The flu is an infectious disease, caused by a virus. It presents with fever, muscle and joint pain, nasal congestion, and headache.The flu has a high contagiousness, coupled with the virus’ ability to mutate from one season to the next. In the most frail groups, such as the elderly and patients with chronic conditions, such as COPD, heart disease, and diabetes, influenza can have serious complications.
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Risk factors, complications, and prevention of ankylosing spondylitis
The risk factors for ankylosing spondylitis (AS) can be various, starting with a fragile vertebral structure or the presence of persistent rheumatic diseases.