Infection control principles and practices for local health agencies
TB - Preventing transmission
Mycobacterium tuberculosis is transmitted in airborne particles called droplet nuclei that are expelled when persons with pulmonary or laryngeal TB cough, sneeze, shout, or sing. The tiny infectious particles can be carried by air currents throughout a room or building. Tuberculosis is not transmitted by direct contact or via contaminated surfaces or items.
Local health agency personnel are potentially exposed to TB during case management activities such as directly observed therapy or when persons with unrecognized pulmonary TB are present in the agency facility. Local health agencies should establish TB infection control programs that include administrative and respiratory protection measures to help prevent TB transmission among staff and visitors. Environmental engineering of air handling systems to create airborne infection isolation rooms is used to house hospital TB patients but is usually not available in public health settings.
Administrative measures include assigning a designated staff person responsibility for TB infection control, conducting a TB risk assessment for the facility, writing a control plan, and implementing effective work practices for detecting and managing clients entering the facility with signs and symptoms that may indicate active TB disease.
Respiratory protection measures that include use of N-95 respirators are also necessary for public health personnel with exposure to active TB cases. A respiratory protection program should be established to provide staff training, fit-testing, and medical evaluation for respirator use.
The following general practices should be in place in all local health agency settings.
Basic measures to prevent transmission of TB in local health agencies
- Establish policies that minimize or eliminate the presence of suspect or known TB cases in local health agency facilities.
- Establish cough etiquette practices among staff and clients. Provide tissue, hand hygiene products, and waste containers in common areas such as waiting rooms so persons with respiratory symptoms can contain coughing and sneezing. Have surgical masks available for persons to wear while waiting, and place persons with respiratory symptoms in an examination room or area away from others as soon as possible. Display posters and other educational material to encourage cough etiquette practices. Consider use of barriers such as Plexiglas sneeze guards for reception areas.
- Implement a TB screening protocol for clients presenting with cough or other respiratory symptoms. A screening tool should determine the presence of any one of the following: duration of cough for more than three weeks, blood in sputum, night sweats, unexplained weight loss, and history of TB disease or TB exposure.
- If screening results increase suspicion of TB, ask the client to wear a surgical mask and place in a private examination room or remove from others immediately. All staff members entering the examination room should wear a NIOSH approved fit-tested N-95 respirator. Once the room is empty, it should remain unoccupied for a period of time to clear the air of airborne TB particles (see Table 1 in the CDC Guidelines for Preventing Transmission of TB for required times).
- Do not perform aerosol inducing procedures or sputum collections in public health facilities, as negative pressure room are usually not available to contain airborne particles generated by these procedures.
- Staff doing home visits for infectious TB patients should wear NIOSH approved fit-tested N-95 filtering face pieces or powered air-purifying respirators while in the shared air space of the patient.
Frequently Asked Questions (TB)
Infection control principles and practices for local health agencies
Local health agency employees usually do not see cases of suspected or known TB in their facilities. However, if someone who states he/she has TB presents to a LHD for services, how should staff manage that person?
The person should be asked to don a surgical mask immediately and be escorted out of the facility for referral to a health care facility able to provide appropriate infection control measures for TB patients. If the client is not able to leave right away, he/she should be taken to a private room until arrangements for departure can be made. Staff entering the private room should wear respiratory protection (NIOSH approved fit-tested N95 filtering face piece or PAPR). The client may remove the mask once he or she is outdoors.
Once the room is empty, it should remain unoccupied with the door closed for a period of time to allow the air to clear of infectious particles. The CDC Guidelines for Preventing Transmission of TB (table 1 (link is external)) (Exit DHS) specifies the amount of clearance time required based on the number of air exchanges that occur in the room per hour .
Contact your building maintenance staff if you do not already know the air exchange rate of the room.
Frequently Asked Questions (Respiratory Protection)
What is a PAPR, and how do I clean it?
A PAPR is a powered, air-purifying respirator. It is a battery operated device that draws air through a filter to remove very small infectious agents such as TB bacteria. The air then flows into a hood that covers the wearer’s head and face, and in this way the user is able to breathe air that has only minimum or no infectious agents. PAPRs should be cleaned according to manufacturer’s instructions to avoid damage to the units.
Who can perform a medical evaluation?
The OSHA respiratory protection standard states that a physician or other licensed health care professional must perform the medical evaluation. This refers to an individual whose legal scope of practice (that is holding a license, registration, or certification) allows him or her to independently provide a medical evaluation. If the evaluation questionnaire reveals a medical condition requiring further evaluation, the employee should be referred to a physician (MD or DO in Wisconsin) or practitioner whose scope of practice legally allows them this action. Generally further evaluation is done by nurses, physician assistants, or other licensed health professionals working under MD or DO orders.
How often do medical evaluations need to be completed?
An initial medical evaluation must be completed before the employee can wear a respirator and periodically thereafter as determined by the physician or other licensed health professional In addition an evaluation must be completed:
if an employee reports signs and symptoms related to the ability to wear a respirator.
if the medical advisor or respiratory protection program administrator requires it
if observations made during fit testing indicate the need for a medical evaluation
if changes in the workplace conditions occur that may result in increased physical burdens to the employee.
Can an agency contract out for services related to respiratory protection?
Yes, but an in-house, on-site program administrator must also be present. Agencies can use other companies to provide fit testing, medical evaluation, and other components of the respiratory protection program. Any contracting company should be carefully evaluated before enlisting their services.
What types of respiratory protection devices require fit-testing?
All respirators that fit tightly on the face must be fit-tested (e.g. N-95 filtering face pieces, PAPRs with half or full face pieces). Those with loose-fitting face pieces do not need to be fit- tested.
How often must fit-testing occur?
Fit-testing must occur before an employee first uses a respirator, at least annually thereafter, before a different make or model of respirator is used, or when there are changes in an employees physical condition that may affect the fit of the respirator (e.g. significant weight changes, changes in facial features).
Do I need to be certified or have any other training to do fit-testing?
Persons do not need to be certified or have specific qualifications in order to perform fit-testing. They should, however, receive training and become proficient in fit-testing procedures.
Who can administer a respiratory protection program?
Although no specific requirements are listed in the OSHA Respiratory Protection Standard, an employer should designate someone who is qualified by appropriate training or experience to manage the complexity of the program.
How often do employees under a respiratory protection program need to receive training?
Training must occur before initial use of respiratory protection and at least annually thereafter, when changes in the workplace render previous training obsolete, or when inadequacies in an employee’s knowledge or use of the respirator indicate the employee has not retained the information or skills from the previous training.
What records must be kept in a respiratory protection program?
Employers must keep records of medical evaluations and fit-testing procedures. Medical evaluations are part of the employee’s medical record and as such must be kept for the period of employment plus 30 years. Information on access to employee exposure and medical records OSHA Standard 29 CFR 1910.1020
I have a staff member who refuses to shave his beard. What should I do?
OSHA does not allow employees to wear tight-fitting respirators if they have facial hair that comes between the sealing surface of the face piece and the face or if the hair interferes with valve function. So employees must either shave if they need to wear a tight-fitting respirator or they can use a loose fitting PAPR, which does not require fit-testing.
- Preventing Transmission of Mycobacterium tuberculosis in Health-Care Settings - CDC Guidelines, 2005
- Respiratory Hygiene/Cough Etiquette in Healthcare Settings - CDC
- Respiratory Protection Standard - OSHA
- Wisconsin Tuberculosis Program
- TB infection control plans
- Respiratory protection plan model for local public health
Gwen Borlaug, Infection Control Epidemiologist
Wisconsin Division of Public Health
Bureau of Communicable Diseases