Influenza is a respiratory tract infection producing symptoms mainly in the nose and throat. Infection usually lasts about a week, and the symptoms are present with rapid onset of fever, headache and generalized ache. Flu viruses are spread easily from person to person through coughing or sneezing. In the United States, influenza viruses are responsible for approximately 35,000 deaths and 200,000 hospitalizations each year, according to The American Journal of Medicine.
Cardiac Complications
In rare cases, the influenza virus A may evoke cardiac complications in persons regardless of age, notes the Experimental and Clinical Cardiology journal. Myocarditis, which is inflammation of the heart muscle, is a potentially life-threatening, long-term effect of influenza virus A. It is most prominent during epidemics of influenza. The spectrum of the presentations of cardiac complications is wide, ranging from mild myocarditis to cardiogenic shock.
Reye's Syndrome
Reye's syndrome is a fatal disease of the brain, known as encephalopathy, and is characterized by fever, vomiting and lethargy. The etiology of Reye's syndrome is unclear, but it appears to involve certain viral strains, including influenza, according to the University of South Carolina. Influenza viruses cause nonpermissive or abortive infections of the brain and liver. Fat deposits are seen diffusely all over the liver, which interfere with liver functions. Cerebral edema, or swelling, occurs in the brain.
Guillain-Barré Syndrome
Guillain-Barré syndrome is a neurological disorder that occurs when antibodies of the immune system mistakenly attack the body's own tissues, especially the peripheral nervous system. Guillain-Barré syndrome can accompany viral infections, such as influenza. Early symptoms of this disorder include tingling sensations in the legs, arms, chest and face. Over time, these symptoms slowly increase in severity until the patient completely becomes paralyzed, according to the National Institute of Neurological Disorders and Stroke.
References
- World Health Organization: Influenza
- The American Journal of Medicine: Complications of viral influenza
- University of South Carolina School of Medicine: Influenza Virus; Dr. Margaret Hunt
- PubMed Central: Experimental and Clinical Cardiology: Cardiac tamponade and heart failure as a presentation of influenza
- National Institute of Neurological Disorders and Stroke: NINDS Guillain-Barré Syndrome Information Page
