The virus most often implicated in causing the common cold may be responsible for only half the cases of cold symptoms, according to researchers in Finland.
In the February issue of the Journal of Clinical Microbiology, researchers at the National Public Health Institute of Finland reported on a study of 200 cases of cold symptoms that university students experienced during a 1-year period. The researchers identified an infectious agent as the cause of 138 of the 200 cases. But rhinovirus, often considered the cause of colds, was present in only 105 of the cases. Coronavirus, influenza A virus, and respiratory syncytial virus also were identified as the cause of symptoms. Seven students had bacterial infections, and 6 had coinfections with viral and bacterial agents.
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