November 1st every year is World Influenza Day. In autumn and winter, the temperature changes significantly, and it is also a high-risk period for various respiratory diseases such as influenza. What is the difference between flu and common cold? How to prevent influenza most effectively? Recently, our reporter interviewed Wang Yimin, the deputy chief physician of the Department of Respiratory and Critical Care Medicine of China-Japan Friendship Hospital. Influenza ≠ Common Cold: High risk individuals should be cautious. Reporter: Are influenza and common cold the same thing? What is the difference between the two? Wang Yimin: Influenza is different from the common cold. The full name of influenza is influenza, which is an acute respiratory infectious disease caused by influenza virus. Influenza viruses are divided into four types: type A, type B, type C, and type D. However, type A and type B are mainly prevalent in humans, with type A influenza being more common. At present, the main types of human infections are H1N1 and H3N2 subtypes of influenza A virus and Victoria and Yamagata strains of influenza B virus. The common cold is usually caused by viral infections, including rhinovirus, adenovirus, respiratory syncytial virus, and a small number of bacterial infections. The clinical symptoms of the common cold are usually mild, mainly manifested as runny nose, cough, nasal congestion, sore throat, fever, etc. (usually manifested as low-grade fever), which usually self heal within one week and rarely affect normal work and study. Compared to the common cold, influenza is highly contagious, has a rapid onset, more severe symptoms, and greater potential harm - it not only affects the respiratory tract, but also causes systemic symptoms such as high fever (usually exceeding 38.5 degrees Celsius), headache, joint pain, muscle soreness, fatigue, and decreased appetite. It may also cause complications such as pneumonia, myocarditis, hepatitis, encephalopathy, septic shock, etc. Among them, pneumonia is the most common complication, and in a few severe cases, the condition progresses rapidly and can lead to death due to acute respiratory distress syndrome or multiple organ failure. Some people are at higher risk of developing serious complications after being infected with influenza virus, including elderly people aged 60 and above, children under 5 years old, pregnant women, and patients with underlying diseases. Reporter: According to your observation, has there been any change in the number of flu patients who have come to the hospital for treatment recently? Has the seasonal peak of popularity arrived? Wang Yimin: Recently, there has been little difference in the number of influenza patients in the fever clinic, emergency department, respiratory department, and pediatric clinic of the hospital compared to the previous period, and there has not been a significant seasonal epidemic peak. However, this does not mean that we can take it lightly. Past experience has shown that the peak period of influenza is usually concentrated from late November to March of the following year. We still need to take precautions and remain vigilant. Reporter: What are the main ways of transmission of influenza? Wang Yimin: Influenza virus is mainly transmitted through respiratory droplets produced by infected individuals sneezing and coughing, and can also be directly or indirectly transmitted through mucous membranes such as the mouth, nose, and eyes. In specific places, such as densely populated and enclosed or poorly ventilated rooms, aerosol transmission may also occur. The general population is susceptible to influenza virus, and influenza patients and asymptomatic carriers are the main sources of influenza transmission. Therefore, in daily life, we should take protective measures such as wearing masks, washing hands frequently, and maintaining social distance to reduce the chances of virus transmission. Getting vaccinated against influenza is the most direct and effective way to prevent it. Reporter: How to prevent influenza most effectively? What measures can the public take? Wang Yimin: Getting vaccinated against the flu is the most direct and effective way to prevent the flu. It is generally recommended to get vaccinated before the flu season begins, such as now. According to the types of viruses covered by vaccines, influenza vaccines include 3-valent and 4-valent influenza vaccines, where "valent" refers to the number of virus types and subtypes covered by the vaccine. The trivalent influenza vaccine can prevent infection with three subtypes of influenza viruses, including H1N1, H3N2, and Victoria virus; The 4-valent influenza vaccine can prevent infection with four subtypes of influenza viruses, including H1N1, H3N2, Victoria and Yamagata influenza viruses. All individuals aged ≥ 6 months and without contraindications for vaccination should receive the influenza vaccine, especially high-risk groups such as the elderly, weak, pregnant, and young, including those over 60 years old, those with chronic underlying diseases, pregnant women, and children under 5 years old. In addition, some specific occupational groups, such as healthcare workers, vulnerable populations and employees in gathering places such as nursing homes, kindergartens, welfare institutions, primary and secondary school teachers, caregivers or family members who take care of infants and the elderly, are recommended to receive influenza vaccines as long as there are no contraindications. Reporter: Why is the flu vaccine administered annually? Wang Yimin: Influenza viruses are prone to mutation, and the influenza virus strains targeted by influenza vaccines in different years may vary. Therefore, we prepare new influenza virus vaccines every year based on the mutation situation of the virus prevalent in the previous year; Meanwhile, the immunity obtained after vaccination will weaken over time. To provide more effective protection, it is recommended to receive the flu vaccine annually. The current influenza vaccine has been developed and improved for many years, and its effectiveness and safety are guaranteed. Although there may be slight discomfort reactions after vaccination, these reactions are controllable and seem insignificant compared to the protective effect brought by the vaccine. Reporter: Some people have reported that after receiving the flu vaccine, why did they still get hit? Wang Yimin: It is indeed possible that this situation exists, and the main reasons may be as follows: no vaccine administered to the human body can achieve 100% prevention, and influenza vaccine is no exception; Although influenza vaccines may not completely prevent the occurrence of influenza, they can effectively prevent severe illness caused by influenza and reduce the impact of danger and severity; The protective effect of influenza vaccine is achieved by producing protective antibodies, which take time to develop, usually within 2 to 4 weeks after vaccination. For populations with lower immunity, antibody production may be slower and take longer. During the time window before antibody production, if exposed to influenza virus and infected, the vaccine may not provide protection and there is a possibility of missing the protection time window. In recent decades, research and practice have proven that receiving influenza vaccines is an effective means of preventing influenza and reducing influenza related severe illness and death. In addition to getting vaccinated against influenza, we should also pay attention to personal hygiene, clean and disinfect our hands; Pay attention to indoor ventilation and keep the air fresh; Avoid crowded and poorly ventilated public places, and wear masks if necessary; Ensure sufficient sleep, balanced diet, and strengthen physical exercise. Do not self medicate with antibiotics. Take antiviral drugs as soon as possible after diagnosis. Reporter: If you experience flu symptoms, should you go to the hospital for examination? Can I wait for self recovery or take medication at home? Wang Yimin: It depends on the situation. Influenza is mostly self limiting, which means it can relieve on its own. It usually takes 3-5 days for the fever to subside, and symptoms such as coughing and fatigue gradually improve. For example, young people who have no underlying diseases and have the flu can observe and rest first. If the symptoms are mild, they can alleviate them by resting, drinking more water, and receiving targeted treatment; If there is persistent high fever, suffocation, wheezing, shortness of breath, or blood in sputum, decreased blood oxygen saturation, etc., it indicates that the condition has worsened and immediate medical attention should be sought. For high-risk individuals and flu patients with severe symptoms, especially elderly people with underlying diseases, it is recommended to seek medical attention promptly when experiencing symptoms such as fever, cough, headache, and fatigue. If diagnosed with flu, appropriate antiviral drugs should be used early to reduce the risk of worsening of the condition. If patients experience other complications or worsening underlying diseases during the flu period, they should also seek medical attention promptly. There are also some precautions for taking targeted medication at home. The first thing to note is not to abuse antibiotics on your own. Antibiotics are ineffective in treating influenza because antibiotics mainly target bacterial infections, while influenza is caused by viruses. If there is a mixed infection, medication should be taken under the guidance of a doctor. Before taking antiviral drugs, it is important to check their interactions with existing medications such as antihypertensive and hypoglycemic drugs. When taking medication, factors such as weight, liver and kidney function should also be considered, and the dosage of medication should be adjusted according to liver and kidney function. Reporter: If someone around me has the flu, is it necessary for others to take medication in advance to prevent it? Wang Yimin: It is not recommended to take medication to prevent influenza before coming into contact with a flu patient, as it is unnecessary. If you have had close contact with a flu patient and are very concerned about being infected, you can take oral antiviral drugs for prevention, which is called "post exposure prophylaxis". For preventive measures before exposure, it is recommended to reduce the risk of infection by wearing masks and washing hands frequently before coming into contact with flu patients, without the need for medication. If a family member is infected with influenza, it is important to pay close attention to the infected person, encourage them to take antiviral medication as soon as possible, and reduce contact with other family members. Early treatment for infected individuals not only helps with their own recovery, but also reduces the risk of infection for family members, especially when there are high-risk groups such as elderly people, patients with underlying diseases, or children in the family. In this case, other family members do not need to take medication in advance to prevent it, but should allow the infected person to receive treatment as soon as possible to reduce the risk of virus transmission within the family. Reporter: If confirmed to have the flu, how should it be treated? Wang Yimin: Once diagnosed with influenza, antiviral medication can be taken as early as possible under the guidance of a doctor. 48 hours after onset is the golden period for influenza treatment, during which the virus replicates actively. Early medication can improve symptoms, shorten the course of the disease, and reduce the probability of severe illness. At the same time, targeted treatment is also needed, such as using antipyretics when high fever occurs and cough suppressants when severe coughing occurs. As we mentioned earlier, antibiotics only target bacterial infections and do not directly treat influenza, but severe influenza patients often have concurrent or secondary bacterial infections. The influenza virus invades the human airway epithelium like a raging fire, presenting a "burn like" appearance. Severe damage can easily attract other bacteria, such as bacteria and fungi, and antibiotics are needed to take effect. It needs to be clarified that this requires professional doctors to make a judgment. Reporter: If you get the flu, won't you get it again soon? Will a person be infected with different influenza viruses in the short term? Wang Yimin: If you get the flu once, you usually won't get it again in the short term. However, over time, such as every six months, antibody levels gradually decrease, and there is a possibility of reinfection. Can a person be infected by different influenza viruses? This is possible because there is no cross immune protection between different types of influenza viruses, but the probability is relatively low. The probability of simultaneous outbreaks of both H1N1 and H1N1 influenza in the same season is relatively low, and the probability of the same person being continuously infected by both types of viruses in a short period of time is also relatively low. It should be noted that after getting the flu, it is important to rest well and not to work immediately. It is also important to pay attention to changes in physical symptoms. If you experience symptoms such as coughing, coughing up pus, and phlegm, be careful if there is a secondary bacterial infection, as the airway mucosa is damaged after influenza and is easily invaded by other bacteria during the repair process. To protect oneself, it is recommended to continue wearing masks in public places. (New Society)