Vaccines are a hot topic in human health care and animal health care. There has been a lot of talk over the past 10 years on whether vaccines do more harm than good and this article will try to go back to the basics and discuss how vaccines work, why we use them and why they are still an important part of preventive health care.
The main function of vaccines is to stimulate the body to produce antibodies. These antibodies are small bits of protein that travel in the blood stream. When an invading virus enters the body (by the nose, the mouth, by an insect bite) these antibodies attach to the virus and signal white blood cells to come and kill the virus. By doing this, antibodies either prevent disease completely or make the illness the patient suffers from much less severe.
As mentioned above, antibodies are small bits of protein circulating in the blood stream. Antibodies are produced either by infection with a particular disease (virus / bacteria) or in response to a vaccination. With either of these forms, the disease/vaccine is taken up by specific white blood cells and these white blood cells find their way to a lymph nodes where the “antibody factories” are found. In the lymph nodes, antibodies are produced to attack and deactivate more of the invading pathogens.When animals are first exposed to a disease it takes the antibody ‘factories’ in the lymph nodes between 7-20 days to “gear up” to produce adequate numbers of antibodies. The second, third and any other time the animals are exposed to the same disease these “antibody factories” are built and just need to be turned on. This process is much faster taking only 1-2 days to turn on the “antibody factories”.
This is the whole premise behind using vaccinations. Exposing the pet to a form of the virus that does not cause illness but does build the “antibody factories” allows the pet the ability to quickly turn on antibody production when exposed to a real infection. Vaccination does not prevent infection but it does allow the body to get rid of the infection before the animal gets sick.
With naturally occurring infections, “antibody factories” are made in the same way as with vaccines. The problem when a pet is first exposed to the disease is, just like with vaccines, the first exposure stimulates the building of “antibody factories” and it takes from 7-20 days before they can churn out enough antibody to fight the infection. With diseases like Canine Parvovirus, Feline rhinotracheitis and rabies, this allows the disease to become active and possibly even fatal before a protective level of antibodies can be made and circulated in the blood stream. Once the infection is in the cells of the body, it is hard if not impossible for the antibodies to get to them. When animals are vaccinated appropriately the antibodies are available to fight invasion by disease and prevent illness.
The first vaccine was developed in 1796 by Edward Jenner against Smallpox in people. This was a crude vaccination where the pus of an infected scab was placed on a cut on another person’s arm. The disease causing virus was allowed into the body this way and a mild form of the disease was experienced by the person being inoculated. By doing this, the person ‘vaccinated’ was allowed to develop antibodies to the invading virus before getting sick. The “antibody factories” were built and ready to churn out protective antibodies. Now days, the process of developing vaccinations is much more complex and vaccines currently used have either killed or modified virus in them. These newer vaccines allow antibodies to be created often without the animal getting ill at all and if they do fall ill from the vaccine, the illness is short.
Vaccinations are a very important part of preventive health. They prevent sickness and in many cases prevent death. These days it is possible to help sick patients recover from some of the viral diseases but this always entails a long stay in the hospital and costs a great deal. Vaccines are far cheaper and most of the time any pain and suffering associated with the illness.
If you have any questions about vaccinations please contact North Hill Animal Hospital at your earliest convenience to request further information!