The pet’s immune system protects from diseases. The immune system is a very complicated system divided into two parts, cell mediated and humoral (blood) mediated. Each of these parts has many components working to protect our pets from getting diseases. There are parts of the immune system that react indiscriminately to a threat. Look at any abscess, the pus cells (white blood cells) are fighting the infection no matter what the bacteria causing it. And there are segments that are very specific to the threat. Vaccinate a pet against distemper and that segment of the immune system is primed for distemper only.
The pathogen (bacteria, parasite, or virus) can be fought at the exposure site, in the blood, and/or in a lymph node. Basically, the pathogen enters the host, certain cells release chemicals as a call to arms. The pathogen is tagged by either another cell and/or chemical (antibody) and presented for destruction or neutralization by another cell. Then certain times another cell is encoded with memory of this pathogen. Most memory is finite and some is lifetime.
A vaccine is an altered disease pathogen. A vaccine should not produce the illness if the pathogen has been altered correctly. So we get the benefit of protection without having to go through the disease.
Out of all this complicated immune system and all the cells interacting with each other, the only thing that can be measured are the antibodies in the blood. That measurement is called titer. A titer is a measurement for a specific antibody and specific disease. There is no other test that can measure all the cellular activity or the chemicals released to communicate between the cells, just the antibodies in the blood. There even is no test for antibodies that line mucous membranes like the nose, mouth, or gut. Therefore, most of the immune system that protects us is “invisible” to testing.
So what does titer testing tell us? That there are antibodies produced from some sort of exposure (natural or vaccine). As many immunologist and internist say “the numbers are meaningless.” There are no standards for what is protective and what is not. Vaccine companies do not use titers for testing their product, they use exposures. The vaccinated animal is exposed to the disease. Results are a simple “ got sick” or “did not get sick.”
So now what do we do?
1. Testing for several diseases in more costly than vaccinations.
2. As of right now, testing takes several days for the results.
3. No standard for interpretation of the titers.
4. Some diseases, the protection is local antibodies (IgA) which can’t be tested. Any intranasal vaccine stimulates the local immunity.
Pet owners want titers instead of vaccines. What is the best thing for the pet?
1. A lot depends on the pet’s family medical history. Or, breed predilections if the family medical history is unknown.
2. Risk assessment and environment is important to consider.
3. Three year vaccines are safer.
4. I have witnessed overdue pets getting sick.
5. Puppies and kittens need a series of vaccinations (see Part Three).
6. If pet owners want titers, then they are falsely assuming their pet will be protected based solely on titers.