Air that farmers breathe is contaminated with toxic gases or particulate matter that is dangerous. Continuous exposure to these contaminants leads to the condition called farmer’s lung.
Farmer’s lung is a hypersensitivity allergy reaction that is caused by breathing in dust from moldy hay, grain handling, feed handling and livestock confinement systems or other agricultural products.
The hypersensitive inflammatory response in farmer’s lung can become a chronic condition that is dangerous. Initially disease starts as sudden attack or slow progressive disease and it causes breathing problems. Avoiding the exposure to dust and moldy crops is beneficial but long term exposure causes permanent damage to lung causing physical disability or even death.
The degree of risk depends on how much amount is collected in person’s lungs. Working with loose hay in open field is less dangerous while working indoors a farmer inhales large amount of dust within a short period of time.Age/sex prevalence of Farmer's lung
Acute farmer’s lung starts as an acute attack within 4-8 hours when a person breathes a large amount of dust from moldy crop.
Signs and symptoms subside after 12 hours of avoiding the exposure to moldy dust but it can last up to 2 weeks. Severe attack can last as long as 12 weeks.
• Sub-acute farmer’s lung:
Sub acute farmer’s lung is more common as compared to acute farmer’s lung. Sub acute farmer’s lung is more difficult to notice as it is less intense. It develops slowly from continual exposure to small amount of hay. Sub acute farmer’s lung mimics common chest cold and remains throughout winters. Some people lose weight over several weeks.
• Chronic farmer’s lung:
Chronic farmer’s lung develops slowly over a period of year after several acute attacks. Persons who are in continuous exposure to moldy dust are at great risk.
When a person inhales a large amount of dust and spores, the immune system produces antibodies against that antigen. Once the antibodies are produced a person becomes sensitive to that allergen. On further exposure to moldy dust generates a hypersensitive type of allergic reaction.
The signs and symptoms of sub acute farmer’s lung:
– Muscle and joint pain.
– Shortness of breath.
– General sick feeling.
– Loss of appetite and weight.
Signs and symptoms of chronic farmer’s lung include:
– Shortness of breath.
– Occasional mild fever.
– Lack of energy.
– Marked loss of weight.
– Permanent lung damage.