What is the web of causation?
The model of web of causation shows that diseases are not distributed randomly in any group but isolation of how they are distributed requires one to study several factors. This implies that there are multiple and heterogeneous causes of any disease, symptom or health condition, collectively forming a web of causation.
What is the causal organism of tuberculosis?
Tuberculosis (TB) is caused by a bacterium called Mycobacterium tuberculosis. The bacteria usually attack the lungs, but TB bacteria can attack any part of the body such as the kidney, spine, and brain.
What is the epidemiological triad of tuberculosis?
The main factors predisposing to TB acquisition follow the causal model of the epidemiological triad, which shows that the interaction among the bacillus, the host and environmental factors increases the probability of catching TB(1).
What are the two causative organisms of tuberculosis?
tuberculosis and M. bovis are the most common causative agents of TBLN.
What is tuberculosis epidemiology?
Introduction to TB Epidemiology. TB infection is one of the most common infections in the world. It is estimated that nearly 2 billion people (about one fourth of the world’s population) are infected with M. tuberculosis. Every year, about 10 million people develop TB disease and 1.6 million people die of it.
What is the epidemiology of M. tuberculosis?
Most cases are estimated to be in Asia and Africa (58% and 27% respectively), with the highest incidence in India (range 2.0–2.4 million) and China (0.9 −1.1 million), together accounting for 38% of the total number of cases.
Which is an example of a web of causation?
For example, a web of causation model for a person who contracted measles would include things like places where the person may have contracted this disease, whether or not the person has received a measles vaccine and any health factors that make the person prone to contracting measles, such as an immune deficiency disease.
How does tuberculosis spread from person to person?
Tuberculosis is caused by bacteria that spread through the air, just like a cold or the flu. When someone who has it coughs, sneezes, talks, laughs, or sings, tiny droplets that contain the germs are released. If you breathe in these germs, you can get it.
What makes tuberculosis such a dangerous killer infection?
Another reason tuberculosis remains a major killer is the increase in drug-resistant strains of the bacterium. Since the first antibiotics were used to fight tuberculosis more than 60 years ago, some TB germs have developed the ability to survive, and that ability gets passed on to their descendants.
Why did tuberculosis become more common in developed countries?
Once rare in developed countries, tuberculosis infections began increasing in 1985, partly because of the emergence of HIV, the virus that causes AIDS. HIV weakens a person’s immune system so it can’t fight the TB germs.