Cold and flu are common health issues. All of us have experienced the sore throat, runny nose, aching, and general sense of misery that announce the onset of the common cold. Other familiar signals include a cough, headache, and dry, sore, or sensitive breathing passages. In a given year, nearly half of the United States population will catch a cold and 40% will develop influenza, or the flu.
The symptoms of both the common cold and the flu are often the same, because both are caused by the same family of respiratory viruses. The distinction between the two depends on how severe the infection is and the range of symptoms. The flu is usually more severe, develops quickly, and involves more of the body than a cold. A cold also occurs at any time of year, while the flu usually develops in epidemics, normally in late fall and winter.
Beyond respiratory inflammation, the flu produces a moderate to high fever, aching muscles, and acute fatigue. Vomiting and diarrhea may also develop and, in extreme cases, the flu may lead to pneumonia in particularly susceptible individuals. Other complications of the flu, although rare, include inflammation of the brain (encephalitis) or heart (myocarditis), Reye’s syndrome (an illness primarily affecting children, involving abnormal brain and liver function), and croup.
As the body attempts to fight the invading pathogens that can cause colds and flu, white blood cells are rapidly transported to the sites of infection. The chemically mediated inflammatory response of white blood cells causes swelling, which can result in stuffed sinuses and swollen nose or throat. Mucus is also secreted to trap the pathogens. Such reactions are signs of a normally functioning immune system, as are a runny nose, sneezing, and coughing, which serve to expel toxins and infectious organisms in the form of phlegm.
Enhancing the body’s ability to remove phlegm is a central feature of the alternative medicine approach to treating colds and flu. In contrast, conventional medicine’s approach of suppressing symptoms with drugs can compromise immune function. As a result, though symptom relief may be achieved, the duration of colds and flu can often be prolonged. In addition, the use of antibiotics for secondary infections resulting from colds and flu, such as bronchitis, can disturb bowel function and further weaken the body, making it susceptible to more serious forms of illness.