• What are drug-resistant organisms?
• Are DROs a new problem?
• Will I get sick if I come in contact with a DRO?
• What are some risk factors for being infected or colonized by a DRO?
• How are DROs spread?
• What are ways to control the spread of DROs?
• What precautions might be in place if I work in a hospital?

What are drug-resistant organisms?

Drug-Resistant Organisms (DROs) are bacteria and other organisms that have developed a resistance to certain drugs. In other words, a particular drug is no longer able to kill or control a specific bacteria or organism. Other terms used to describe this situation include antibiotic resistance, antibacterial resistance, and antimicrobial resistance.

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), and
• MDR-TB - multidrug-resistant tuberculosis.

Are DROs a new problem?

No. Penicillin resistance to Staphylococcus aureus was first noted in the 1940s. Wide spread use of antibiotics plus the natural evolution of bacteria over time has lead to a number of drug-resistant strains emerging.

Will I get sick if I come in contact with a DRO?

Not necessarily. If you are sick, you are considered to be "infected". Infection means that the organism or bacteria is present in or on your body and that it is causing an illness or other medical condition.

In some cases, it is possible for the organism to be present but not causing illness. Such cases are called 'colonization'. For example, Staphylococcus aureus is commonly found in various areas of the body including the nose. Colonization rarely becomes an infection unless the bacteria is spread to a different and susceptible part of the body.

What are some risk factors for being infected or colonized by a DRO?

In general, people who are healthy are at low risk of becoming colonized or infected. Casual contact such as hugging and touching with a person who has a DRO is considered okay (Centers for Disease Control and Prevention, 2000). If in a hospital, however, it is still important to wash your hands before you leave the patient's room (or when visiting with an infected or colonized person in order to prevent the organism from spreading).

The risk of colonization and infection are increased if you have:

• an existing severe illness,
• an underlying disease or condition is present such as
  • chronic renal disease
  • insulin-dependant vascular disease
  • dermatitis or skin lesions
• previous exposure to antimicrobial agents,
• undergone an invasive procedures such as dialysis and catheterization,
• repeated contact with the healthcare system,
• a long stay in a hospital,
• previous colonization by a DRO,
• or if you are elderly or are on immune-suppressing medication.

How are DROs spread?

DROs spread the way other bacteria and organisms spread. Contact (touching) devices or surfaces contaminated with body fluids from an infected person or direct hand/skin contact are the most common routes of exposure.

What are ways to control the spread of DROs?

The Centers for Disease Control and Prevention (CDC) states that there is little risk of transmitting these organisms outside of a hospital or health care setting and that healthy persons are at low risk of infection. One of the best ways to control the spread of bacteria, organisms, and other infections is to wash your hands with soap and warm water for at least 10-15 seconds. Please see the OSH Answers document, Hand Washing: Reducing the Risk of Common Infections for more information.

If you are visiting a person in a healthcare setting (such as a hospital or a long-term facility), you should:

• wash your hands before leaving the person's room
• wear disposable gloves if contact with body fluids is expected. Gowns should be worn if excessive contact with bodyfluids is possible.

Outside of a healthcare setting, if you come in contact with a person who is infected or colonized (such as caring for aninfected person in your home, or in a first aid situation), the CDC recommends the following precautions:

• Caregivers should wash their hands with soap and water after physical contact with the person and before leaving the home.
• Towels used for drying hands after contact should be washed before re-use.
• Disposable gloves should be worn if contact with body fluids is expected. Hands should be washed after removing the gloves.
• Bed sheets should be changed and washed if they are soiled, and on a regular basis.
• The patient's environments should be cleaned routinely and when soiled with body fluids or feces. A commercial disinfectant or a solution of 1 part bleach in 100 parts water is recommended.
• Notify doctors and other health care personnel who provide care for the patient that the patient is colonized/infected with a drug-resistant organism.

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

Because a health care worker will help many patients during a shift, it is important to follow certain steps to control the spread of infection. You should check with your infection control department for any specific requirements.

In general, these methods include:

• Isolation - where the patient is given their own room, or share a room with others that have the same infection.
• Restrictions on where the patient can be transported or moved.
• Gloves and Hand washing - wear gloves and wash your hands after contact, especially contact with body fluids. You may have to change gloves and wash your hands between procedures on the same patient to prevent cross-contamination to different body sites.
• Masks/Gowns - depending on the level of contact with body fluids or feces, all or some of these protective clothing will be required
• Use equipment properly - make sure that any equipment used is appropriately cleaned, disinfected, or discarded. Surfaces of equipment in the patients room should also be cleaned and disinfected.
• Special "dedicated" equipment may be required. Use of instruments such as stethoscopes, bedside commodes or thermometers may only be allowed with one patient or one group of patients.
• Handle and clean laundry properly.
• Special procedures may be in place for testing and surveillance to monitor the infection.

Document last updated on March 13, 2003

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