May 16th, 2007

Leptospirosis vaccine updated!

Noah's 24-Hour Animal Medical Center is pleased to announce that effective May 16th, 2007, we will be including the NEW Leptospirosis vaccine in our vaccine packages. Leptospirosis is a zoonotic disease (diseases caused by infectious agents that can be transmitted between (or are shared by) animals and humans). Please read the following important information regarding the improvements that were made to the vaccine.

Annual Revaccination and Leptospirosis

Current concerns in canine immunology have addressed issues related to overuse of vaccines in dogs and cats. General consensus among specialists in the field is that yearly vaccination against viral infections associated with canine distemper virus, canine parvovirus and canine adenovirus are generally unnecessary since active immunity induced by these vaccines provide at least several years of protection. This consensus, however, does not apply and should not be generalized to bacterin vaccines, which immunize against diseases associated with bacterial organisms. In fact, clinical evidence suggests that bacterin-derived vaccines including those which protect against Bordetella bronchiseptica (kennel cough), Leptospira (Leptospirosis), and Borrelia burgdoferi (Lyme disease) probably don't even provide protective immunity for 12 months suggesting that more frequent vaccination for these diseases are required. It is perhaps the common use of combination (all-in-one) vaccines containing bacterins, which immunize against bacterial infections such as Leptospirosis and/or kennel cough in addition to common viral infections, that gave rise to the practice of frequent vaccine administration. Indeed the incorrect generalization of long-term immunity, associated with vaccination against viral immunogens, to bacterin-based vaccines may lead to a decrease in annual vaccination for bacterial-based diseases and subsequently give rise to a resurgence of outbreaks of bacterial disease in the coming years. In light of this, annual re-boostering against bacterial diseases should continue despite discontinuation of yearly vaccination against viral diseases.

The Current Leptospirosis Vaccine

Recent serological studies on wildlife and domestic dogs suggests that L. grippotyphosa and L. pomona have replaced L. icterohaemorrhagiae and L. canicola as the prevalent serovars responsible for Leptospirosis in the United States today. As such, current commercial vaccines, which protect against the formerly prevalent serovars, would not be effective at providing immunity against Leptospirosis caused by L. grippotyphosa and L. pomona. For this reason, there has been some conjecture that current commercial vaccines should be considered obsolete for protecting against Leptospirosis. There are several factors that should be considered prior to drawing this conclusion. First, Leptospirosis vaccines, as mentioned above, protect against clinical disease but do not prevent subclinical infection to a "carrier" state. That is, a dog that is annually vaccinated may harbor infectious organisms of L. icterohaemorrhagiae or L. canicola which will pose a risk of contagion to dogs that are not vaccinated or in which vaccination for these serovars has been discontinued. Without serological testing, low clinical incidence of these formerly prevalent serovars may be a result of the currently large population of vaccinated dogs. If this is the case, discontinuing administration of the current Leptospirosis vaccine may result in a resurgence of clinical disease. Furthermore, it is important to note that samples from these studies are not necessarily representative of all regions of the US.

When all the facts are considered, these findings do not necessarily suggest that L. icterohaemorrhagiae and L. canicola no longer pose a threat to dogs. Rather, this information should be taken into consideration when determining potential risk of infection in dogs that may be candidates for side effects associated with vaccine-reaction. Leptospirosis-containing vaccines are associated with a higher risk for side effects, particularly, anaphylactic reactions (see Canine Anaphylaxis). Taken together, benefits of vaccinating dogs, who live in areas where icterohaemorrhagiae and canicola incidence is low and who may have a higher predisposition for vaccine side effects with current Leptospirosis inoculants (see Vaccines, Infectious Diseases and the Canine Immune System), may not outweigh risks of vaccine reaction.

New Leptospirosis Vaccine Immunizes Against L. grippotyphosa and L. pomona

Noah's 24-Hour Animal Medical Center now offers the Duramune Leptospirosis vaccine that immunizes against L. grippotyphosa and L. pomona serovars as well as L. icterohaemorrhagiae and L. canicola . This vaccine has been formulated through the new subunit technology that uses only the antigen component of the organism (that will produce an immune response) instead of the entire organism. As such, subunit vaccines greatly reduce vaccine side-effects that occur with higher incidence with bacterin-based vaccines while providing durable protection from the disease.

For even more information regarding the NEW Leptospirosis vaccine, click here....