Chlamydia pneumoniae is a common species of bacteria of the Chlamydia genus. Approximately 50 percent of Americans aged 20 and older have experienced a Chlamydia pneumoniae infection, and reinfection later in life seems common, notes the Centers for Disease Control and Prevention. Most cases of Chlamydia pneumoniae infection cause no symptoms, or cause mild symptoms not recognized as an illness. In some cases the infection can cause a respiratory illness, sometimes with characteristic clinical manifestations and symptoms.
Cough and Fever
Cough symptoms, sometimes over a prolonged period, may signal a case of pneumonia or bronchitis due to a Chlamydia pneumoniae infection. Those illnesses constitute the most frequently recognized diseases connected with Chlamydia pneumoniae, notes Dr. Cho-Chou Kuo, in a 1995 review article in "Clinical Microbiology Review." Fever symptoms may accompany the cough. The symptoms may have a characteristically sub-acute onset, meaning that they begin fairly rapidly, but not abruptly. Dr. Chou notes that often, by the time a patient sees a doctor, the fever symptoms may have already resolved. The illnesses associated with Chlamydia pneumoniae infections are often mild, and people tend to wait longer before seeing a doctor after the onset of symptoms than they do with other acute respiratory infections.
Sore throat, one of the main symptoms of pharyngitis, may occur near the beginning of an illness caused by Chlamydia pneumoniae. Many viruses and several different bacteria can cause pharyngitis, an inflammation of the throat. When Chlamydia pneumoniae bacteria cause the infection, the infected person may also experience concurrent hoarseness. Dr. Chou points out that in those with Chlamydia pneumoniae infections, the onset of symptoms sometimes occurs in two phases, with pharyngitis symptoms in the early stages. Those symptoms often resolve before the beginning of pneumonia or bronchitis syndromes. Headache, another typical pharyngitis symptom, may accompany the sore throat symptoms.
A Chlamydia pneumoniae infection may cause a person to experience dyspnea, or labored breathing symptoms, according to Merck Manuals Online Medical Library. Chlamydia pneumoniae-associated bronchitis may cause a sensation of tightness in the chest and shortness of breath. Shortness of breath is also a symptom of pneumonia, along with chest pain that increases during inspiration or while coughing. Merck mentions tachypnea, an abnormally fast rate of breathing, and tachycardia, an abnormally fast heart rate as other symptoms of pneumonia. Nasal congestion symptoms, along with post-nasal drip, may affect those with sinusitis caused by Chlamydia pneumoniae.