In March 2009, an outbreak of “human swine influenza” occurred in Mexico and spread rapidly around the world. The World Health Organization (WHO) initially called this type of influenza “human swine influenza”, and later renamed it “Influenza A (H1N1)” On June 11, WHO announced that it would raise the level of pandemic warning for Influenza A (H1N1) to level 6, and the world entered the pandemic phase. Influenza A (H1N1) is a new type of respiratory infection. This influenza is a new type of respiratory infectious disease, the pathogen of which is the new influenza A (H1N1) virus strain, which contains gene fragments of three influenza viruses, namely swine flu, avian influenza and human influenza. This diagnosis and treatment plan is revised on the basis of the second version of the diagnosis and treatment plan on July 10, based on the recent domestic and foreign research results and China’s experience in diagnosis and treatment of influenza A (H1N1). As this influenza A (H1N1) is a new disease, its disease pattern is still to be further observed and studied. First, the pathogenesis of influenza A H1N1 virus belongs to the orthomyxoviridae (0rthomyxoviridae), influenza A virus genus (Influenza virus A). Typical virus particles are spherical, 80nm-120nm in diameter, with a capsular membrane. There are many radially arranged protruding glycoproteins on the capsule membrane, which are erythrocyte hemagglutinin (HA), neuraminidase (NA), and matrix protein M2.The viral particles have a nucleocapsid within the capsid, which is helically symmetric and has a diameter of 10 nm.The virus is a single-stranded, negative-stranded RNA virus, with a genome of about 13.6 kb, consisting of 8 independent segments of varying sizes. The virus is sensitive to ethanol, povidone-iodine, tincture of iodine and other commonly used disinfectants; it is sensitive to heat, and can be inactivated in 30 minutes at 56℃. Second, epidemiology (a) source of infection. Influenza A (H1N1) patients as the main source of infection, asymptomatic infected people are also infectious. Currently there is no evidence of animal transmission to humans. (B) the transmission route. Mainly through droplet transmission through the respiratory tract, but also through the oral cavity, nasal cavity, eyes and other places of mucous membrane direct or indirect contact transmission. Contact with the patient’s respiratory secretions, body fluids and objects contaminated by the virus may also cause infection. Transmission through the respiratory tract via aerosols needs to be further confirmed. (iii) Susceptible population. The population is generally susceptible. (d) High-risk groups who are more likely to become seriously ill. The following groups of people with influenza-like symptoms are more likely to develop severe cases and should be given high priority for early detection of influenza A (H1N1) virus nucleic acid and other necessary tests. 1. Pregnant women; 2. People with the following diseases or conditions: chronic respiratory diseases, cardiovascular diseases (except hypertension), renal diseases, liver diseases, hematologic diseases, neurological and neuromuscular diseases, metabolic and endocrine system diseases, immune function suppression (including the application of immunosuppressive drugs or HIV infection, etc. leading to immunocompromised function), and people under the age of 19 years who are taking aspirin for a long time; 3, Obese people (high risk of body mass index ≥40, body mass index of 30-39 may be a high-risk factor); 4, children aged <5 years old (age <2 years old is more prone to serious complications); 5, elderly people aged ≥65 years old. Third, clinical manifestations and auxiliary examination The incubation period is usually 1-7 days, mostly 1-3 days. (A) clinical manifestations. Usually manifested as influenza-like symptoms, including fever, sore throat, runny nose, nasal congestion, cough, sputum, headache, generalized aches and pains, fatigue. Vomiting and/or diarrhea are present in some cases. A few cases have only mild upper respiratory symptoms without fever. Signs mainly include pharyngeal congestion and enlarged tonsils. Complications such as pneumonia may occur. In a few cases, the disease progresses rapidly, with respiratory failure, multiple organ insufficiency or failure. It may induce exacerbation of the original underlying disease and present the corresponding clinical manifestations. Severe cases can lead to death. （Laboratory tests. 1. Peripheral blood test: the total number of white blood cells is generally not high or low. 2.Blood biochemical examination: hypokalemia occurs in some cases, and creatine kinase, aspartate aminotransferase, alanine aminotransferase and lactate dehydrogenase are elevated in a few cases. (1) Viral nucleic acid test: RT-PCR (preferably using real-time RT-PCR) method to detect influenza A (H1N1) virus nucleic acid in respiratory specimens (pharyngeal swabs, nasal swabs, nasopharyngeal or tracheal aspirates, sputum), and the results can be positive. (2) Virus isolation: Influenza A (H1N1) virus can be isolated from respiratory specimens. (3) Serum antibody test: dynamic detection of double serum influenza A (H1N1) virus-specific antibody levels were 4 times or more elevated. (3) Chest imaging. When combined with pneumonia, flaky shadows can be seen in the lungs. Diagnosis Diagnosis is mainly combined with epidemiologic history, clinical manifestations and pathogenic examination, early detection and diagnosis is the key to prevention, control and effective treatment. (I) Suspected cases. Meet one of the following conditions can be diagnosed as a suspected case: 1, 7 days before the onset of influenza A (H1N1) with the infectious period of confirmed cases of influenza A close contact, and influenza-like clinical manifestations. Close contact means that in the absence of effective protection, diagnosis and treatment, care of infectious influenza A (H1N1) patients; living with the patient; contact with the patient's respiratory secretions, body fluids and so on. 2. Having traveled to an area with an influenza A (H1N1) epidemic (the emergence of sustained human-to-human transmission of the virus and community-based epidemics and outbreaks) within 7 days prior to the onset of the illness, and the emergence of influenza-like clinical manifestations. (3) The presence of influenza-like clinical manifestations and a positive test for influenza A virus, with no further testing for virus subtypes. For the above 3 cases, pathogenetic examination of influenza A (H1N1) may be arranged when conditions permit. (ii) Clinically diagnosed cases. Clinical diagnosis is limited to the following cases: in the same influenza A (H1N1) outbreak, cases with influenza-like symptoms that have not been confirmed by the laboratory can be diagnosed as clinically diagnosed cases when other influenza-like symptom-causing diseases are excluded. An influenza A (H1N1) outbreak is defined as a short period of time in which an abnormally high number of influenza-like illnesses occur in an area or unit and are confirmed by laboratory testing as an influenza A (H1N1) epidemic. Where conditions permit, clinically diagnosed cases may be scheduled for pathogenetic testing. (C) Confirmed cases. The appearance of influenza-like clinical manifestations, at the same time one or more of the following laboratory test results: 1, influenza A (H1N1) virus nucleic acid test positive (can be used real-time RT-PCR and RT-PCR methods); 2, the isolation of influenza A (H1N1) viruses; 3, double serum influenza A (H1N1) virus-specific antibody levels were four times or more than four times elevated. V. Serious and critical cases (a) the presence of one of the following conditions is a serious case: 1, persistent high fever > 3 days; 2, severe cough, coughing up pus sputum, bloody sputum, or chest pain; 3, rapid respiratory rate, respiratory distress, cyanosis of the lips; 4, altered mental state: unresponsive, lethargy, agitation, convulsions, etc.; 5, severe vomiting, diarrhea, and dehydration manifestations; 6, signs of pneumonia in the imaging examination; 7, Rapidly increasing levels of cardiac enzymes such as creatine kinase (CK) and creatine kinase isoenzyme (CK-MB); 8. Significant aggravation of the original underlying disease. (b) One of the following conditions is considered as critical cases: 1) respiratory failure; 2) infectious toxic shock; 3) multiple organ insufficiency; 4) other serious clinical conditions that require monitoring and treatment. VI. Clinical classification and treatment principles 1, suspected cases: isolated in a well-ventilated room. Hospitalized cases shall do the pathogenic examination of influenza A (H1N1). 2. Clinically diagnosed cases: isolated in a well-ventilated room. Hospitalized cases must undergo pathogenic examination for Influenza A (H1N1). 3.Confirmed cases: isolation in well ventilated rooms. Hospitalized cases can be more than one person in the same room. Principles of hospitalization According to the patient’s condition and local medical resources, hospitalization shall be arranged in accordance with the principle of giving priority to serious illnesses. 1. Prioritize the admission of serious and critical cases. For critical cases, according to the conditions of local medical facilities, timely transfer to the intensive care unit (ICU) with prevention and control conditions for treatment. 2, do not have serious and critical cases of medical institutions, under the premise of ensuring medical safety, we must promptly transfer cases to hospitals with conditions; the condition is not suitable for referral, the local health administrative departments or higher-level health administrative departments to organize experts on-site active treatment. 3, high-risk groups infected with influenza A (H1N1) is more likely to become a serious case, it is appropriate to arrange for hospitalization and treatment. If home isolation treatment is implemented, the condition should be closely monitored and hospitalization should be arranged in case of deterioration. Mild cases can be arranged for home isolation for observation and treatment. Treatment (A) General treatment. Rest, drink plenty of water, and closely observe changes in the condition; antipyretic treatment can be given to cases with high fever. (ii) Antiviral treatment. Studies have shown that the influenza A (H1N1) virus is sensitive to the neuraminidase inhibitors oseltamivir and zanamivir, and resistant to amantadine and amantadine ethylamine. Active use of neuraminidase inhibitors is not necessary in cases of influenza A (H1N1) with mild clinical symptoms and no comorbidities, and where the disease tends to be self-limiting. For cases with severe illness at the onset of illness and dynamic deterioration of illness after the onset of illness, antiviral treatment with neuraminidase inhibitors should be given promptly to people at high risk of influenza A (H1N1) infection. Initiation of administration should be within 48 hours of onset of illness if possible (within 36 hours is optimal). For high-risk groups that are more likely to become severe cases, antiviral therapy can be started as soon as influenza-like symptoms develop, without necessarily waiting for the results of viral nucleic acid testing. In pregnant women, it is advisable to give neuraminidase inhibitor therapy as soon as possible after the onset of influenza-like symptoms. Oseltamivir: Adult dosage is 75 mg b.i.d. for 5 days. In critically or severely ill cases, the dose of oseltamivir may be increased to 150 mg b.i.d. as appropriate. For prolonged cases, the dosage period can be extended appropriately. pediatric patients aged 1 year and above should be administered according to their body weight: 30 mg b.i.d. for those weighing less than 15 kg; 45 mg b.i.d. for those weighing 15-23 kg; 60 mg b.i.d. for those weighing 23-40 kg; and 75 mg b.i.d. for those weighing more than 40 kg. For children who have difficulty swallowing capsules, oseltamivir suspension may be used. Zanamivir: For adults and children over 7 years of age. The dosage for adults is 10mg inhalation b.i.d. for a 5-day course of treatment, and for children 7 years of age and older, the dosage is the same as for adults. (iii) Other treatments. 1.If hypoxemia or respiratory failure occurs, appropriate therapeutic measures should be given promptly, including oxygen therapy or mechanical ventilation. 2.When combined with shock, appropriate anti-shock treatment should be given. 3.When other organ function damage occurs, appropriate supportive treatment should be given. When combined with bacterial and/or fungal infections, appropriate antibacterial and/or antifungal drugs should be given. 5, For severe and critical cases, treatment with recovery plasma from recently recovered influenza A (H1N1) patients or immunized plasma from vaccinated patients may also be considered. For severe and critical cases within 1 week of the onset of the disease, it is advisable to use it at an early stage under the premise of ensuring medical safety. Recommended Use: Generally 100-200 ml for adults and 50 ml for children (or adjust the dosage according to the plasma-specific antibody titer), and enter intravenously. Repeated use can be made if necessary. In the process of use, pay attention to allergic reactions. (D) Traditional Chinese medicine identification and treatment. Treatment plan for identification of mild symptoms 1. Wind-heat offending the guard Main symptoms: at the early stage of the disease, fever or no fever, red and uncomfortable throat, mild cough with little sputum, no sweating. Tongue and pulse: red tongue, thin or greasy moss, floating pulse. Treatment: clearing away wind and heat. Basic formula: Yinhua 15g, forsythia 15g, mulberry leaf 10g, Hangzhou chrysanthemum 10g, platycodon 10g, burdock 15g, bamboo leaf 6g, rutabaga 30g, peppermint (later) 3g, raw licorice 3g, decoction: 400 ml in water, 200 ml orally each time, 2 times a day; 2 doses a day, 200 ml orally each time every 6 hours, if necessary. Add and subtract: add patchouli and pelargonium for thick and greasy moss; add almonds and loquat leaves for cough; add Chuanhuanglian and Guangmuxiang for diarrhea; add Jinlangdang for sore throat. Commonly used proprietary Chinese medicines: wind-dispersing and heat-clearing proprietary Chinese medicines, such as wind-dispersing and detoxifying capsules, Xiangju capsules, Yinqiao detoxification, Sangju colds and flu, Shuanghuanglian oral preparations; Huo Xiang Zhengqi, Puerariae baicalensis type of preparations, and so on. 2.Heat poison attacking the lungs Symptoms: high fever, cough, phlegm sticky sputum, thirst and drink, sore throat, red eyes. Tongue and pulse: red tongue, yellow or greasy moss, slippery pulse. Treatment: clearing the lungs and detoxifying the toxins. Basic formula: 3g of sizzling ephedra, 10g of almonds, 10g of raw licorice, 30g of gypsum, 10g of Zhi Mu, 10g of Zhe Bei Mu, 10g of Platycodon grandiflorus, 15g of Scutellaria baicalensis, 15g of Radix Bupleurum Chinense, 15g of Decoction: Decoction with water, 400 ml per decoction, 200 ml per oral intake, 2 times a day; 2 daily intakes if necessary, 200 ml per oral intake, 1 time every 6 hours. Add and subtract: add raw rhubarb for constipation; add Artemisia annua and Dampi for persistent high fever. Commonly used proprietary Chinese medicines: Qing lung detoxification class of proprietary Chinese medicines, such as Lianhua Qingdian capsule, Yinhuang class of preparations, Lotus clear heat class of preparations. Treatment plan for severe and critical illnesses 1. Heat and toxin congestion of the lungs Symptoms: high fever, coughing and sputum, yellow sputum, shortness of breath; or palpitation, agitation and restlessness, purplish lips. Tongue and pulse: red tongue, yellow or grayish moss, slippery pulse. Treatment: clearing away heat and diarrhea of the lungs, detoxification and dissipation of blood stasis. Basic formula: sizzling ephedra 5g, raw gypsum (first decoction) 30g, almonds 10g, motherwort 10g, fritillaria 15g, Draba hebecarpa 10g, buckwheat 10g, scutellaria baicalensis 10g, zhebeimo 10g, raw rhubarb 10g, dandelion skin 10g, Artemisia annua 15g, Decoction: water decoction, each dose of 400 ml, each time orally, 200 ml, 2 times a day; if necessary, can be taken 2 times a day, once orally every 6 hours. If necessary, two doses can be taken daily, one oral dose every 6 hours, 200 ml each time. Add and subtract: persistent high fever, delirium plus Angong Niuhuang Pill; convulsions plus antelope horn, stiletto, GuangDiLong, etc.; abdominal distension and constipation plus Citrus aurantium, YuanMing powder. Commonly used proprietary Chinese medicines: Xiyanping, phlegm-heat clearing, Qingkailing injection. 2, qi Ying two burnt Symptoms: high fever, thirst, irritability, or even delirium, cough or hemoptysis, chest tightness and shortness of breath. Tongue and pulse: red tongue, yellow moss, fine pulse. Treatment: clearing Qi and cooling the camp. Basic formula: buffalo horn 30g, Radix et Rhizoma 15g, Radix Paeoniae Alba 10g, Folium 15g, Salviae Miltiorrhizae 12g, Forsythiae 15g, Ophiopogonis Macrocephala 10g, Bamboo Leaves 6g, Piper betel 30g, Gypsum 30g, Gardeniae jasminoides 12g, Decoction: 400 ml in water, 200 ml orally every time, 2 times a day, 2 times a day, or 200 ml orally every 6 hours, if necessary. If necessary, it can be taken twice a day, every 6 hours by mouth, 200 ml each time. Add and subtract: add raw rhubarb for constipation; add antelope horn powder for high fever and limb convulsions. Commonly used proprietary Chinese medicines: Angong Niuhuang Pill, Haibi Jing, Wake up the brain Jing injection. Note: the above drugs should be used under the guidance of a physician; the dose is for reference, and the dose for children should be reduced; patients with complications and history of chronic underlying diseases should be treated according to the evidence. If shock, multiple organ dysfunction syndrome or other serious diseases are combined, the patients should be treated according to the actual situation while applying western medical treatment. IX. Discharge Criteria 1. The patient can be discharged if his/her body temperature is normal for 3 days, other influenza-like symptoms have basically disappeared, and his/her clinical condition is stable. 2.Influenza A (H1N1) cases that need to be hospitalized for a longer period of time due to more serious underlying diseases or comorbidities may be transferred from the isolation ward to the corresponding ward for further treatment after the nucleic acid test of influenza A (H1N1) virus in the pharyngeal swab has turned negative.