| disease | Acute Upper Respiratory Infection |
| alias | Common Cold, Upper Respiratory Infection, Common Cold, Common Cold |
Acute upper respiratory tract infection refers to the general term for acute inflammation of the nasal cavity, pharynx, or larynx. It is one of the most common pestilence diseases of the respiratory tract. The common disease causes are viruses, with a few caused by bacteria. Patients can be of any age, gender, occupation, or region. It not only has strong pestilence characteristics but can also lead to serious complications, so active prevention and treatment are essential.
bubble_chart Epidemiology
This disease can occur throughout the year, with a higher incidence in winter and spring. It can be transmitted through virus-containing droplets or contaminated utensils. Most cases are sporadic, but outbreaks often occur during sudden climate changes. Due to the variety of virus types, the immunity produced by the human body after infection with various viruses is weak and short-lived, and there is no cross-immunity. Additionally, there are virus carriers among healthy individuals, so a person can experience multiple episodes of the disease within a year.
Acute upper respiratory infections are caused by viruses in about 70-80% of cases. The main viruses include influenza viruses (types A, B, and C), parainfluenza virus, respiratory syncytial virus, adenovirus, nasal diseases virus, echovirus, coxsackievirus, measles virus, and rubella virus. Bacterial infections can occur directly or following viral infections, with hemolytic streptococcus being the most common, followed by Haemophilus influenzae, pneumococcus, and staphylococcus. Occasionally, gram-negative bacilli are seen. The main manifestations of these infections are rhinitis, pharyngitis, or tonsillitis.
When predisposing factors such as catching a cold, getting wet in the rain, or excessive fatigue reduce the body's overall or local respiratory defense mechanisms, viruses or bacteria that already exist in the upper respiratory tract or invade from the outside can rapidly multiply, leading to illness. This is especially true for the elderly, young children, or those with chronic respiratory diseases such as sinusitis or tonsillitis, who are more susceptible to infection.
bubble_chart Pathological Changes
The nasal and pharyngeal mucosa are congested and edematous, with epithelial cell damage and a small number of mononuclear cell infiltrations, accompanied by serous and mucous inflammatory exudates. Following secondary bacterial infection, there is infiltration of neutrophils and a large amount of purulent discharge.bubble_chart Clinical Manifestations
Depending on the different disease causes, clinical manifestations can vary in type:
I. Common Cold (Common Cold)
Commonly known as "common cold," also referred to as acute rhinitis or upper respiratory catarrh, it primarily presents with catarrhal symptoms in the nasopharynx. In adults, it is mostly caused by nasal diseases viruses, followed by parainfluenza virus, respiratory syncytial virus, echovirus, and coxsackievirus. The onset is relatively acute, with the initial stage [first stage] featuring dry throat, throat itchiness, or a burning sensation. At the same time or a few hours after the onset, symptoms such as sneezing, stuffy nose, and clear nasal discharge may occur, which thickens after 2-3 days. It may be accompanied by sore throat, sometimes with hearing loss due to eustachian tube inflammation, and may also present with tearing, dull taste, difficulty breathing, hoarseness, and a slight cough. Generally, there is no fever or systemic symptoms, or only low-grade fever, malaise, grade I fear of cold, and headache. Examination may reveal nasal mucosal congestion, edema, and secretions, with grade I pharyngeal congestion. If there are no complications, recovery usually occurs within 5-7 days.
II. Viral Pharyngitis, Laryngitis, and Bronchitis
Depending on the inflammatory response caused by viruses infecting different anatomical parts of the upper and lower respiratory tracts, clinical manifestations can include pharyngitis, laryngitis, and bronchitis.
Acute sexually transmitted disease viral pharyngitis is mostly caused by nasal diseases viruses, adenovirus, influenza virus, parainfluenza virus, enterovirus, and respiratory syncytial virus. Clinical features include throat itchiness and a burning sensation, with pain that is not persistent or prominent. Pain during swallowing often indicates streptococcal infection. Cough is rare. Fever and lack of strength may occur with influenza virus and adenovirus infections. Physical examination shows significant pharyngeal congestion and edema. Submandibular lymph nodes are swollen and tender. Adenovirus pharyngitis may be accompanied by conjunctival membrane inflammation.
Acute sexually transmitted disease viral laryngitis is mostly caused by nasal diseases viruses, influenza A virus, parainfluenza virus, and adenovirus. Clinical features include hoarseness, difficulty speaking, pain during coughing, often with fever, pharyngitis, or cough. Physical examination reveals laryngeal edema, congestion, local lymph node grade I swelling and tenderness, and wheezing sounds may be heard.Acute sexually transmitted disease viral bronchitis is mostly caused by respiratory syncytial virus, influenza virus, coronavirus, parainfluenza virus, nasal diseases virus, and adenovirus. Clinical manifestations include cough, with no sputum or mucus-like sputum, accompanied by fever and lack of strength. Other symptoms often include hoarseness and non-membrane chest pain below the sternum. Dry or wet rales may be heard. Chest X-ray shows increased and enhanced vascular shadows but no lung infiltration shadows. Acute bronchitis caused by influenza virus or coronavirus often occurs during acute exacerbations of chronic bronchitis.
III. Herpangina
Often caused by coxsackievirus A, it presents with significant sore throat and fever, with a course of about one week. Examination shows pharyngeal congestion, with gray-white herpes and superficial ulcers on the soft palate, uvula, pharynx, and tonsil surfaces, surrounded by redness. It mostly occurs in summer, commonly in children, and occasionally in adults.
IV. Pharyngoconjunctival Fever
Mainly caused by adenovirus and coxsackievirus. Clinical manifestations include fever, sore throat, photophobia, tearing, and significant congestion of the pharynx and conjunctival membrane. The course lasts 4-6 days, often occurring in summer and spread through swimming. It is more common in children.
V. Bacterial Pharyngitis-Tonsillitis
Mostly caused by hemolytic streptococcus, followed by Haemophilus influenzae, pneumococcus, and staphylococcus. The onset is acute, with significant sore throat, fear of cold, and fever, with body temperature potentially exceeding 39°C. Examination shows significant pharyngeal congestion, swollen and congested tonsils with yellow spotty exudates, swollen and tender submandibular lymph nodes, and no abnormal signs in the lungs.
bubble_chart Auxiliary Examination1. Blood Picture
In viral infections, the white blood cell count is normal or low, with an increased proportion of lymphocytes. Bacterial infections are characterized by an increased white blood cell count, neutrophilia, and a left shift.
2. Determination of Viruses and Viral Antigens
As needed, methods such as immunofluorescence, enzyme-linked immunosorbent assay (ELISA), serological diagnosis, and virus isolation and identification can be used to determine the type of virus and differentiate between viral and bacterial infections. Bacterial culture is used to determine the type of bacteria and conduct drug sensitivity tests.
Based on medical history, epidemiological context, symptoms and signs of nasopharyngeal inflammation, combined with peripheral blood tests and chest X-ray examinations, a clinical diagnosis can be made. Bacterial culture and virus isolation, or virological serological tests, immunofluorescence assays, enzyme-linked immunosorbent assays (ELISA), and hemagglutination inhibition tests can be used to determine the disease cause.
bubble_chart Treatment Measures
There are currently no specific antiviral drugs for respiratory viruses, and symptomatic or Chinese medicine treatment is commonly used.
1. Symptomatic Treatment
Patients with severe conditions, fever, or those who are elderly and weak should rest in bed, avoid smoking, drink plenty of water, and ensure indoor air circulation. For fever and headache, antipyretic and analgesic tablets such as compound formula aspirin or pain relief tablets can be taken orally. For sore throat, anti-inflammatory throat lozenges can be used, and local nebulization treatment can be applied. For stuffy nose and runny nose, 1% Ephedrine nasal drops can be used.
2. Antibacterial Drug Treatment
If there is a bacterial infection, appropriate antibiotics such as penicillin, erythromycin, spiramycin, or ofloxacin can be selected. Generally, antibiotics are not needed for simple viral infections.
Chemotherapy for viral infections is not yet mature. Moroxydine (ABOB) has some efficacy against influenza and respiratory viruses. Vidarabine has some effect on adenovirus infections. Rifampin can selectively inhibit viral RNA polymerase and has some efficacy against influenza and adenoviruses. In recent years, a synthetic and potent interferon inducer—polyinosinic-polycytidylic acid (poly I:C)—has been discovered, which can induce the production of interferon in the human body and inhibit viral replication.
3. Chinese Medicine Treatment
The use of Chinese patent drugs or the principle of pattern identification and treatment has unique advantages for upper respiratory tract infections.
Enhancing the body's own disease resistance is the best way to prevent acute upper respiratory infections. This includes adhering to regular and appropriate physical exercise, persisting with cold water baths to improve the body's ability to prevent diseases and adapt to cold, ensuring proper cold protection to avoid triggers of illness, maintaining a regular lifestyle, avoiding overwork especially excessive work at night, and paying attention to the isolation of respiratory patients to prevent cross-infection.
Acute sinusitis, otitis media, and tracheobronchitis may occur concurrently. Some patients may develop Bi disease, glomerulonephritis, myocarditis, and other conditions.
1. Allergic Rhinitis
Clinically resembles the "common cold," but differs in its sudden onset, nasal itching, frequent sneezing, and clear nasal discharge. The episodes are related to sudden changes in the environment or temperature, and can sometimes be triggered by unusual odors. Recovery occurs within a few minutes to 1-2 hours. Examination: The nasal mucosa appears pale and edematous, and a smear of nasal secretions shows an increase in eosinophils.
2. Epidemic Common Cold
Often has a clear epidemic pattern. The onset is sudden, with severe systemic symptoms such as high fever, body aches, and significant conjunctival inflammation, but milder nasopharyngeal symptoms. A smear of mucosal epithelial cells from the patient's nasal wash, stained with fluorescent-labeled influenza virus immune serum and examined under a fluorescence microscope, aids in early diagnosis. Viral isolation or serological diagnosis can also be used for differentiation.
3. Acute Pestilence Prodromal Symptoms
Diseases such as measles, poliomyelitis, and encephalitis often present with upper respiratory symptoms in their early stages. During the epidemic season or in epidemic areas, close observation and necessary laboratory tests should be conducted to differentiate these conditions.