Bacterial resistance against antibiotics

and it’s preventionBy:ZARA KHASROWSHERWAN RAZAQWTAR OMER

What Are Antibiotics? Antibiotics, also known as antibacterials, are types of medications that destroy or slow down the growth of bacteria

There r 2 types of antibacterials:

Spectrum of Activity

Broad spectrum antibacterials

Narrow spectrum antibacterials

Mode of Action

Mode of Action

Mode of Action

Inhibitors of other metabolic processes.

Other antibiotics act on selected cellular processes essential for the survival of the bacterial pathogens.

How to use antibiotics?

orallyinjection

applied directly to the affected part of the body.

or

Some antibiotics should not be consumed with certain foods and drinks. Others should not be taken with

food in your stomach - these would normally be taken about an hour before meals, or two hours after.

Antibiotics are appropriate to use when :

1.There is a known bacterial infection 2.The cause of the infection is unknown and bacteria are suspected.

ANTIBIOTICS KILL BACTERIA, NOT VIRUSES

If a virus is making you sick, taking antibiotics may do more harm than good.

most respiratory tract infections are caused by viruses, so antibiotics won’t have any effect.

What kinds of infections are caused by viruses and should not be treated with antibiotics?

• colds• Flu • Most coughs and bronchitis • Sore throats • Some ear infections

1.Diarrhea

2.Feeling and being sick

3.Fungal infections of the mouth, digestive tract and vagina

What are the side-effects of antibiotics?

Rare side-effects of antibiotics:1. kidney stones 2.Abnormal blood clotting 3.Sensitivity to sun

5.Deafness4.Blood disorders

Antibiotic

Resistance

Antibiotic resistance occurs when an

antibiotic has lost its ability to

effectively control or kill bacterial

growth

It is a specific type of drug resistance.

Multi-drug resistant (superbug)• When bacteria resist to several types of

antibiotics • Due to plasmids• shigella (sul,chlo,str,tetra) • MRSA (hospital) • TB (tuberculosis)

DEVELOPMENT OF RESISTANCE• Bacterial cells that have

developed resistance are not killed off.– They continue to divide– Resulting in a completely

resistant population. • Mutation and evolutionary

pressure cause a rapid increase in resistance to antibiotics.

There are two types of resistance;1-Natural Resistance: Bacteria may be inherently carrying resistant genes • Streptomyces • Penicillin

2-Acquired Resistance:

.Mutations

. mobile genetic elements

•Examples of drug-resistant organisms include:

•MRSA - methicillin/oxacillin-resistant Staphylococcus aureus

•VRE - vanomycin-resistant enterococci

•ESBLs -extended-spectrum beta lactamases (resistant to cephalosporins and monobactams)

•PRSP - penicillin-resistant Streptococcus pneumoniae

•GISA - glycopeptide-intermediate Staphylococcus aureus

•VISA - vancomycin-intermediate Staphylococcus aureus

•VSRA - vancomycin-resistant Staphylococcus aureus (not yet found in nature, but it is believed it will emerge or evolve from VISA),

•MDR-TB- multidrug-resistant tuberculosis.

LIST OF DRUG-RESISTANT BACTERIA

How bacteria become resistance?

1. Inappropriate Use One of the main causes of

antibiotics drug resistance is antibiotic overuse, abuse, and in some

cases, misuse, due to incorrect diagnosis.

2. Inadequate Diagnostics

3. Hospital Use 4. Agricultural Use

Scientists also believe that the practice of adding antibiotics to agricultural feed promotes drug resistance.

Critically ill patients are more susceptible to infections and, thus, often require the aid of antimicrobials. However, the heavier use of antimicrobials in these patients can worsen the problem by selecting for antimicrobial-resistant microorganisms

5. Mutation During replication, mutations arise and some of these mutations may help an individual microbe survive exposure to an antimicrobial

6. Gene Transfer Microbes also may get genes from each other, including genes that make the microbe drug resistant. 7. Selective Pressure In the presence of an antimicrobial, microbes are either killed or, if they carry resistance genes, survive. These survivors will replicate, and their progeny will quickly become the dominant type throughout the microbial population.

Mechanisms of being resistant• (A) Chromosomal mutations:• 1. Reduced permeability. • 2. Enhanced efflux• 3. Enzymatic inactivation (beta-

lactamase)• 4. Alteration of drug target • 5. Loss of enzymes involved in drug

activation

• (B) Plasmid or transposon mediated:

How does antibiotic resistance spread?

vertically horizontally

Genetically, antibiotic resistance spreads through bacteria populations both "vertically," when new generations inherit antibiotic resistance genes, and "horizontally," when bacteria share or exchange sections of genetic material with other bacteria. Horizontal gene transfer can even occur between different bacterial species. Environmentally, antibiotic resistance spreads as bacteria themselves move from place to place; bacteria can travel via airplane, water and wind. People can pass the resistant bacteria to others; for example, by coughing or contact with unwashed hands.

Using antibiotics when you don’t need them may mean that they won’t work for you when you do need them in the future.

If you have an antibiotic-resistant bacterial infection:

1 32

•you will have the infection for longer

•you may be more likely to have complications of the infection

•you could remain infectious for longer, and pass your infection to other people, which increases the problem.

Can bacteria lose their antibiotic resistance?

• Yes sure • but this reverse process

occurs more slowly • By selective pressure1- adequate diagnosis 2-effective antibiotic 3-apropriate dose May take several months or even years

preventionCan you imagine a day when antibiotics don't work anymore?

It's concerning to think that:

could no longer workUnfortunately, the threat of untreatable infections is very real.

So how can we prevent bacterial resistance against antibiotics?

Optimize Use

PreventTransmission

PreventInfection

EffectiveDiagnosisand Treatment

PathogenAntimicrobial-Resistant

Pathogen

Antimicrobial Resistance

Antimicrobial Use

Infection

Key Prevention Strategies

Prevent infectionDiagnose and treat infection effectively

Use antimicrobials

wisely

Prevent transmission

Prevent infection

• Patients can do:Wash your hands frequently Don't share personal items Get vaccinated.

What else Patients can do:

•Take antibiotics exactly as the doctor prescribes.

•Only take antibiotics prescribed for you

•Do not save antibiotics for the next illness.

•Do not ask for antibiotics when your doctor thinks you do not need them

Prevent antibiotic resistance

Healthcare providers can:

•Prescribe correctly:

Bacteria and Viruses

On necessary

overlaps in antibiotics

Collaborate with each other and with patients

"Are these really necessary?"

"antibiotic timeout"

Stop and assess

What precautions might be in place if I work in a hospital?

Universal precautions:

•Hand hygiene

•Safe collection and disposal of sharps

• Gloves for contact with body fluids, non-intact skin and mucous membranes•Wearing a mask, eye protection and a gown if blood or other body fluids might splash

Avoid Needle Stick Injuries

We need to preserve this resource by

working together Because

No action today, no cure tomorrow

Antibiotics are invaluable resources

THANKS

• References:• 1.http://amrls.cvm.msu.edu/pharmacology/antimicrobials/effect-on-bacteria• 2.http://www.ccohs.ca/oshanswers/biol_hazards/drugresist.html• 3.http://www.nps.org.au/medicines/infections-and-infestations/antibiotic-

4.medicines/antibiotics-for-respiratory-tract-infections/for-individuals/what-is-antibiotic-resistance

• 5.http://www.medicinenet.com/antibiotic_resistance/page4.htm#causes_of_antimicrobial_drug_resistance

• 6.http://www.cdc.gov/features/antibioticresistance/• 7.http://www.abc.net.au/science/slab/antibiotics/resistance.htm• 8.http://www.tufts.edu/med/apua/about_issue/about_antibioticres.shtml• 9.http://www.cdc.gov/getsmart/antibiotic-use/antibiotic-resistance-

faqs.html• Book: Antibiotics the perfect storm by David M. shlaes