Tuberculosis (TB) is a potentially fatal infectious disease caused by a bacterium called Mycobacterium tuberculosis (M. tuberculosis). The bacteria usually infect the lungs but can attack any part of the body including the kidney, spine, and brain; this is more common in young children or those with weakened immune systems. Most people infected with TB do not have symptoms (latent TB) but if they are not treated, about 10% will develop active disease. Nearly 10 million people have active disease worldwide and about 1.5 million will die from the infection, mostly in developing countries. Active infection in the lungs is characterized by a chronic cough with blood-tinged mucus, fever, night sweats, and weight loss. This highly contagious disease is spread through the air when a person with active pulmonary infection coughs, sneezes, spits, or speaks. Risk factors for developing TB include HIV, overcrowded conditions, malnutrition, chronic lung disease, smoke exposure, and exposure to immunosuppressant medications such as corticosteroids and anti-TNF antibodies. Antibiotics are used to treat latent and active TB infections, but therapy can take several months. Combinations of antibiotics are used to prevent resistance development, but multi-drug resistant strains are on the rise.
Vaccine research relies on the ability to properly expose test subjects to the M. tuberculosis strain. The use of head out plethysmographs, masks, or helmets from DSI enables the aerosol to be delivered simultaneously with the measurement of respiration rate and tidal volume. This helps create a reproducible and more accurate delivery method to the lungs.
References using head out plethysmograph solutions to study tuberculosis:
Sibley L, Dennis M, Sarfas C, White A, Clark S, Gleeson F, McIntyre A, Rayner E, Pearson G, Williams A, Marsh P, Sharpe S. “Route of delivery to the airway influences the distribution of pulmonary disease but not the outcome of Mycobacterium tuberculosis infection in rhesus macaques.” Tuberculosis. 2016;96:141-149.
Sharpe S, McShane H, Dennis M, Basaraba R, Gleeson F, Hall G, McIntyre A, Gooch K, Clark S, Beveridge N, Nuth E, White A, Marriott A, Dowall S, Hill A, Williams A, Marsh P. “Establishment of an Aerosol Challenge Model of Tuberculosis in Rhesus Macaques and an Evaluation of Endpoints for Vaccine Testing.”Clinical and Vaccine Immunology. 2010;17:1170-1182.