Breeds that are predisposed genetically to yeast infections :Cocker spaniel, Dachshund, Basset hound, Poodle, Lhasa Apso etc.

Malassezia dermatitis is usually associated with bacteria and most common are :-

Skin : Staphylococcus intermedius

Ears : Staphylococcus intermedius, Pseudomonas aeroginos.

Where would a dog get a yeast infection?

Yeast is normal inhabitant of skin, ears and anol glands. To get a yeast infection, conditions on the skin surface have to change to favour the proliferation of the yeasts. The yeasts in small normal numbers are harmless but when the yeasts are present in large numbers, disease results.

What are the conditions that lead to yeast proliferation?

An increase in skin oils (which often occurs in an skin allergy) would be the most common situation. Sometimes there is a immune deficiency, which allows the yeast proliferation. Some animals are battling seborrhea (excessive oil production of the skin) and thus are naturally predisposed to the yeast proliferation. Some animals are actually allergic to the yeasts themselves. The most important thing to realize is that yeast infections are not contagiuos but they tend to recur unless the underlying allergy, seborrhea or whatever problem is controlled.

HOW DO WE GET RID OF YEAST INFECTION?

Treatment can be topical / oral or both. Topical treatment alone is not usually adequate. Since oral medications are expensive, often topical management alone is attempted first, especially if the pet is small enough for convenient frequent bathing or if only a small body area is involved.

Topical therapy - Shampoos : While degreasing shampoos such as the Benzoyl Peroxide and sulfur/salicylate shampoos will help remove the skin oils feeding the yeast, there are shampoos that are specifically anti-yeast. The pet must be bathed twice a week to start and the shampoo requires a 15 minute contact time ( meaning do not rinse the lather for 15 minutes)

Oral therapy - Ketoconazole: Typically a several week treatment is needed and there are numerous protocols involving different dosing schedules. Higher doses tend to be needed if recurrence is a problem. The extreme itch usually resolves withing one week. This medication is expensive, especially in larger dogs, but often there is no way around its use.

Treatment of the underlying case : It is important to realise that yeast overgrowth occurs in response to a primary problem be it allergy, seborrhea or something else. If the underlying problem is no controlled, yeast dermatitis is likely to periodically recur.

ADMINISTRATION OF VACCINES

The simplest and the most common method is SC or IM injection. This approach is excellent for relatively small numbers of animals and for diseases in which systemic immunity is important.

MIXED VACCINES

Because of the complexity of many disease syndromes, it is common to use mixtures of organisms in single vaccines. Mixed vaccines are often used to protect animals against several different agents with economy of effort, but it may be wasteful to use vaccines against organisms that are not causing problems. In addition, when a mixture of different antigens is inoculated simultaneously, competition may occur between them. However, manufacturers have recognized this and modified vaccines accordingly. Vaccines should never be mixed indiscriminately because one component may dominate and interfere with response to the other components.

VACCINATION SCHEDULES

Although it is impossible to give exact schedules for each vaccine, certain principles are common to all methods of active immunization. New born animals may be passively protected by maternal antibodies. If stimulation of immunity is deemed necessary at this stage, the dam may be vaccinated during the later stages of pregnancy, timing the doses so that peak antibody levels are reached at the time of colostrums formation. Successful active vaccination was previously thought to be possible only after passive immunity has waned. Neonatal animals with certian levels of pathogen-specific, detectable antibodies were thought to be protected against disease caused by that pathogen. Recent studies in puppies born to bitches immunized against rabies during pregnancy have determined that passive antibody titers decrease significantly by 6 weeks of age. Puppies vaccinated at 7 and 11 week of agae with a recombinant vectored rabies virus were all solidly protected against rabies, even though many of them had high levels of maternal antibody is present. With the availability of these new recombinant vaccines, the age of and interval between vaccinations may have to be reconsidered. Because the exact time of loss of maternal immunity cannot be predicted, young animals are predicted, young animals are often vaccinated at least twice to ensure succesful immunization.

The interval between doses varies : some vaccines may require administration every 6 months. The interval between doses is also determined by the disease. Some diseases are seasonal, and vaccines may be given before expected disease outbreaks.

FAILURES OF VACCINATION

There are many reasons why vaccination may fail. In some cases, the vaccine may not be effective because it contains strains of organisms or antigens that are different from the disease-producing agent. It other cases, the method of manufacture may have destroyed the protective epitopes, or there may simply be insufficient antigen. Such problems are relatively uncommon and generally can be avoided by using vaccines from reputable manufacturers. An effective vaccine may fail due to unsatisfactory administration. For example, a live vaccine bacterial vaccine, chemical sterilization of syringes, or excessive use of alcohol on the skin. Administration by non conventional routes may also affect efficacy.

If an animal is incubating the disease before vaccination, the vaccine may not be protective; vaccination against an already contracted disease is usually impossible.

The immune response, being a biologic process, never confers absolute protection nor is equal in all individuals of a vaccinated population. Because the response is influenced by many factors the range in a random population tends to follw a normal distribution; the response will be "average" in most animals, excellent in a few, and poor in a few.

The most important cause of vaccine failure in young animals is the inability of an antigen to impart immunologic memory whether or not passive maternal antibodies are present. Vaccine failures also can occur when the immune response is suppressed, eg : in heavily parasitized or malnourished animals (such animals should not be vaccinated). Stress, including pregnancy, extremes of cold and heat and fatigue or malnourishment, may reduce a normal immune response, probably due to increased glucocorticoid production.