FAQs: What should you do in case of exposure to bloodborne pathogens and aerosols?
This information is adapted from the Centers for Disease Control and Prevention website
What constitutes an occupational exposure in dentistry?
An exposure can be defined as a percutaneous injury (e.g., needlestick or cut with a sharp object) or contact of mucous membrane or non-intact skin (e.g., exposed skin that is chapped, abraded, or with dermatitis) with blood, saliva, tissue, or other body fluids that are potentially infectious. Exposure incidents might place dental health care personnel at risk for hepatitis B virus (HBV), hepatitis C virus (HCV), or human immunodeficiency virus (HIV) infection, and therefore should be evaluated immediately following treatment of the exposure site by a qualified health care professional.
What body fluids are potentially infectious during an occupational exposure?
When evaluating occupational exposures to fluids that might contain hepatitis B virus (HBV), hepatitis C virus (HCV), or human immunodeficiency virus (HIV), health care workers should consider that all blood, body fluids, secretions, and excretions except sweat, may contain transmissible infectious agents. Blood contains the greatest proportion of infectious bloodborne virus particle titers of all body fluids and is the most critical transmission vehicle in the health-care setting. During dental procedures it is predictable that saliva will become contaminated with blood. If blood is not visible, it is still likely that very small quantities of blood are present, but the risk for transmitting HBV, HCV, or HIV is extremely small. Despite this small transmission risk, a qualified health care professional1 should evaluate any occupational exposure to saliva in dental settings, regardless of visible blood.
What is the risk of infection after an occupational exposure?
Hepatitis B Virus (HBV)
Health care workers who have received hepatitis B vaccine and have developed immunity to the virus are at virtually no risk for infection. For an unvaccinated person, the risk from a single needlestick or a cut exposure to HBV-infected blood ranges from 6%–30% and depends on the hepatitis B e antigen (HBeAg) status of the source individual. Individuals who are both hepatitis B surface antigen (HBsAg) positive and HBeAg positive have more virus in their blood and are more likely to transmit HBV.
Hepatitis C Virus (HCV)
Based on limited studies, the estimated risk for infection after a needlestick or cut exposure to HCV-infected blood is approximately 1.8%. The risk following a blood splash is unknown but is believed to be very small; however, HCV infection from such an exposure has been reported.
Human Immunodeficiency Virus (HIV)
- The average risk for HIV infection after a needlestick or cut exposure to HlV-infected blood is 0.3% (about 1 in 300). Stated another way, 99.7% of needlestick/cut exposures to HIV-contaminated blood do not lead to infection.
- The risk after exposure of the eye, nose, or mouth to HIV-infected blood is estimated to be, on average, 0.1% (1 in 1,000).
- The risk after exposure of the skin to HlV-infected blood is estimated to be less than 0.1%. A small amount of blood on intact skin probably poses no risk at all. There have been no documented cases of HIV transmission due to an exposure involving a small amount of blood on intact skin (a few drops of blood on skin for a short period of time). The risk may be higher if the skin is damaged (for example, by a recent cut), if the contact involves a large area of skin, or if the contact is prolonged.
What should be done following an occupational exposure? (Oral healthcare providers should check their provincial standards to ensure there are no additional registries they should contact following a significant exposure in their offices).
Post-exposure Protocol: all oral healthcare workers should know their Hepatitis B immunization status and serology results (antibodies are equal to or greater than 10 IU/litre).
- Stop the procedure immediately
- Inform the patient that an injury has occurred to the operator (as the patient may think that they have been injured or that treatment has been compromised).
- Remove gloves and wash hands
- Injuries to the skin should be washed well with copious amounts of running water. Free bleeding of puncture wounds should be encouraged, however, there is no documented evidence to support that squeezing the wound will further reduce the risk of transmission of bloodborne infection. The site of exposure should be washed well with soap and water (not necessarily antibacterial soap) but without scrubbing. Antiseptics, bleach, and skin washes should not be used. Mucous membranes are flushed well with water. When splashes have occurred to the eye, the eye-wash station is to be used to thoroughly to flush the eyes.
- Ensure that the injury is a Significant Exposure.
- Provide first aid if required. Determine if the operator can stop the procedure or temporize the treatment.
- Patients are asked to submit to blood testing and a risk assessment – generally at a local emergency center or hospital where the staff routinely assess significant exposures for hospital staff. A Confidential Incident Report will be completed stating the date and time of the exposure, circumstances of the incident, nature and extent of injury, action taken at time of injury, the name of the exposed, name of the source, and known bloodborne status of the source.
- With their permission, patients should be transported to an acute care setting or emergency setting for blood work. The affected worker should have a blood test performed to demonstrate baseline status.
- The administered post-exposure prophylaxis (PEP) is most efficacious if it is administered within 4 hours following the exposure.
- Confidential Incident Report will be completed stating the date and time of the exposure, circumstances of the incident, nature and extent of injury, action taken at time of injury, the name of the exposed, name of the source, and known bloodborne status of the source.
- Include a notation in the daily treatment record of the chart describing the incident and the patient’s reaction to the exposure.
What factors must qualified health care professionals consider when assessing the need for follow-up of occupational exposures?
The evaluation must include the following factors to determine the need for further follow-up:
Type of exposure
- Percutaneous injury (e.g., depth, extent)
- Mucous membrane exposure
- Nonintact skin exposure
- Bites resulting in blood exposure to either person involved
- Type and amount of fluid/tissue
Blood
- Fluids containing blood
Infectious status of source
- Presence of hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg)
- Presence of hepatitis C virus (HCV) antibody
- Presence of human immunodeficiency virus (HIV) antibody
Susceptibility of exposed person
- Hepatitis B vaccine and vaccine response status
- HBV, HCV, or HIV immune status
After conducting this initial evaluation of the occupational exposure, a qualified health care professional must decide whether to conduct further follow-up on an individual basis using all of the information obtained.
What are some measures to reduce the risk of blood contact?
Avoiding occupational exposures to blood is the primary way to prevent transmission of HBV, HCV, and HIV in health care settings. Methods used to reduce such exposures in dental settings include engineering and work practice controls and the use of personal protective equipment (PPE).
Engineering controls isolate or remove the bloodborne pathogens hazard from the workplace. These controls are frequently technology-based and often incorporate safer designs of instruments and devices. Examples include sharps disposal containers, rubber dams, and self-sheathing anesthetic needles. Whenever possible, engineering controls should be used as the primary method to reduce exposures to bloodborne pathogens following skin penetration with sharp instruments or needles.
Work practice controls are behavior-based and are intended to reduce the risk of blood exposure by changing the manner in which a task is performed. Examples include using the “scoop” technique to recap an anesthetic needle, removing burs before placing the hand piece in the dental unit, and restricting the use of fingers during suturing and when administering anesthesia.
Personal protective equipment consists of specialized clothing or equipment worn to protect against hazards. Examples include gloves, masks, protective eyewear with side shields, and gowns to prevent skin and mucous membrane exposures.
CDC website accessed on March 19, 2014
Should dentists be convened about exposure to human papilloma virus?
On behalf of Dr. Nita Mazurat:
HPV is a sexually transmitted disease with a strong association between oropharyngeal cancer and HPV.
Two excellent resources for dentists are: Center for Disease Control (CDC) http://www.cdc.gov/hpv/ specifically, http://www.cdc.gov/std/hpv/stdFact-HPVandoralcancer.htm and the Organization for Safety, Asepsis, and Prevention (OSAP) website (search HPV).
What do you mean by point #4 Ensure that the injury is a Significant Exposure? How do you determine this, and how is management changed based on the “significance” of the exposure?
On behalf of Dr. Nita Mazurat:
The term “Significant Exposure” is a term used mostly in Canada to identify occupational injuries associated with percutaneous or mucosal injuries with increased risk for transmission of bloodborne diseases. You may be more familiar with the term “sharps injuries” or ‘mucosal injuries’ (mostly to the eyes) with resultant need for the source to be asked to submit to blood testing. If the instrument causing injury has been contaminated with blood and there has been sufficient blood transmitted from the source to the exposed person then a cascade of events are triggered including a request of the source person for blood testing to determine their status for blood borne diseases including HBV, HCV, and mostly, HIV. The need for post-exposure prophylaxis will depend on the results of a risk assessment of the patient as well as the results of the blood testing. It is standard of practice in Canada to have oral healthcare workers vaccinated and tested for response to vaccine to protect against Hepatitis B, particularly since there is immunization available and the risk of transmission for Hepatitis B is approximately 30%. Unfortunately there are no vaccines available at this time to protect against Hepatitis C or HIV.
Many injuries occur that are not “significant”, that is, where there is no body fluid involved or where there is insufficient blood or blood in body fluid to result in transmission. Although it is difficult to quantify “sufficient”, I have heard it described as being a ‘drop’ which is also difficult to quantify in a clinical environment. If the exposed healthcare worker feels anxious about the injury, the source should be asked to be transported to a hospital setting for blood testing and the worker should have a baseline blood test done at that time. Post-exposure prophylaxis is most efficacious if started within 2 hours of the exposure.
An injury from a contaminated needle is always considered a Significant Exposure whereas a very minor injury where there is no or only minor bleeding is considered a ‘near miss’ or an ‘incident’. All injuries should be documented to determine if there is a pattern of practices that should be reassessed.
Post-exposure protocol should be part of an Office Infection Control policy, clearly documented in an office Infection and Prevention Control Manual including directions to the nearest hospital.