Mycobacterium Tuberculosis

Decline During ,377 cases of TB (5.8/100,000 of U.S. population) were reported to CDC 7% dec from 1999 39% dec from 1990 In 1992 there was a resurgence of TB in U.S. (due to AB resistance, immigration, travel, HIV+)

Population at highest risk – foreign born

Rate per Population Source: CDC

Mycobacterium Tuberculosis (TB) Slow growing bacteria that primarily affects the respiratory tract of humans. Other areas that can be affected:

TB Spreading What happens after the bacteria have entered the body?  Begins to grow in alveoli (small air sacs) of lungs and then spreads throughout lung and body via blood

5 Lung Anatomy 3 4 Source: CDC 1

Incubation What is usual TB incubation period?  2-10 weeks for TB infection  Up to 2 years for TB disease (highest risk) TB infected (Latent TB): (carrier)  Positive Skin Test, but not contagious (& no symptoms) TB disease/active:  + Skin test and showing symptoms (bad cough, fever, chills, blood in sputum) and is highly contagious

Testing  PPD (Purified Protein Derivative) – tuberculin injected intradermally & read 48 hours later

PPD Testing Source: CDC

Transmission Inhalation of infectious particles:  Infectious particles are carried in air after an active TB individual speaks, coughs, sneezes, or certain medical procedures are performed These particles are called droplet nuclei 1-5 microns/ 1/5000 of an inch in size

Infected Person Transmitting Droplets Inhalation of Droplets Cough-Sneeze-Talking

Respirator A PPE device that removes air contaminants such as dust, mists, and aerosols from ambient air TB Respirator filters out material down to 0.3 microns at 95% efficiency (N95).  NIOSH approved

TB Respirator Mask N 95 NIOSH Approved Must be fit tested (sized correctly)

TB (AFB) Isolation Acid Fast Bacilli (AFB) isolation room:  Warning signs  Must be maintained under negative pressure.  Exhaust air from isolation room away from air intakes for building, usually on roof.

Filters High Efficiency Particulate Air filter (HEPA):  Used to filter air for recirculation in an AFB isolation room at 0.3 microns at 99.97% efficiency

Settings at TB Risk High Risk Settings:  Health care settings  Correctional institutions  Homeless shelters  Long-term care facilities for the elderly  Drug treatment centers