Pascual Hernandez
Pascual Hernandez

With all the recent livestock vaccinations against anthrax, it might be worthwhile to look into how immunity works. While it doesn’t offer perfect protection, vaccination is the most effective tool to prepare an animal’s immune system to disease challenges.

The first time an animal’s immune system is exposed to a pathogen, it usually can’t respond quickly enough to prevent disease. However, the immune system often succeeds in subduing the infection over time. After an animal recovers from an infection, memory cells produced by the immune system remain for months or years.

These memory cells recognize parts of a pathogen’s body called antigens (molecules unique to each pathogen). This recognition brings about a response before the pathogen can cause disease.

Vaccines work by exposing the immune system to antigens from a specific pathogen, tricking the body into thinking is has encountered the actual pathogen. Exposure to an antigen stimulates an immune response, which creates memory cells for that pathogen without causing the negative effects of an actual first infection.

Secondary exposure to a pathogen or its vaccine makes the immune system stronger and better prepared for future exposure. This is because some memory cells have a longer lifespan than others.

A booster (second vaccination) creates a stronger immune response of longer duration as the concentration of memory cells and their efficacy increase with repeated exposure to an antigen.

This explains why one vaccination may not provide sufficient protection. Many vaccines require a booster two to four weeks after the first vaccination and annually thereafter.

The goal is to stimulate the immune system by repeated exposure to an antigen so antibodies are present in the body at a level that is highly protective if exposure to the actual pathogen occurs. Even so, disease may still occur in cases where pathogen exposure exceeds the animal’s protective level for that disease.

To improve immune response, always follow label directions for timing, route of administration, and proper vaccine handling. Also keep in mind that exposure to heat, sunlight, or being mixed too long before use can reduce a vaccine’s effectiveness. And, it is important to understand that stress, vitamin and mineral balance, nutrition, and overall health of the animal can influence the immune response to vaccinations.

Involve your veterinarian- he or she can help you develop a sound vaccination program with proper timing and technique.