Rickettsial diseases are those caused by rickettsia, microscopic organisms that are not quite bacteria and not quite viruses. In dogs, the most common rickettsial diseases are ehrlichiosis, Lyme disease, and Rocky Mountain spotted fever. The rickettsial organisms that cause each of these diseases are carried by ticks and transmitted to the pet within 24 hours after the tick bites and attaches to the pet. Tick control is useful to decrease the spread of these diseases. Rickettsial diseases are zoonotic, meaning they can be transmitted to people. However, an infected pet can only transmit the disease to a person through a tick bite and not be directly infecting the person itself. Tick control is therefore important to decrease the chance of spreading the disease to the pet owner as well.

Clinical signs vary with the specific disease
Ehrlichiosis. Clinical signs are varied and may include fever, lack of appetite, anemia (pale gums), decreased platelet count, weight loss, abdominal pain, enlarged lymph nodes, enlarged spleen, difficulty breathing, swollen joints, eye abnormalities (blindness, redness, cloudiness of the cornea), discharge from the eyes, and diarrhea.

Lyme Disease. Clinical signs can include swollen and painful joints, enlarged lymph nodes, fever, change in personality, and seizures.

Rocky Mountain Spotted Fever. Clinical signs are varied and are almost identical to those seen in dogs with ehrlichiosis. The signs may include fever, lack of appetite, anemia (pale gums), decreased platelet count, weight loss, abdominal pain, enlarged lymph nodes, enlarged spleen, difficulty breathing, swollen joints, eye abnormalities (blindness, redness, cloudiness of the cornea), discharge from the eyes, and diarrhea.

Principal Natural Treatments for Rickettsial Diseases

Omega-3 Fatty Acids – eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) – are derived from fish oils of coldwater fish (salmon, trout, or menhaden fish) and flaxseed. Omega-6 fatty acids – linoleic acid (LA) and gamma-linolenic acid (GLA) – are derived from the oils of seeds such as evening primrose, black currant, and borage. Often, fatty acids are added to the diet with other supplements to attain an additive effect.

Just how do the fatty acids work to help in controlling inflammation in pets? Cell membranes contain phospholipids. When membrane injury occurs, an enzyme acts on the phospholipids in the cell membranes to produce fatty acids including arachidonic acid (an omega-6 fatty acid) and eicosapentaenoic acid (an omega-3 fatty acid). Furthermore metabolism of the arachidonic acid and eicosapentaenoic acid by additional enzymes (the lipoxygenase and cyclooxygenase pathways) yields the production of chemicals called eicosanoids. The eicosanoids produced by metabolism of arachidonic acid are pro-inflammatory and cause inflammation, suppress the immune system, and cause platelets to aggregate and clot; the eicosanoids produced by metabolism of eicosapentaenoic acid are non-inflammatory, not immunosuppressive, and help inhibit platelets from clotting. There is some overlap and the actual biochemical pathway is a bit more complicated than I have suggested here. For example, one of the by-products of omega-6 fatty acid metabolism is Prostaglandin E1, which is anti-inflammatory. This is one reason why some research has shown that using certain omega-6 fatty acids can also act to limit inflammation.

Supplementation of the diet with omega-3 fatty acids works in this biochemical reaction. By providing extra amounts of these non-inflammatory compounds, we try to overwhelm the body with the production of non-inflammatory eicosanoids. Therefore, since the same enzymes metabolize both omega-3 and omega-6 fatty acids, and since metabolism of the omega-6 fatty acids tend to cause inflammation (with the exception of Prostaglandin E1 by metabolism of omega-6 as mentioned above), by supplying a large amount of omega-3 fatty acids we favor the production of non-inflammatory chemicals.

Many disorders are due to overproduction of the eicosanoids responsible for producing inflammation. Fatty acid supplementation may be beneficial in inflammatory disorders by regulating the eicosanoid production.

In general, the products of omega-3 (specifically EPA) and one omega-6 fatty acid (DGLA) are less inflammatory than the products of arachidonic acid (another omega 6). By changing dietary fatty acid consumption, we can change eicosanoid production right at the cellular level and try to modify (decrease) inflammation within the body. By producing the proper (anti-inflammatory) fatty acids, we can use fatty acids as an anti-inflammatory substance. However, since the products of omega-6 fatty acid metabolism (specially arachidonic acid) are not the sole cause of the inflammation, fatty acid therapy is rarely effective as the sole therapy but is used as an adjunct therapy to achieve an additive effect.

Note: Flaxseed oil is a popular source of alpha-linoleic acid (ALA), and omega-3 fatty acid that is ultimately converted to EPA and DHA. However, many species of pets (probably including dogs) and some people cannot convert ALA to these other more active non-inflammatory omega-3 fatty acids. In one study in people, flaxseed oil was ineffective in reducing symptoms or raising levels of EPA and DHA. While flaxseed oil has been suggested as a less smelly substitute for fish oil, there is no evidence that it is effective when used for the same therapeutic purposes as fish oil. Therefore, supplementation with EPA and DHA is important, and this is the reason flaxseed oil is not recommended as the sole fatty acid supplement for pets. Flaxseed oil can be used to provide ALA and as a coat conditioner.

Dosages
What is the best dose to use in the treatment of pets? Most doctors use anywhere from two to ten times the label dose. Research in the treatment of allergies indicates that the label dose is ineffective; higher doses may also be indicated in pets with rickettsial diseases. In people, the dosage that showed effectiveness in many studies were 1.4 to 2.8 gm of GLA per day, or 1.7 gm of EPA and 0.9 gm of DHA per day, which is hard for people to obtain from the supplements currently available.

If this were shown to be the correct dosage for pets, a 50-pound dog would need to take 10 or more fatty acid capsules per day to obtain a similar dosage, depending upon which supplement was used. Therefore, while the studies with omega-3 fatty acids show many potential health benefits, it is almost impossible to administer the large number of capsules needed to approximate the dosage used in these studies. The best that owners can hope for is to work with their veterinarians and try to increase, the amount of omega-3 fatty acids in the diet to get the preferred ratio of 5:1, omega-6 to omega-3 fatty acids. (Research on pets with atopic dermatitis suggests this is the ideal dietary ratio.)

There are diets constructed with this "ideal" ratio. For owners who do not like giving their pets medication, or for those pets who don't take the supplements easily, it might be wise to try some of these medically formulated diets, available from your pet's doctor, that contain the fatty acids. However, because these medicated diets may not be as natural as desired, holistic pet owners may prefer other options.