Dr. Terry Dwelle - Antimicrobial Resistance: What Can We Do?

ANTIMICROBIAL RESISTANCE WHAT CAN WE

DO?Terry L Dwelle MD MPHTM FAAP CPH

State Health OfficerNorth Dakota Department of Health

2

Antibiotic Era

Antibiotics first employed in the 1940’s Antibiotics + Vaccination + Sanitation =

Marked decline in deaths from ID’s Antimicrobial resistance is a major ID

threat to PH Much attention given to nosocomial

infections – ie VRE Community acquired resistance is rising –

St Pneu., E Coli, Salmonella, etc. Is an evolving problem – spans all health

care settings.

Major antibiotic categories Aminoglycosides Beta lactams – penicillins, cephalosporins, carbapenems,

monbactams Flouroquinolones Glycopeptides Ketolides Lincosamides Macrolides Oxazolidinones Streptogramins Sulfonamides Tetracyclines Levomycetinums Ionophores Bambermycins Polypeptide s

Why we use antibiotics?

Treat infections – animals and humans Prevent infections

Humans - surgical wounds, dental prophylaxis for endocarditis, neutropenia

Animals – prevent disease when animals are susceptible

Promote growth – cattle, poultry and swine

World Hunger

Developed Countries; 19; 2%

NE and N Africa; 37; 4%

Latin Am and Carribean; 53;

6%

SS Africa; 239; 26%

Asia and Pacific; 578; 62%

925 million hungrypeople in 2010, 13.7 % ofthe 6.8 billion peoplein the world

Children at risk

160 days of illness per year ½ of the 10.9 million deaths per year Magnifies the effect of diseases like

measles and malaria

Antibiotics and Animal growth

Swine – 3-9% improved weight gain, 3-7% improved feed efficiency.

Greatest benefit when feed composition, management practices and health status of animals is not optimal.

Action Eliminate bacteria that steal essential nutrients Reduce competition with beneficial bacteria that

produce essential nutrients for the animal. Control growth of bacteria that cause low-grade

infections or produce toxins – decreasing nutrient absorption.

Antibiotics used for animal growth

Human and Animal Tetracyclines Sulfonamides Penicillins Macrolides Fluoroquinolones Cephalosporins Aminoglycosides Chloramphenicols Streptogramins Polypeptides

Animal only Ionophores Bambermycins

Resistance

Strep. Pneumoniae Moraxella Catarrhalis Hem Influenza Type B Strep Pyogenes E. Coli Neis. Meningitidis Campylobacter Salmonella Shigella Staph Aureus Enterococcus Mycobacterium Tuberculosis Pertussis

10

Reasons

Inappropriate antimicrobial prescribing – most important Overuse – 30-60% prescriptions are

inappropriate Inappropriate dosing Use of broad spectrum AB’s as first line Rx

Animal applications (food)

11

Prescriptions - 1992Adults Prescribing Rates

Colds 51%

URI 52%

Bronchitis 66%

Children

Colds 44%

URI 46%

Bronchitis 75%

Gonzales R et al JAMA 1997:278:901-904. Nyquist AC et al JAMA 1998;279:875-77

12

Broad Spectrum Antibiotic Use

• 46% of patients with common cold or non-specific URI’s received antibiotics

• Broad spectrum antibiotics used; 54% general, 51% colds, 53% sinusitis, 62% acute bronchitis, 65% OM

• Lower BS use – blacks, lack of insurance, HMO membership

• Greater use of BS- Northeast and South

JAMA 2003;289:719-725

13

Patient Pressure

12% recently taken antibiotics 27% believed taking antibiotics during a

cold made them better 32% believed taking antibiotics during a

cold prevented more serious illness 48% expected antibiotics when seeking

medical care with a cold 58% not aware of the health risks of

antibiotics

Emerg Inf Dis: 9;9, pp 1128-1134 – JD Eng, et al

14

Veterinary Usage

Human health hazards Antibiotic resistance particularly with low

dosing (ie Salmonella) Glycopeptide resistant E faecium of animal

origin – find in stools for 14 + days after ingestion of meat

Cross resistance ie Virginimycin and Quinupristin-dalfopristin

in enterococci

Sorensen TL, NEJM 2001;3435:1161-6, Welton LA et al AntiAgChem 1998;42:705-8

15

Veterinary Usage Continued

Human Health Hazards Salmonella enterica (flouroquinolone resistant)

spread from swine to humans in meat

Chiu CH NEJM 2002;346:413-9

Association of Animal Antibiotic use and Antibiotic resistance in

humans Europe – 1990’s – Avoparin use

associated with vancomycin resistance in humans

US – 1990’s – Campylobacter resistance to fluoroquinolones

What can be done?

Use antibiotics only when indicated Least broad spectrum antibiotics first Least time exposure possible Use adequate therapeutic doses Use non-human antibiotics when possible With crossover drugs use those where

potential resistance will have the least impact on humans

Appropriately monitor cultures and sensitivities

18

Resistance Reversal - Iceland

PRSP rose from 0% (1988) to 20% (1993) Information campaign – physicians Regulatory change – patients paid for

prescription drugs PRSP declined to 15% (1995)

Stephenson J, JAMA 1996;275-175, Gunnlaugsson A, AntiAgChem Conf, 1999, Abstract 1026

19

Resistance Reversal - Finland

Macrolide use tripled in the 1980’s Erythromycin resistance for Gp A strep

rose sharply (17%) in the early 1990’s National campaign for physicians Resistance declined to 9% from 1992 to

1996

20

Resistance Reversal - Med Center One

1980’s Appropriate use of advanced spectrum

antibiotics – 65% All advanced spectrum antibiotic orders

received a form to be completed within 24 hours (justification of usage)

No adequate response – consult or could result in loss of privileges

Appropriate use increased to > 95%

Resistance Reversal – Animal Antibiotic usage

Europe – Vancomycin resistance Denmark – reduction in resistance in E

Faecium in broiler chickens (from 60-80% to 5-35%) WHO Internation Panel Ruling, Nov, 2002)

22

Tactics

Public Information Campaigns Intensive Information Campaigns for

Physicians Proactive Hospital Antibiotic Usage

Programs Collaborative task force – Veterinarians,

Physicians, and Public Health