Infection Control for Dental Hygiene Students



Please read the material on this site carefully. When finished answering the post test questions, print out the answer page, record your answers, and bring the completed answer sheet to the Health Sciences Orientation.


Midlands Technical College
Prepared by
Cathy Milejczak, CDA, RDH, PhD
Updated by Lee H. Muthig, RDH, BA, MSDH (2014)


Infection Control for DHG and EDDA Students

Health care workers have a professional responsibility to patients, peers and themselves to practice appropriate infection prevention techniques. As a condition of employment health professionals must display knowledge of and the ability to practice appropriate infection control techniques. Lack of knowledge and application to practice infection control demonstrates unprofessional conduct. This course is designed to introduce all Midlands Technical College Dental Hygiene students to a basic understanding of blood borne pathogens, hazard communication and infection control as they enter their program of study. This course must be completed before entry into all clinical sites.

The course is designed to enhance the student's ability to comply with scientifically accepted principles and practices of infection control and to monitor compliance with OSHA's and CDC's recommendations concerning disease transmission in health care settings.  OSHA's Bloodborne Pathogen Standard applies to all occupational exposures to blood or other potentially infectious materials.

Upon completion of the course the student will be able to:

1. Demonstrate a basic knowledge of principles and practices of infection control.
2. Demonstrate an accurate perception of occupational risks and protective measures.
3. Create and maintain a safe environment for patient care.


DISEASE TRANSMISSION

The goal of Infection Control is to prevent the transmission of disease by implementing procedures to break the chain of infection.

Microorganisms such as bacteria, viruses, fungi, and parasites cause disease. Infection is the growth of an organism in a host (person) which may or may not produce any signs of illness. There are two types of diseases usually discussed, infectious disease and communicable diseases. Infectious diseases are the result of the microorganism invading the body. The term infectious means caused by a pathogen. Communicable diseases are ones that can be spread from one person to another. A disease can be infectious but not communicable.

METHODS OF TRANSMISSION

For a disease to be transmitted, the following four conditions must be met:

1. A microorganism (pathogen) is present.
2. There is enough of the microorganism to cause disease.
3. A person is susceptible to the pathogen.
4. The microorganism passes through the correct entry site.

HOW DISEASE ENTERS THE BODY

1. Direct contact- spread by direct contact with infected blood or body fluids from one person to another
2. Indirect contact- touching blood soaked gauze or contaminated equipment.
3. Airborne- a person coughs or sneezes
4. Vector borne- animal bites
5. Vehicle- from food or water.

HOW MICROORGINISMS ENTER THE BODY

1. Through mucous membranes- mouth nose, eyes, ears and genitals.
2. From needle sticks, broken glass.
3. Through non-intact skin- skin cuts, scratches, scrapes, burns, rashes, blisters, acne.

UNIVERSAL PRECAUTION

The safest way to prevent exposure to blood in the work environment is to take universal precaution. Universal precaution means to treat all blood and body fluids/ materials as if it is infectious. OSHA states that universal precaution should always be followed because some infectious diseases have a window period, patients may not disclose they have a disease or the patient may not even know they have a disease.  It is important to follow these precautions for all patients as they may not know they are infectious.
 Following universal precaution means to wear proper protection equipment and to follow infection control protocols. These precautions must be practiced if you are exposed to blood on a regular basis, or rare situations such as an injury to a co-worker.

STANDARD PRECAUTIONS

Standard Precautions is a newer term used to include not only blood but other body fluids, excretions, or secretions as well.  Thus the healthcare worker should wear proper protective equipment when exposed to or handling blood as well as all body fluids, secretions and excretions (except sweat).  It does not matter if these body fluids contain blood or not, but need to be considered infectious.  These Standard Precautions also pertain to nonintact skin as well as mucous membranes.  Remember, the health car worker should always wear Personal Protective Equipment (PPEs) when working with blood, all body secretions, fluids, excretions, nonintact skin, and mucous membranes as they may be infectious.


INFECTIONS MATERIALS

Infectious materials include blood, vaginal secretions, semen, cerebrospinal fluid (around the brain) pleural fluid (around the lungs), synovial fluid (around the joints), saliva from dental procedures, any fluid with visible blood, and any unidentifiable fluid.

NON-INFECTIOUS MATERIALS

Non-infectious materials include tears, sweat, sputum, urine, feces, vomitus, and nasal secretions.

MOST HARMFUL DISEASES TO HEALTHCARE WORKERS

Both bloodborne and airborne organisms can cause disease in health care settings, but bloodborne infectious organisms, like Hepatitis C and HIV, pose the greatest threat.

Hepatitis
Hepatitis is an inflammation of the liver. The most common forms of hepatitis are caused by alcohol abuse, drugs, or other chemicals and cannot be transmitted. Viruses can also cause hepatitis. There are at least six hepatitis viruses that cause clinically similar diseases: Hepatitis A, B, C, D, E, and G. The two most common types are A and B. Hepatitis A and E are mainly transmitted through contaminated food and water; Hepatitis B, C, D, and G are bloodborne diseases usually transmitted by direct contact with infected body fluids. Hepatitis also may be caused by excessive alcohol consumption, exposure to some hazardous chemicals, and as a complication of other viral infections. Hepatitis is known to live at least 7 days in dried blood. OSHA considers hepatitis a major health hazard. There is no known cure for hepatitis.

SYMPTOMS OF HEPATITIS
Initial symptoms:
• General fatigue
• Joint and muscle pain
• Loss of appetite
More severe symptoms
• Fever
• Nausea, vomiting
• Diarrhea or constipation
• Jaundice
• Cirrhosis of the liver

SOME FACTS ABOUT THE TYPES OF HEPATITIS

HEPATITIS A

Hepatitis A is also known as infectious hepatitis. It is common in older children and young adults. It is primarily transmitted by fecal- oral, person-to-person contact, and by uncooked shellfish, fruits, vegetables, and contaminated water. Pre-exposure prophylaxis includes either immungolobulin (IG) or Hepatitis A series of injections given before exposure. This is recommended for travelers to certain international countries. Travelers going to developing countries should avoid drinking the water and avoid uncooked shellfish, fruits, and vegetables.

HEPATITIS B

Hepatitis B is also known as serum hepatitis. Hepatitis B is transmitted via blood or body fluids at birth or during early childhood, through sexual contact and by contaminated needles. Healthcare workers would be at risk for this disease when in direct contact with blood, sustaining a contaminated needlestick injury or by a cut with a blood covered sharp object. A needlestick injury presents the greatest risk for infection with Hepatitis B if the source blood is infected with the virus. (6 to 30%) About 50 to 60% of infected persons do not know that they are infected with this virus, thus reporting this virus is very important. Hepatitis B presents the greatest risk for occupational illness. Taking a Hepatitis B vaccine can prevent this disease. There are two vaccines available to prevent this disease, Recombivax and Engerix HB. Both have proved safety and efficacy.  There is also a combination vaccine for hepatitis A and B available for adults, TwinRix.


HEPATITIS C

Hepatitis C is also known as non-A, non-B Hepatitis. Hepatitis C is transmitted in the same manner as Hepatitis B and is considered to be as serious. People at risk of acquiring Hepatitis C include transfusion recipients, IV drug users, and dialysis patients. Hepatitis C accounts for 20 to 40 percent of acute viral hepatitis in the United States.

HEPATITIS D

Hepatitis D is also known as the Delta – agent hepatitis. This type of hepatitis may cause infection only in the presence of active HBV (Hepatitis B) infection. Hepatitis D virus is a defective virus that needs a part of the HBV to complete its life cycle. The Hepatitis D virus is transmitted by routes similar to those of Hepatitis B. There have been reported cases of Hepatitis D in the United States. Individuals who are susceptible to Hepatitis B infection are also susceptible to Hepatitis D. Successful vaccination against Hepatitis B should also prevent Hepatitis D.

HEPATITIS E

Hepatitis E was first identified through waterborne epidemics in developing countries. Sporadic cases of Hepatitis E have been reported in the United States, but it is a problem in the Middle East. Hepatitis E is a mild disease except in women in the third trimester of pregnancy in which the mortality rate is high. Neither a carrier state nor a chronic live disease has been reported with this disease.

HEPATITIS G

Hepatitis G is the most recently described viral hepatitis. It was first recognized in 1995. To date, very little information is available about this virus or disease. It is thought that the route of transmission is through bloodborne spread.

HEPATITIS VACCINATION

If you are exposed to blood or other infectious material on a regular basis, the Hepatitis B vaccination is available. All students entering into the health sciences programs are required to have this vaccine. The vaccination is given in three intervals (initial dose, second dose one month following the first, and third dose six months following the first) and has proven to be ninety percent effective in preventing disease. Since 1992, OSHA has required employers to offer the Hepatitis B vaccine to all employees who are likely to have direct or indirect contact with blood and/or saliva. The vaccine is to be offered at no charge.

There are two recombinant Hepatitis B vaccines, which are FDA approved, Recombivax HB and Engerix-B. The vaccine is done in a series of three injections. Injections given in the deltoid muscle have produced seroconversions rates over 95% to 97% in immunocompetent, seronegative adults. Complete protection against HBV includes post-screening for antibody levels (a HBV titer). This procedure should be conducted one to two months after the final injection. All Dental Hygiene students will have a titer done at the completion of their hepatitis B series of injections. If a vaccine recipient fails to seroconvert, a second series of injections or a booster, as prescribed by a physician, should be given. After completion of the second series, another titer will be needed. Continued failure to respond should be investigated.

HIV/AIDS

AIDS (Acquire immune deficiency syndrome) is cause by HIV (Human Immunodeficiency Virus) and is a result of a weakened immune system. HIV attacks white blood cells and destroys the body’s ability to fight infection. The infections that strike people whose immune systems are weakened by HIV or other conditions include severe pneumonia and fungal infections of the mouth and esophagus. HIV infected people may also develop unusual cancers. Persons infected with HIV are considered to be communicable from the time of infection.

HIV cannot be spread through casual contact and is transmitted primarily by sexual contact- male-to-male, male to female, and in few cases female to male. HIV is known to be transmitted only through exposure to infected blood, semen, vaginal secretions, or breast milk. Being exposed to blood through use of soiled equipment, supplies, blood splashed on mucous membranes or broken skin can transmit HIV. It can be transmitted through sharing of IV drug needles and syringes and in smaller numbers by occupational exposure (needle stick injury) or through blood transfusion.

Symptoms of AIDS

Less severe symptoms
• Weakness
• Fever
• Shortness of breath
• Swollen lymph nodes
• Sore throat
• Headaches
• Chronic diarrhea
• Severe fatigue
• Night sweats
• Unexplained weight loss
• Discolored areas of the skin

Severe symptoms
• Mental disorientation- dementia
• Muscle wasting/ weakness- myelopathy
• Peripheral nerve numbness- neuropathy
• Persistent diarrhea
• Weight loss of more than ten percent of body weight

EXPOSURE CONTROL PLANS

An Exposure Control Plan is an important step in removing or reducing employee exposure to blood and other possibly infectious materials. The exposure control plan is a written plan of a company’s policies and procedures for handling blood and body fluids. The plan must be made available to employees at all times.

Midlands Technical College’s Exposure Control Plan can be found at the following locations:
• Chair of Health Sciences
• Student Affairs
• Personnel
• Allied Health & Nursing
• Operations

The Exposure Control Plan must contain:
• Identification of whom is covered.
• Rules of the engineering controls used.
• The work practice controls that are in use.
• Personal protection devices.
• A housekeeping schedule.
• Procedures for maintaining medical and training records.
• A list of tasks that can result in exposure and a list of the staff according to exposure category.
• A schedule and method of compliance for each part of the plan.
• The procedure for evaluating exposure incidents.

Exposure Determination

Each employer shall list tasks and procedures that have the potential to cause occupational exposure. The list is divided into groups or categories as follows:


• Category I
Includes those tasks in which employees performing the tasks have occupational exposure. These employees can expect contact with blood, body fluids, or tissues.

• Category II
Includes those tasks in which employees performing the tasks occasionally have occupational exposure. These employees normally have no contact with blood, body fluids, or tissues. However, these employees sometimes perform Category I tasks.

• Category III
Includes those tasks in which employees do not have occupational exposure. These employees have no exposure to blood, body fluids, or tissues.


ENGINEERING CONTROLS

Engineering controls are devices that isolate or remove the hazard from the workplace. They are the procedures that you use to do your job. Engineering controls include such things as puncture-resistant containers for sharp equipment and mechanical needle recapping device. To ensure that they work well, engineering controls should be examined, maintained or replaced on a regular basis.

SOME REQUIRED ENGINEERING CONTROLS ARE:
• Hand washing facilities that are readily accessible to employees.
• When hand-washing facilities are not feasible, the employer must provide appropriate antiseptic
  hand cleaner and clean cloth or paper towels.
• Provide puncture resistant sharps containers.

WORK PRACTICE CONTROLS


Work practice controls reduce the likelihood of exposure by changing the way a task is performed. The protection provided by work practice controls is based on the way an employer and employee behave rather than on a physical device.

Your personal hygiene habits, such as frequent handwashing, are as important in preventing infection as any equipment you might use. Some of required work practice controls are:

• Wash hands or other skin with soap and water as soon as feasible.
• Flush mucous membranes with water as soon as possible.
• Do not bend or recap needles.
• Eating, drinking, smoking, applying cosmetics or lip balm and handling contact lenses are
   prohibited in work areas.
• Do not store food and drinks with blood and body fluids. (hospital and labs)
• Decontaminate equipment that has become contaminated as necessary.
• Remove contaminated clothing as soon as possible.
• Do not wear contaminated clothing home.

GENERAL PERSONAL HYGIENE
Infection control begins with personal hygiene. The general rules for personal hygiene in health care settings are:

• Never touch anything that you don’t need to touch in performing your task. If your job requires you to treat patients and handle contaminated objects, touching other surfaces and materials causes contamination of these objects.
• Keep your hands off your body. Don’t rub your eyes, scratch your nose, or put your fingers in your mouth.
• Don’t eat, drink, smoke, apply cosmetics or lip balms, or handle contact lenses in the work areas.
• Do not wear jewelry. Rings can tear gloves. Earrings can become contaminated if not covered and necklaces get in the way.
• Do not store food in areas where lab specimens are kept.
• Keep hair away from your face. Use disposable head covers during surgical procedures or anytime you think your hair could enter the operating field or become splattered with blood.
• Keep your fingernails clean and short.
• If you have open or weeping sores, refrain from all direct patient contact until the lesions heal.
• Male healthcare workers- scrub your face thoroughly before shaving. Keep your beards and mustaches covered with a suitable mask.
• When working with blood or other potentially infectious materials, minimize splashing, spraying, splattering, and aerosols. Never pipette any material by mouth.
• Wash your hands. Infection control begins with hand washing. Wash your hands a minimum of 15 seconds at the beginning and end of each day. The soap must be in contact with your skin for this long  if it is to be effective. Iodophors and liquid hand cleaners containing PCMX, chlorhexidine gluconate, and triclosan are excellent for washing your hands.

PERSONAL PROTECTION EQUIPMENT

Personal protective equipment includes all equipment and supplies that keep you from direct contact with infected materials. These items act as a barrier between infectious substances and potential routes of entry. Protective equipment includes disposable gloves, gowns, masks and shields, eyewear and resuscitation devises.

The following guidelines should be followed when using protective equipment:

GLOVES
• Should be worn in any situation in which there is potential hand contact with blood, body fluids, mucous membranes or contaminated items. Disposable gloves are most commonly used.
• Check the gloves for holes, tears, or punctures before wearing.
• When removing potentially contaminated gloves, rollup the end of the glove inside out. This gives you a clean surface to remove the second glove with an unprotected hand.
• Wash hands immediately after removing gloves.
• Never wash or decontaminate disposable gloves for reuse.
• Hypoallergenic gloves are available if you are allergic to the gloves normally provided.
• Use heavy-duty (nitrile/vinyl) utility gloves to clean and disinfect the operatory and to scrub dirty instruments prior to sterilization.

PERSONAL APPAREL

• Gowns, aprons, and lab coats prevent infectious materials from reaching your clothing. In extreme situations, these gowns must be leak proof.
• Garments that become penetrated by blood or other potentially infectious materials must be removed immediately or as soon as possible and placed in an appropriately designated area or container for storage, washing, decontamination or disposal.
• Each day, newly laundered garments must be worn.
• Jewelry, including rings, bracelets, earrings, and necklaces, should not be worn in clinic areas.

PROTECTIVE EYE WEAR

• Protective eyewear is required for procedures that produce splashes, spray, spatter, droplets of blood, or aerosols.
• Protective eye wear (goggles or glasses with side shields) must be worn whenever contamination of the face can be reasonable anticipated.
• Chin-length face shields may be worn instead of goggles as long as the shield completely covers prescription glasses and wraps around far enough to protect the sides of the face and eyes from foreign material.
• A face shield is no substitute for a mask.

FACE MASKS

• OSHA prohibits working without a mask, even when wearing a shield. Aerosols can be sucked beneath and around the shield and into a worker’s respiratory system.
• Masks must cover the nose and mouth and block the inhalation of 95% of particles 3 to 5 microns in size.
• Masks must fit properly.
• Discard the mask between patients or whenever they become damp.
• Never wear a mask around your neck or on top of your forehead.

RESUSCITATION BAGS

• Use resuscitation masks or airway devices whenever you are performing artificial respiration.
• Resuscitation bags or pocket respirators with one way valves are recommended for emergency responders to protect against fluids that may be present in a resuscitation emergency.

HOUSEKEEPING

The standard requires a written plan for cleaning, identifying the method of decontamination based on the location within the facility, type of surface to be cleaned, type of soil and present procedures being performed in the area. A written schedule must ensure that work sites and equipment are clean and sanitary. The plan should also include a list of employees responsible for containment and disposition of a spill.

Some general rules to follow when cleaning are:
• Always wear gloves when cleaning.
• Clean up spills immediately or as soon as possible.
• If the spill is mixed with sharp objects, (such as glass) use a broom and dustpan to clean it up.
• Dispose of all contaminated items in a biohazard bag.
• Flood the area with disinfected solution of 1 part Clorox to 10 parts water, and allow it to stand for at least 20 minutes.

SHARPS

The greatest threat of exposure to bloodborne pathogens in the work place comes from a puncture to the skin from contaminated sharp objects.
When handling sharps, follow these guidelines:
• Use mechanical means such as broom and dustpan or tongs for picking up potentially contaminated sharp objects from the floor.
• Sharp containers must be used for the disposal of potentially contaminated sharp objects.
• Sharps containers are color coded with the Bio-safety red-orange and are puncture resistant and leak proof.
• When recapping needles, use a needle- recapping divice or the one-handed scoop technique.
• Gloves do not offer complete protection from being punctured by a sharp object. Janitorial or housekeeping personnel should use caution when handling linen or trash because of possible improper disposal of sharps.

SPILLS
Spills of blood or other potentially infectious material must be cleaned up immediately to prevent further contamination of the area. Follow these guidelines:

• Only the designated personnel should handle spills.
• Proper personal protective equipment should be worn.
• All materials used in the cleanup must be properly decontaminated and disposed.
• A 1 – 10 ratio of sodium hypochlorite (bleach) to water effectively kills any virus contained in blood.
• All absorbent material and disposable protective equipment used in the cleanup must be properly disposed of in bio-safety bags.

POST EXPOSURE EVALUATION AND FOLLOW UP

Despite being careful, accidents with potentially infectious materials can occur. An exposure incident is a specific eye, mouth, or other mucus membrane, non-intact skin or contact with blood or other potentially infectious body fluid. It is important to know what to do in case of emergency. If you suspect that you have be exposed to an infectious disease, the first steps that should be taken are:

• Wash any areas of contact with soap and water as quickly as possible.
• Contain material using absorbent barriers.
• Dispose of contaminated materials in approved waste containers.
• Notify your supervisor and safety/ Health department.
• Complete an incident report.

A number of steps will be taken for you if you are involved in an exposure incident:
• Your employer will provide a written description of the incident, routes of exposure and identity of the source individual to the health care professional.
• Your blood will be tested for infection.
• An appointment will be arranged with a health care professional to discuss the results of your blood test and recommend any appropriate treatment.
• The June 14, 1994 State law 44-29-230 states that the source individual can be tested against their will if there is an occupational exposure.
• The health care profession will provide your employer with an evaluation of the results of your test and their treatment for you.
• All information from your medical evaluation will remain confidential.

TRAINING

As soon as employees are assigned to Category I or Category II (see exposure determination), they must take part in a training program, provided at no cost during working hours. The program must train employees to assess, prevent, and control infectious and communicable diseases. The program must be repeated annually, and additional training must be offered when a change in procedures affects occupational exposure.

RECORDKEEPING REQUIREMENTS FOR TRAINING

Annual training must be provided to all employees who are covered by the regulation. Employees must receive this training before they are assigned to tasks where occupational exposure can occur.

Documentation of training should include:


The standard requires employers to establish and maintain records for all employees.

• The dates of the training session.
• The contents and summary of the session.
• The names and qualifications of the persons conducting the training.
• Names and job titles of all persons attending.
• The training records must be kept for 3 years from the date on which the training occurred.

MEDICAL RECORDS

Medical records must be kept on every employee with occupational exposure. The records must include the name and social security number of the employee, a copy of the employee’s hepatitis B vaccination status, as well as a copy of any exposure and follow up forms. The medical records are to be kept confidential. They are not to be disclosed without the employees written consent.


For credit in completing the orientation you must complete the following test. Use a Scantron answer sheet and return your test and CD to the infection control Coordinator. Thank you.
 

     The Post Test:

1.The goal of infection control is to _____________ by breaking the chain of infection.

a. protect health workers
b. protect patients
c. sterilize all operating rooms
d. prevent disease transmission

2. The biggest threat of disease in health facilities comes from

a. blood borne pathogens
b. air borne pathogens
c. water borne pathogens
d. all of the above

3. OSHA requires that all health workers be offered the ________ vaccination at no cost to the worker.

a. rubella
b. hepatitis B
c. influenza
d. all of the above

4. Soap must contact your hands for___________ if hand washing is to be effective.

a. 15 seconds
b. 30 seconds
c. 1 minute
d. 2 minutes

5.Should your skin or mucous membranes contact a patient’s blood,______.

a. call 911
b. wash immediately
c. continue procedures as if nothing occurred
d. all the above

6.Protective garments that become penetrated by blood must be _______.

a. changed immediately
b. incinerated
c. reported to OSHA
d. washed at home

7.Eye wear is required for procedures that produce ________.

a. droplets
b. aerosols
c. splashes, spray and spatter
d. all the above

8. Gloves must be worn if it can be reasonably expected that you will

a. contact blood
b. contact mucous membranes
c. handle contaminated items
d. all the above

9. Universal precautions are required because _________.

a. some infectious diseases have window phases
b. some patients do not know they have diseases
c. some patients do not disclose infectious diseases on their history forms
d. all the above


10. To recap needles safely, use _______.

a. a recapping device
b. the one handed scoop technique
c. both are acceptable
d. it is never acceptable to recap needles

11. Potentially infectious materials covered under standard precautions include _________.

a. blood, saliva, body fluids
b. tears, urine, vomitus
c. objects that touch infectious patients
d. all the above

12. The greatest threat to exposure to bloodborne pathogens in the work place comes from _________.

a. bacterial aerosols
b. assisting in surgery
c. wearing inappropriate personal protective equipment
d. puncture to the skin from a contaminated sharp object

13. Non-infectious materials include:

a. tears, sweat
b. sputum, urine, feces
c. vomitus and nasal secretions
d. all of the above

14. Using the Exposure Determination Plan, a dental hygienist would fall into:

a. Category I
b. Category II
c. Category III

15. Face masks should be changed:

a. after each patient
b. when they become damp
c. before lunch and at the end of the day
d. after each patient or when they become damp

16. Personal hygiene requires that you ___________.

a. keep fingernails short and clean
b. refrain from direct patient care if you have open sores.
c. cover mustaches with a mask
d. all of the above

17. Recommended hand soaps contain __________.

a. triclosan
b. PCMX
c. Chlorhexidine gluconate
d. All the above

18. Required protective equipment provided to employees includes ________.

a. gloves
b. eye protection
c. gowns
d. all the above

19. Training of all employees classified as Category I or Category II under the exposure determination plan must provide training to assess, prevent, and control infectious and communicable diseases every:

a. 6 months
b. year
c. 2 years
d. 5 years

20. OSHA’s Bloodborne Pathogen Standard applies to all ________exposures to blood or other potentially infectious materials.

a. occupational
b. parenteral
c. mucosal
d. parenteral and mucosal
 


Print this page and bring it with you to the Health Sciences Orientation.
Name:_______________
Date: _______________

Infection Control for Dental Hygiene Students
Answer Sheet

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