Unless you’ve been living under a rock, you’ve probably heard of West Nile Virus. The virus was first isolated in 1937 from a woman living in the West Nile District in Uganda, but wasn’t reported in the Western Hemisphere until 1999. Since then, it has received extensive media coverage, often making it sound worse than it really is.

The Facts

Now don’t get me wrong; West Nile Virus is capable of causing illness and in some cases death. But to give you an idea of the prevalence of the virus in the United States, here are some facts: In 2007, 3510 people were infected with WNV (that?s 1 in every 100,000 people). Only 3% of these cases were fatal. That means last year people in the U.S. had a 0.00003% chance of dying from West Nile Virus. You have a greater chance of being struck by lightning (0.0001%).

The Basics of West Nile Virus: Transmission

West Nile Virus is a flavivirus, transmitted by over 30 species of mosquito. Humans can get the virus from blood transfusions, organ transplants, through the placenta, breast milk, and most commonly mosquito bites. However, just because a human is infected with the virus doesn?t mean they?ll present any symptoms or feel ill. If symptoms do occur, they usually do so from 3 to 14 days after first becoming infected.

Symptoms

The majority of those presenting symptoms will feel much like they have the flu, with fatigue, vomiting, fever, muscle aches, and loss of appetite. In less than 1% of cases, more severe symptoms are present, including high fever, stiffness in the neck, tremors, convulsion, disorientation, severe headache, or coma. There is no treatment for West Nile Virus since it is a virus and is so uncommon (makes vaccine development difficult).

WNV in Pets

Most animals are even more unlikely to become ill from West Nile Virus. Those animals most at risk include horses and birds. Old, young, or otherwise immunocompromised cats and dogs are also more likely to become ill from WNV, but cases are rare. In fact, since 1999 there has been only one dog and one cat case of death from WNV.

Pets who have become ill from WNV exhibit such symptoms as decreased appetite, depression, disorientation, tremors, unusual head posture, circling, and convulsions. However, there is no need to euthanize a pet infected with WNV as the virus is currently incapable of animal-to-animal transmission (including humans).

Preventing WNV in Me and My Pets

The bottom line in prevention of West Nile Virus is prevention of mosquitoes and mosquito bites. You can decrease the amount of mosquitoes in your area by eliminating sources of standing water in which mosquitoes breed (tires, bird baths, cans, ceramic pots, etc), cleaning gutters at least once a year to prevent clogging, turning over things like wheel barrows that may collect rainwater, and properly chlorinating swimming pools and hot tubs.

You can also lower you and your pet?s risks of getting bitten by staying indoors in the early morning and evening when mosquitoes are most active. Mosquito repellents can be used to keep mosquitoes away, but be careful which kinds you use. Use only mild repellants (no DEET) on animals and check with your veterinarian before using if you?re not sure of a repellent?s safety.

http://www.prb.org/
http://www.usatoday.com/weather/resources/basics/wlightning.htm
http://www.cdc.gov/ncidod/dvbid/westnile/surv&controlCaseCount07_detailed.htm
http://www.health.state.ny.us/nysdoh/westnile/education/2746.htm
http://www.urbanext.uiuc.edu/westnile/pets.html
http://dogs.about.com/cs/travel/a/camping.htm
http://www.healthypet.com/library_view.aspx?ID=43&sid=3

The Immune System: General Overview

The immune system of your pet provides the required levels of protection for the detection and destruction of foreign agents within the body systems. The identification of foreign materials is essential for the prevention of diseases caused by pathogens. The immune system functions in such a manner as to distinguish foreign materials from the organisms own materials.

Autoimmunity: Definition

The disorder of autoimmunity is caused by certain abnormalities or malfunctions in normal immune system functioning. The term “auto” is derived from the meaning of “self” and immunity refers to the immune system. These abnormalities leave the immune system incapable of distinguishing between foreign and self materials. Autoimmunity is typically associated with an overactive immune system that identifies self materials as foreign, destroying healthy self cells.

Autoimmunity: Diseases

There are a variety of diseases within the category of autoimmune disorders. Provided below is a short list of some of these diseases that shows the variableness associated with autoimmune disorders.

• Graves disease: Thyroid disease known for causing hyperthyroidism. It is caused by the immune system mistakenly attacking the thyroid gland, increasing overall hormone production.
• Diabetes (Type 1): Autoimmune disorder that attacks the pancreas, disrupting the normal rates of insulin production.
• Systemic Lupus: Highly variable autoimmune disorder that is not limited to specific areas/organs of the body.
• Multiple Sclerosis (MS): Autoimmune disorder that attacks the myelin sheath located responsible for the insulation of neurons.
• Rheumatoid Arthritis: Autoimmune disorder that attacks joints.
• Vitiligo: Associated as an autoimmune disorder due to its common presence with such diseases. Causes skin pigmentation changes.
• Pernicious Anemia: Autoimmune disorder that attacks and decreases the number of red blood cells.

Autoimmunity: Causes

The exact causes of autoimmune disorders have yet to be identified. There is a strong correlation between genetic affiliations and the development of autoimmune disorders. The presence of a family history of autoimmune diseases is associated with an overall increased risk. General immune system health is another important factor. All immune systems have nutritional requirements to ensure proper functioning. Certain drugs are correlated with increased risk for development of specific autoimmune disorders.

Environmental factors are also in consideration as causes, including specific chemicals, physical and infectious agents. There is currently a lack of scientific evidence to support further theories of autoimmune disease development, but research continues daily in an attempt to further define causes and treatments.

Autoimmunity: Symptoms

There are several symptoms associated with autoimmune disorders. Symptoms are variable based on the individual animal and the specific autoimmune disease.

• Fatigue
• Fever
• Cough
• Wheezing
• Rash
• Diarrhea
• Joint pain
• Haemoptysis: Coughing blood

Autoimmunity: Treatments

Treatment options for autoimmune disorders are fairly limited due to the lack of information and scientific evidence of exact causes. The specific treatment is based on the particular autoimmune disorder, as autoimmune disorders are highly variable and can attack almost all parts of the body. Treatments are associated with different rates of success. It is important to consult your veterinarian for treatment options and proper diagnosis.

http://www.peteducation.com/article.cfm?cls=1&cat=1352&articleid=236
http://www.peteducation.com/article.cfm?cls=2&articleid=957

Cat Immune Systems: General Overview

The manner in which your cat’s complex immune system functions is particularly similar to your own immune system. The immune system encompasses all of the body’s defense mechanisms. It is a surveillance system responsible for the detection, identification, and elimination of harmful foreign objects. A vast and essential entity within the body, the immune system is divided into two specific branches, the innate and adaptive immune systems, based on certain characteristics.

The Innate Immune System

The innate immune system is non-specific. It is the body’s first and foremost defense mechanism against foreign objects. It is not able to adapt, but is designed to keep the body safe by maintaining a general destruction and avoidance mode for all things foreign. Some examples of the innate immune system include:

• Skin
• Respiratory mucous
• Stomach acid

The Adaptive Immune System

The adaptive immune system is specific. It is adaptive, and educates itself to remember and recognize specific foreign invaders. Maximum efficiency of the adaptive immune system occurs upon immediate recognition of foreign objects that have been committed to memory due to an accelerated response. The adaptive immune system is activated if the innate immune system can not terminate or successfully impede the foreign invader.

The Immune System: Cell Types

The immune system is immense and requires several specific cell types in order to ensure the safety of the body. Immune system cells develop and mature in the bone marrow, but differentiate in distinct manners, creating unique cell types.

Monocytes

Upon maturation, monocytes exit the bone marrow and enter the bloodstream. Monocytes are generally located within the bloodstream and mature into macrophages. Monocytes function to protect the body through a process called phagocytosis. Phagocytosis is the mechanism used to capture, ingest, and eradicate any foreign invaders detected.

Macrophages

Macrophages mature from monocytes and are typically located within specific tissues within the body. Macrophages also function to destroy foreign invaders through the particular method of phagocytosis. Imperative to a healthy adaptive immune system, macrophages are also responsible for the removal of antigens for presentation to T-cells.

Lymphocytes: B and T Cells

T-cells, also known as “memory cells,” are produced in the thymus and function to regulate and promote the adaptive immune system. There are several subsets of T-cells all having specific functions and are activated through very complex mechanistic processes. T-cells survive infection and commit to memory the specific antigens from the invading foreign object. This memory allows for the macrophages to be more effective in their identification and elimination of foreign objects.

B-cells also have many subsets and have a complex maturation pathway. They are responsible for the production and distribution of antibodies for the eradication of foreign objects. In order for B-cells to produce antibodies, T-cells must activate the B-cells and present the specific antigen to which the antibody must be produced. Each T-cell is responsible for the memory of one specific antigen, just as one B-cell is responsible for the production of one specific antibody.

Antigens

Antigens are unique proteins, localized to the outside of foreign objects that upon recognition causes stimulation of the immune response. It is these specific antigens that provide the memory to the T-cells promoting accelerated response paths for quicker destruction of pathogens.
http://www.peteducation.com/article.cfm?articleid=956
http://www.petplace.com/cats/structure-and-function-of-the-immune-system-in-cats/page1.aspx

The Immune System: Structure and Function

The immune system is a line of defense against harmful agents. There are two types of this immune system, innate and adaptive. Innate systems are typically nonspecific, and all animals have them, barring medical abnormalities. Adaptive systems are just that, adaptive. They have the ability to change over time with exposure to specific conditions and environments.

The Immune System: Innate Defense Systems

The first line of this defense system for your dog is nonspecific, keeping everything out, and is the same as your first line of defense, the skin. In addition, all entrances have nonspecific defense systems including stomach acid, respiratory mucous, and specific chemicals located in the saliva. There are cells located throughout the body of your dog known as phagocytes, nonspecific foreign object eliminators. This line of defense is constantly at work, but is not capable of keeping out all foreign invaders. Due to this fact, your dog has a second system for defense purposes.

The Immune System: Adaptive Defense Systems

The adaptive immune system differs from innate in the fact that it is specific and only activated upon need. Adaptive defense systems are particular to specific foreign objects that enter the body. The adaptive defense system will readily attack any foreign object that enters your dog’s body for destruction. This system has a complex memory system, achieved through the use of specific antigens, and readily activates to destroy foreign invaders recognized. Part of this system is inherited from birth, and others parts are developed throughout the dog?s life cycle, including exposure to specific conditions and vaccinations.

The Importance of the Food Your Dog Eats

The food you give your dog should encapsulate several necessary obligations. The food should provide all of the nutrients required by the body. Dog foods are available that fulfill this purpose and the federal drug administration ensures that proper requirements are fulfilled. Dog treats are also typically produced in such a manner as to taste satisfactory to the animal while providing nutritional supplementation. Problems are usually confronted when the dog is exposed to ‘people foods’ that should not be included commonly in the diet.

Immune System Necessities for Optimum Activity: Diets that Damage

As is true for all systems, the immune system has specific requirements for optimum activity. The food eaten should provide all the necessary nutrients for the proper functioning of all systems, including the immune system. The immune system is important for the overall health of your dog, and providing the necessary nutrients is essential. Not providing these nutrients, or over providing your dog with unnecessary treats can damage overall immune system health. The immune system has several key requirements ensuring proper function and overall health including:

• Selenium: Prohibits fat oxidation and aids in the prevention of the production of free radicals.
• Potassium: Ensures proper kidney function through fluid maintenance and the balancing of electrolytes.
• Iron: Found prevalently in blood, is required for the production and maintenance of myoglobin and hemoglobin, responsible for oxygen delivery.

Sources:
http://www.peteducation.com/article.cfm?cls=2&cat=1614&articleid=957
http://www.webmd.com/cold-and-flu/features/using-your-immune-system-to-stay-well