMCFunding:ZoNMW / WOTRO (The Netherlands) (VIBRE Project)The Wellcome TrustAdd pictures