It was lukewarm in previous years, but this year it’s so hard to get a shot?

As the weather turns cooler, the peak season for influenza has arrived. Vaccination is the most effective way to deal with influenza, which can significantly reduce the risk of influenza and serious complications. However, the influenza vaccine, which was not very popular in previous years, has become a rarity this year, and it is difficult to get a shot in many places across the country. What kind of disease is influenza? How to get the influenza vaccine? Why is there a shortage of influenza vaccines this year? What should we do if we cannot get the vaccine temporarily? Let's find out.

1. What is influenza and how is it different from the common cold?

The full name of influenza is influenza. Although it also has the word "cold", it is different from the common cold. Influenza is caused by influenza virus and is an acute respiratory infectious disease that poses a serious threat to human health. The clinical features are rapid onset of high fever, fatigue, muscle aches, and mild respiratory catarrhal symptoms; the common cold is commonly known as "cold". Most adults are caused by rhinovirus, but there are also other viruses. Generally, there is no fever and systemic symptoms, or only low fever, general discomfort, mild chills and headaches. The onset of influenza is seasonal and may cause an outbreak or pandemic; the common cold can occur in all seasons, mainly sporadic, with a higher incidence in cold seasons, and will not cause a pandemic. The common cold can also cause some serious chronic complications, such as myocarditis and chronic nephritis, but they are relatively rare, and influenza patients may suffer from bronchitis and pneumonia, which may even threaten the patient's life in severe cases.

The "culprit" of influenza - influenza virus belongs to the Orthomyxoviridae family. It is a single-stranded, negative-stranded, segmented RNA virus, which can be divided into types A, B, C, and D (or A, B, C, and D). Influenza A virus can be divided into multiple subtypes. Not all influenza viruses will spread among humans. Currently, the viruses that cause seasonal influenza epidemics are the H1N1 and H3N2 subtypes of influenza A and the Victoria and Yamagata strains of influenza B virus.

1. Vaccine is the most important way to prevent influenza

Vaccines are any preparations that are intended to stimulate the production of antibodies to form immunity to a disease. In vaccine production, pathogenic microorganisms are removed from the substances that can cause disease, while retaining the properties that can stimulate the human body to produce an immune response. When the body is vaccinated, the antigen molecules in the vaccine will stimulate the body's immune system to produce immune protective substances. When the body is exposed to the same antigen again, the immune system will quickly produce more protective substances based on immune memory, allowing the body to gain specific immunity against pathogens.

The trivalent inactivated influenza vaccine (IIV3), quadrivalent inactivated influenza vaccine (IIV4) and trivalent live attenuated vaccine (LAIV3) are currently approved for marketing in my country. IIV3 includes split vaccine and subunit vaccine, IIV4 is a split vaccine, and LAIV3 is an attenuated vaccine. Although vaccines are currently the most effective means of preventing influenza, people who have been vaccinated should also be wary of the risk of contracting influenza. Immunity acquired after a person is infected with influenza virus or vaccinated with influenza vaccine will decay over time. Regardless of whether or not a flu vaccine was administered in the previous season, it is still recommended to be vaccinated again before the flu season of the current year. In addition, it should be noted that drug prevention cannot replace vaccination and can only be used as one of the emergency temporary preventive measures.

1. Why is influenza vaccine in short supply? What should we do if it is difficult to get a shot?

The demand for influenza vaccines has surged this year, mainly due to the COVID-19 pandemic. In August, WHO officials publicly stated that because the symptoms of COVID-19 and influenza are difficult to distinguish, and medical resources are limited, countries should increase the influenza vaccination rate to resist influenza and focus on fighting the epidemic. In fact, the market supply of influenza vaccines in my country this year has increased significantly compared with previous years, but the demand for influenza vaccines has surged in the short term, and its production cycle is long, and it is restricted by national vaccine approval and production mechanisms, resulting in a temporary imbalance between supply and demand.

In fact, it is not necessarily a bad thing that the flu vaccine is hard to get. The public's active vaccination is not only conducive to avoiding the superposition of influenza and COVID-19, but also can greatly improve the health literacy of the whole people and enhance the overall ability of society to prevent influenza and COVID-19. People who have not been able to get the flu vaccine do not need to panic: in daily life and work, do a good job of hand hygiene and isolate the source of infection, try to avoid crowded and enclosed places, wear a mask when going out, take good protection, and wash hands frequently; if you have upper respiratory tract symptoms such as fever and cough, you should seek medical treatment in time, and it is best not to work or study while sick; people at high risk of severe influenza with a clear history of exposure can use neuraminidase inhibitors to prevent influenza under the guidance of a doctor. You should know that maintaining good personal hygiene habits is also the most powerful weapon for everyone to fight against influenza, and it is the best "social vaccine".

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