Tuberculosis

What Is It? Bacterial infectionBacterial infection Caused by Mycobacterium tuberculosis (also called tubercle bacillus)Caused by Mycobacterium tuberculosis (also called tubercle bacillus) Damages a persons lungs or other parts of the bodyDamages a persons lungs or other parts of the body Fatal if not treated properlyFatal if not treated properly

Transmission Spreads through the air when a person with active TBSpreads through the air when a person with active TB –Coughs –Speaks –Laughs –Sneezes –Sings –Another person breathes in the bacteria and becomes infected

Inside the Body Breath in infected air and bacilli go to lungs through bronchiolesBreath in infected air and bacilli go to lungs through bronchioles Bacilli infect alveoliBacilli infect alveoli Macrophages attack bacteria, but some surviveMacrophages attack bacteria, but some survive Infected macrophages separate and form tuberclesInfected macrophages separate and form tubercles Dead cells form granulomasDead cells form granulomas

Active vs. Latent Infection Unhealthy personUnhealthy person –Bacilli overwhelm immune system –Bacilli break out of tubercles in alveoli and spread through bloodstream –This is ≥active≤ TB Healthy personHealthy person –Initial infection controlled by immune system –Bacilli remain confined in tubercles for years –This is ≥latent≤ TB

Symptoms Perpetual CoughPerpetual Cough FeverFever Weight lossWeight loss Night sweatsNight sweats Loss of appetiteLoss of appetite FatigueFatigue Swollen glandsSwollen glands ChillsChills Pain while breathingPain while breathing

Diagnosis Skin test- Mantoux testSkin test- Mantoux test PPD injected in forearm and examined 2-3 days laterPPD injected in forearm and examined 2-3 days later Red welt around injection indicates infectionRed welt around injection indicates infection Examine medical history, x-rays, and sputumExamine medical history, x-rays, and sputum

Most Susceptible People at higher risk of TB infectionPeople at higher risk of TB infection –Close contacts with people with infectious TB –People born in areas where TB is common –People with poor access to health care –People who inject illicit drugs –People who live or work in residential facilities –Health care professionals –The elderly

Most Susceptible People at higher risk of active TB diseasePeople at higher risk of active TB disease –People with weak immune systems (especially those with HIV or AIDS) –People with diabetes or silicosis –People infected within the last 2 years –People with chest x-rays that show previous TB disease –Illicit drug and alcohol abusers

Treatments Take antibiotics for 6-12 monthsTake antibiotics for 6-12 months Preventative drug to destroy dormant bacteriaPreventative drug to destroy dormant bacteria For active TB, 4 medications: isoniazid, rifampin, ethambutol, and pyrazinamideFor active TB, 4 medications: isoniazid, rifampin, ethambutol, and pyrazinamide Vaccines (relatively ineffective today)Vaccines (relatively ineffective today)

Biological Effects on Humans Causes more deaths than any other infectious diseaseCauses more deaths than any other infectious disease About 2 billion people infected worldwideAbout 2 billion people infected worldwide Major health problem in developing countriesMajor health problem in developing countries Leading killer of youth and young adultsLeading killer of youth and young adults Leading cause of death for women of childbearing ageLeading cause of death for women of childbearing age