Injection time is incorrect

Puppies mainly rely on maternal antibodies obtained in breast milk to resist the invasion of the virus. Dogs with early breast milk may have been infected with the virus before their first immunization. If the maternal antibody level is too high, it will neutralize the vaccine effect, resulting in the inability to succeed in immunization. Therefore, the time for the first immunization is very important.

The antibodies are less than  

Immunization is to allow the body to produce antibodies to resist the invasion of the virus. Infectious diseases can only be prevented when the serum antibody titer is greater than 10 international units per milliliter. Therefore, before completing all injections, if the antibody is not produced or the titer is relatively low, there is still a possibility of infection.

Virus or bacterial strain mutates

If the virus or bacterial strain mutates, the immunity will also fail. For example, the gene drifts of canine parvovirus has occurred several times, and vaccines made from the original strain will not play a protective role.

Vaccine quality issues

Currently, the virus vaccines commonly used in China are mainly divided into two categories: attenuated vaccines and inactivated vaccines. If the attenuated vaccine is successfully vaccinated, it can produce a strong and lasting immune effect, but due to problems such as impurity of the strain, stability problems are likely to occur; inactivated vaccines are relatively safe, but their effects are weak, and multiple injections may require sufficient antibodies.

Vaccine transport and storage issues

Vaccine cannot guarantee low temperature during transportation and storage; after the vaccine is removed, it is directly exposed to sunlight before vaccination or taken out for too long, resulting in a decrease in the activity of the vaccine, and various problems can cause immunity failure.

Improper use of the vaccine

The vaccine is not released with a special diluent according to the instructions for use, or is not used up within the specified time after dilution, resulting in a greatly reduced stability of the vaccine;

During the process of dilution or vaccination of vaccines, excessive disinfectant drugs remain on the syringe, or the disinfectant comes into contact with the vaccine directly, causing the vaccine to fail or de-effect;

The vaccine injectors have not received professional training, are not proficient in injection operations, missed injections, and inaccurate immunization doses, and are not vaccinated according to the prescribed methods of the vaccine, etc., which can all cause vaccination failure.

The poor condition of immunized objects

Young pets experience transportation, bathing, environmental changes, etc., causing stress, resulting in decreased immunity, malnutrition, not undergoing internal and external deworming procedures, being infected with the virus or incubating the latent period, being subject to unscrupulous merchants to inject serum in advance, etc., can all cause immunity failure.