prevention of mycobateria tuberculosis in healthcare settings
TRANSCRIPT
PREVENTION OF MYCOBACTERIUM TUBERCULOSIS IN HEALTHCARE SETTINGS
Dr. Moustapha A.Ramadan
Introduction
The mycobacteria are acid-fast rod-shaped bacteria. They are usually slow-growing.
There are many different kinds, the most common one causes tuberculosis and leprosy.
Still others cause infections that are called atypical mycobacterial infections, because they don't cause tuberculosis and can still harm people with low immunity status.
Introduction
The mycobacteria includes:
Mycobacterium tuberculosis -- which causes tuberculosis
Mycobacterium leprae -- which causes leprosy
Mycobacterium ulcerans -- which causes Buruli ulcer
Introduction
The mycobacteria includes:
Mycobacterium avium -- which causes tuberculosis -like illness in birds and immunodeficient people;
Mycobacterium marinum – which causes swimming pool granuloma;
Mycobacterium abscessus – which causes cystic fibrosis and skin lesions
Facts
In 2013, 9 million people fell ill with TB and 1.5 million died from the disease
Globally in 2013, an estimated 480 000 people developed multidrug resistant TB (MDR-TB).
In 2013, an estimated 550 000 children became ill with TB and 80 000 HIV-negative children died of TB.
Facts
About one-third of the world's population has latent TB.
TB is a leading killer of HIV-positive people causing one fourth of all HIV-related deaths.
The TB death rate dropped 45% between 1990 and 2013
Facts
TB is spread from person to person through the air. When people with lung TB cough, sneeze or spit, they propel the TB germs into the air.
The symptoms may be mild for many months.
People ill with TB can infect up to 10-15 other people through close contact over the course of a year
Symptoms
a bad cough that lasts 3 weeks or longer coughing up blood or sputum pain in the chest weakness or fatigue weight loss, loss of appetite chills, fever sweating at night
Multidrug-resistant tuberculosis (MDR-TB) is a form of TB caused by bacteria that do not respond to, at least, isoniazid and rifampicin, the two most powerful anti-TB drugs.
The primary cause of MDR-TB is inappropriate treatment, inappropriate or incorrect use of anti-TB drugs, or use of poor quality medicines.
PREVENTION & CONTROL
Preventing transmission of M.tuberculosis
I. Administrative MeasuresII. Environmental ControlIII. Respiratory Protection
Administrative Measures
The first and most important level of TB controls is the use of administrative measures to reduce the risk for exposure to persons who might have TB disease.
Setting Assessment
Conduct periodic reassessments (annually, if possible) to ensure:
proper implementation of the TB infection control plan
prompt detection and evaluation of suspected TB cases
prompt initiation of airborne precautions of suspected infectious TB cases
Setting Assessment
Conduct periodic reassessments (annually, if possible) to ensure:
recommended medical management of patients with suspected or confirmed TB disease
functional environmental controls
implementations of the respiratory protection program
ongoing HCW training and education regarding TB.
Processing and Reporting of lab results
It is essential that sputum collection and delivery to the laboratory be done in a timely manner, and results should be available within 24 hours of specimen collection.
Processing and Reporting of lab results
The laboratory performing acid fast bacilli (AFB) smears should be proficient at:
Methods of sputum specimen processing
The administrative aspects of specimen processing (e.g., record keeping, notification)
Maintaining quality control of diagnostic procedures (e.g., AFB sputum smears)
Ensuring adequate supplies for processing sputum samples.
Managing patients with suspected or confirmed TB disease
A high index of suspicion for TB disease and rapid implementation of precautions are essential to prevent and interrupt transmission.
Managing patients with suspected or confirmed TB disease
I. Prompt triage/ Proper history taking:
1) a history of TB exposure, infection, or disease;
2) symptoms or signs of TB disease;
3) medical conditions that increase their risk for TB disease.
Managing patients with suspected or confirmed TB disease
II. TB airborne precautions
1. should be initiated for any patient who has symptoms or signs of TB disease.
2. has documented infectious TB disease and has not completed anti-tuberculosis treatment.
3. patients who have confirmed TB disease or who are considered highly probable to have TB disease, promptly start anti-tuberculosis treatment
Managing patients with suspected or confirmed TB disease
II. TB airborne precautions discontinuation (suspected)
another diagnosis is made that explains the clinical syndrome
the patient has three consecutive, negative AFB sputum smear results
Managing patients with suspected or confirmed TB disease
II. TB airborne precautions discontinuation (confirmed)
have received appropriate anti-tuberculosis chemotherapy directly observed for a minimum of two weeks
and have shown clinical improvement
Managing patients with suspected or confirmed TB disease
II. TB airborne precautions discontinuation (confirmed)
In setting known to have high prevalence of MDR-TB sputum smear negative should be added to the previous criteria
Cleaning, disinfection, sterilization of patient care equipment and rooms
The same cleaning procedures used in other rooms in the health-care setting should be used to clean AII rooms.
Personnel should follow airborne precautions while cleaning these rooms when they are still in use.
Cleaning, disinfection, sterilization of patient care equipment and rooms
Critical Medical Instruments should be sterile at the time of use.
Semi-critical Medical Instruments is preferred to be sterile however, high-level disinfection that destroy vegetative microorganisms is accepted
Non-critical Medical Instruments or devices cleaning and disinfection
Training and Education of HCWs
HCW training and education can increase adherence to TB infection-control measures.
Training and education should emphasize the increased risks posed by an undiagnosed person with TB disease in health-care setting and the specific measures to reduce this risk.
Training and Education of HCWs
Follow-up TB Training and Education is based
on the number of untrained and new HCWs,
changes in the organization and services of the setting,
availability of new TB infection control information.
HCW surveillance
Baseline testing for M. tuberculosis infection is recommended for all newly hired HCWs, regardless of the risk classification of the setting
Any HCW with a newly recognized positive test result for M. tuberculosis infection, test conversion, or symptoms or signs of TB disease should be promptly evaluated.
HCW surveillance
Such HCWs should be excluded from the workplace and should be allowed to return to work when the following criteria have been met:
Three consecutive sputum samples collected in 8–24-hour intervals that are negative, with at least one sample from an early morning specimen;
The person has responded to antituberculosis treatment that will probably be effective
HCW surveillance
Such HCWs should be excluded from the workplace and should be allowed to return to work when the following criteria have been met:
The person is determined to be noninfectious by a physician experienced in managing TB disease.
HCWs with extra pulmonary TB disease usually do not need to be excluded from the workplace as long as no involvement of the respiratory tract has occurred.
Patient Education
Patients should be educated about M.tuberculosis transmission and the importance of cough etiquette. Posters emphasizing cough etiquette should be placed in the waiting areas.
Environmental Controls
The second level of the hierarchy is the use of environmental controls to prevent the spread and reduce the concentration of infectious droplet nuclei in ambient air.
By law, the local health department must be notified when TB disease is suspected or confirmed in a patient or HCW so that follow up can be arranged and a community contact investigation can be conducted.
Environmental Controls
Primary environmental controls consist of controlling the source of infection by using local exhaust ventilation (e.g., hoods, tents, or booths) and diluting and removing contami nated air by using general ventilation.
Secondary environmental controls consist of controlling the airflow to prevent contamination of air in areas adjacent to the source (AII rooms) and cleaning the air by using high efficiency particulate air (HEPA) filtration
AII Room Practices
AII rooms should be single bed and has a private bathroom.
Keep doors to AII rooms closed except when patients, HCWs, or others must enter or exit the room.
Monitor and record direction of airflow (i.e., negative pressure) in the room on a daily basis, while the room is being used for TB airborne precautions.
AII Room Practices
Perform diagnostic and treatment procedures (e.g., sputum collection and inhalation therapy) in an AII room.
Ensure that patients with suspected or confirmed infectious TB disease who must be transported to another area bypass the waiting area and wear a surgical mask
AII Room Practices
Schedule procedures on patients with TB disease when a minimum number of HCWs and other patients are present and as the last procedure of the day to maximize the time available for removal of airborne contamination.
Maintenance of environmental control measures
Ensure the optimal selection, installation, operation, and maintenance of environmental controls.
Personnel should schedule routine preventive maintenance for all components of the ventilation systems (e.g., fans, filters, ducts, supply diffusers, and exhaust grills) and air-cleaning devices.
Respiratory Protection
The third level of the hierarchy is the use of respiratory protective equipment in situations that pose a high risk for exposure .
training HCWs on respiratory protection, and training patients on respiratory hygiene and cough etiquette procedures
Respiratory Protection
All persons, including HCWs and visitors, entering rooms in which patients with suspected or confirmed infectious TB disease are being isolated;
Persons present during cough-inducing or aerosol generating procedures performed on patients with suspected or confirmed infectious TB disease;
Laboratorians conducting aerosol-producing procedures might require respiratory protection.
Respiratory Protection
Persons who transport patients with suspected or confirmed infectious TB disease in vehicles (e.g., EMS vehicles or, ideally, ambulances) and persons who provide urgent surgical or dental care to patients with suspected or confirmed infectious TB disease.
Respiratory Protection
Disposable respirators (e.g., N-95s) are commonly used in TB isolation rooms, in transport of TB cases, or in other areas of the health care facility.
Full face piece negative-pressure respirators, powered air-purifying respirators (PAPRs) is required when high-risk procedures such as bronchoscopy or autopsy are conducted.