What are the symptoms of chicken getting bird flu?

Introduction of avian influenza virus Avian influenza is the abbreviation of avian influenza, which is an infectious disease syndrome caused by a subtype of influenza A virus. It is classified as a class A infectious disease by OIE International Bureau, also known as true chicken plague or European chicken plague. Not only chickens, but also some other poultry and wild birds may be infected with bird flu. According to the types of pathogens, avian influenza can be divided into three categories: high pathogenicity, low pathogenicity and no pathogenicity. Non-pathogenic avian influenza does not cause obvious symptoms, but only produces virus antibodies in infected birds. Low pathogenic avian influenza can lead to mild respiratory symptoms, decreased food intake, decreased egg production and sporadic deaths in poultry. Highly pathogenic avian influenza is the most serious, with high morbidity and mortality, and infected chickens are often "completely annihilated". The earliest bird flu was recorded in 1878, and a large number of chickens died in Italy, which was called chicken plague at that time. By 1955, scientists confirmed that its pathogenic virus was influenza A virus. Since then, the disease has been renamed avian influenza. Since the discovery of avian influenza 100 years ago, human beings have not mastered effective prevention and control methods, and can only prevent its spread by disinfection, isolation and mass slaughter of livestock and poultry. Areas where highly pathogenic avian influenza breaks out often suffer huge economic losses. Under normal circumstances, avian influenza virus is not easy to cause human illness. Avian influenza virus belongs to influenza A virus, and influenza A virus is divided into 15 subtypes according to its surface protein, such as H 1 to H 15. Avian influenza worldwide is mainly caused by highly pathogenic H5 and H7 subtypes, and people are susceptible to H 1 and H3 subtypes. At present, the avian influenza virus prevalent in Korea and Japan belongs to H5N 1 type, which usually only spreads among birds and rarely infects humans. Although there have been cases of human infection with avian influenza virus, such as 1997 avian influenza in Hong Kong, which made 12 people sick and six of them died, this situation is really rare. In addition, the main route of human infection with avian influenza virus is contact infection, and no cases of infection due to eating chicken and eggs have been found yet. From the microbiological point of view, there are three reasons to prevent the invasion of avian influenza virus to human beings. First of all, human respiratory epithelial cells do not contain the specific receptor of avian influenza virus, that is, avian influenza virus is not easily recognized and combined by human cells; Second, the genomes of all influenza viruses that can spread from person to person must contain several gene fragments of human influenza virus; Thirdly, highly pathogenic avian influenza virus contains a lot of basic amino acids, which is difficult to replicate in human body. However, although there is no evidence that avian influenza virus will directly cause human influenza outbreaks, from the evolutionary point of view, human influenza is related to the influenza virus that first spread in animals. It is likely that in the process of human domestication of pigs, chickens and other animals in history, due to frequent contact between humans and animals, some strains of swine flu and avian influenza virus have mutated, acquired the pathogenicity to humans and the ability to spread among people, and became human influenza viruses. This kind of incident may happen again, so medical research and monitoring departments are still alert to the possibility of bird flu attacking human beings. For individuals, we should pay attention to good health and maintain good immunity; Before eating poultry products, cook them at high temperature to kill the virus. So far, there has never been a case of human infection with highly pathogenic H5N 1 avian influenza virus in Chinese mainland. China has established technical means for rapid detection of avian influenza. A few years ago, the Ministry of Health strengthened the monitoring of influenza epidemic, including avian influenza, and the trends of various influenza viruses were being monitored.