Pulmonary Tuberculosis (TB) Lung Disease Pulmonary Tuberculosis (TB)

Background Usually found in the lungs as transmitted via droplets in the air. Infectious disease that is the biggest killer – approx 2 million people per year die from it. Previously known as consumption. Pre-WW2 campaign.

Causes Rod shaped bacteria Myobacterium tuberculosis Myobacterium bovis 30% world’s population have one form in their blood stream.

Symptoms Persistent cough Tiredness Loss of appetite leading to weight loss Fever Coughing up of blood droplets

Transmission Through the air by droplets by sneezing, coughing, laughing esp in crowded places or friends/relatives Resistant bacterium, can survive many weeks M bovis infects cattle and can contaminate milk Risk Groups Living and sleeping in overcrowded conditions Work or live in long-term care facilities People from countries where TB is prevalent Reduced immunity (children/HIV patients/elderly/alcoholics/homeless/transplant patients/malnourished)

Course of infection Early infection Primary Infection (occurs in children) Post-Primary infection (many years later – adults) Can be FATAL Bacteria grow and divide in upper regions of the lungs Inflammation and enlargement of lymph nodes Bacteria re-emerge to cause a 2nd TB infection Phagocytes accumulate at these sites to ingest bacteria Bacteria destroy lung tissue resulting in cavities and scar tissue. Healthy person will control infection in a few weeks but a few bacteria remain Coughs up lung tissue, blood and bacteria, can spread to rest of the body.

Prevention and Control of TB Vaccination of those without immunity – weak strain of M bovis Better education Better housing Improved health facilities Better nutrition Drug treatment (6-9 months)

Why has there been an increase of TB recently in developed countries?