Study: NCT04126304

Intervention type: DRUG
Intervention: Azithromycin
Description: If the diagnosis is common cold, acute bronchitis or post-infection cough ，treated with non-macrolides when the mycoplasma colloidal gold test is negative, treated with azithromycin when colloidal gold test is positive.

Intervention type: DRUG
Intervention: Azithromycin
Description: If the diagnosis is common cold, acute bronchitis or post-infection cough ，treated with non-macrolides when the mycoplasma colloidal gold test is negative, treated with azithromycin when colloidal gold test is positive.

Intervention type: DRUG
Intervention: Azithromycin
Description: If the diagnosis is common cold, acute bronchitis or post-infection cough ，treated with non-macrolides when the mycoplasma colloidal gold test is negative, treated with azithromycin when colloidal gold test is positive.

Intervention type: DRUG
Intervention: non-macrolides antibiotics
Description: If the diagnosis is community-acquired pneumonia with negative mycoplasma antibody-granule agglutination, non-macrolides are used for treatment

Intervention type: DIAGNOSTIC_TEST
Intervention: Mycoplasma detection
Description: 1. common cold, acute bronchitis or post-infection cough :MPlgM colloidal gold detection;Pharyngeal swab MP-RNA PCR, mutated gene detection at 2063 and 2064 site of macrolide-resistant 23S rRNA II region detection~2. community-acquired pneumonia:mycoplasma antigen antibody particle agglutination detection ;Sputum MP-RNA PCR, mutated gene detection at 2063 and 2064 site of macrolide-resistant 23S rRNA II region detection

Intervention type: DIAGNOSTIC_TEST
Intervention: Mycoplasma detection
Description: 1. common cold, acute bronchitis or post-infection cough :MPlgM colloidal gold detection;Pharyngeal swab MP-RNA PCR, mutated gene detection at 2063 and 2064 site of macrolide-resistant 23S rRNA II region detection~2. community-acquired pneumonia:mycoplasma antigen antibody particle agglutination detection ;Sputum MP-RNA PCR, mutated gene detection at 2063 and 2064 site of macrolide-resistant 23S rRNA II region detection

Intervention type: DIAGNOSTIC_TEST
Intervention: Mycoplasma detection
Description: 1. common cold, acute bronchitis or post-infection cough :MPlgM colloidal gold detection;Pharyngeal swab MP-RNA PCR, mutated gene detection at 2063 and 2064 site of macrolide-resistant 23S rRNA II region detection~2. community-acquired pneumonia:mycoplasma antigen antibody particle agglutination detection ;Sputum MP-RNA PCR, mutated gene detection at 2063 and 2064 site of macrolide-resistant 23S rRNA II region detection

Intervention type: DIAGNOSTIC_TEST
Intervention: Mycoplasma detection
Description: 1. common cold, acute bronchitis or post-infection cough :MPlgM colloidal gold detection;Pharyngeal swab MP-RNA PCR, mutated gene detection at 2063 and 2064 site of macrolide-resistant 23S rRNA II region detection~2. community-acquired pneumonia:mycoplasma antigen antibody particle agglutination detection ;Sputum MP-RNA PCR, mutated gene detection at 2063 and 2064 site of macrolide-resistant 23S rRNA II region detection

Intervention type: OTHER
Intervention: Data collection
Description: 1. Common cold:On enrollment, day 3 and day 7, scores were collected based on the Canadian acute respiratory diseases and influenza scale (CARIFS scale), success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.~2. Acute bronchitis :on enrollment, day 3, and day 7, the Likert 7 subscale was used to score the cough severity questionnaire, collect the success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.~3. Post-infection cough:on the day after outpatient visit, day 3, day 7, and day 14, the cough severity questionnaire (Likert 7 subscale) was used to score the success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.

Intervention type: OTHER
Intervention: Data collection
Description: 1. Common cold:On enrollment, day 3 and day 7, scores were collected based on the Canadian acute respiratory diseases and influenza scale (CARIFS scale), success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.~2. Acute bronchitis :on enrollment, day 3, and day 7, the Likert 7 subscale was used to score the cough severity questionnaire, collect the success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.~3. Post-infection cough:on the day after outpatient visit, day 3, day 7, and day 14, the cough severity questionnaire (Likert 7 subscale) was used to score the success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.

Intervention type: OTHER
Intervention: Data collection
Description: 1. Common cold:On enrollment, day 3 and day 7, scores were collected based on the Canadian acute respiratory diseases and influenza scale (CARIFS scale), success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.~2. Acute bronchitis :on enrollment, day 3, and day 7, the Likert 7 subscale was used to score the cough severity questionnaire, collect the success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.~3. Post-infection cough:on the day after outpatient visit, day 3, day 7, and day 14, the cough severity questionnaire (Likert 7 subscale) was used to score the success rate of initial treatment, antimicrobial conversion rate, intravenous rehydration rate, pneumonia conversion rate, re-visit rate, and hospitalization rate.

Intervention type: OTHER
Intervention: Data collection
Description: Acquisition of children hospitalized time, heating time, mixed infection, drug (azithromycin, tetracycline, quinolone) dose and use time, pulmonary complication (pleural effusion, atelectasis, necrotizing pneumonia, interstitial pneumonia, occlusive bronchitis, occlusive bronchiolitis, lung, emphysema, lung abscess, bronchiectasis, transparent), pleural puncture/drainage, bronchoscope, oxygen time, into the ICU, mechanical ventilation time, surgery, and deaths and re-visit, hospitalization, surgery and death within 30 days after discharge