Construction of the first line of defense against avian influenza by mucosal immunization

Construction of the first line of defense against avian influenza by mucosal immunization

Influenza is a kind of conditional disease. According to the analysis of relevant data and clinical research results, avian influenza virus is widespread in poultry in recent years, and most of them are recessive infection, latent in the trachea mucosa or environment of poultry. Because avian influenza virus is sensitive to low temperature and cold wind, if domestic birds are stimulated by these stress factors, they are easy to get sick, and the onset of avian influenza is acute, spread quickly, and give rise to severe illness Poultry life is threatened.

So, how to prevent avian influenza in poultry scientifically and perfectly?

The causes of avian influenza

1. The avian influenza virus is cold resistant and heat-resistant and is conducive to horizontal transmission.

Especially in spring, the sun is relatively weak, and the killing effect of avian influenza virus is relatively poor, so the chances of virus survival in the environment increase. Because of the high wind saving in spring, the virus spread rapidly with the air and dust.

2. Improper feeding management and poor air quality of chicken house.

For example, the concentration of harmful gases such as NH3 and H2S increases, which seriously damages or stimulates local mucosa tissues, such as nasal cavity, trachea, conjunctiva, etc., which causes the damage of lymphoimmune tissue in submucosa, and damage or loss of local mucosal barrier, which causes influenza virus invasion into the blood system of the body, leading to infection and morbidity.

3. Avian influenza virus strains and vaccines are not of the right type.

Because of the large number of serum types of avian influenza, there are often variations, and there will be different strains of influenza in different places, which often leads to the ineffective vaccination.

4. High antibody replication and detoxification.

That is, high antibody titer can not inhibit the replication and transmission of the virus, especially mild avian influenza virus. The simple humoral immunity can not effectively prevent and control the avian influenza virus.

5. At present, the inactivated vaccine is generally used for the prevention and control of avian influenza.

However, inactivated vaccine can only produce humoral immunity and the immune blank period is long, and it can not produce effective mucosal immunity. Influenza virus is very easy to enter the body from respiratory mucosa, leading to the disease of poultry.

6. Mycotoxin, parasite, immunosuppressive diseases and so on lead to low immunity of poultry, which is also an important inducement.

Prevention and control strategy of Early Spring Avian Influenza

1. Biosafety is the theme of eternity and is fundamental.

Usually pay attention to disinfection, do well in heat preservation and ventilation work, to avoid cold air attack poultry.

2. The scientific integrated immunization program needs to be further completed.

From the current influenza prevention and control, the phenomenon of high antibody detoxification is worth paying attention to! It is difficult to control the transmission of virus by inactivated vaccine. Because the antibodies in blood have little effect on the influenza virus on the mucosa, more than 95% of influenza viruses enter the body from the mucosa. Therefore, in poultry immunity, only mucosal immunity and humoral immunity are established to protect poultry efficiently and reduce the occurrence of influenza diseases. But humoral immunity is the most common vaccine injection. With the development of science and technology and the deepening of research, mucosal immunity has become a hot research topic in recent years, which provides technical support for comprehensive prevention and control of influenza.

3. Pay attention to the effect of mucosal immunity on avian influenza

On March 14, the Global Forum on mucosal immunity will be launched ceremoniously, and many experts are calling for the importance of mucosal immunity. Because most infectious diseases are transmitted through respiratory tract, digestive tract and urogenital tract, we should pay attention to the immune work of invasion portal, respiratory mucosa, digestive tract mucosa and reproductive tract mucosa in the prevention and control of diseases.