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By Susan Starchuk Of the 800+ species of ticks so far discovered, about 100 have proven to transmit disease to humans and animals. They are second only to mosquitoes in that distinction. Ticks carry and transmit pathogens such as rickettsaie, bacteria, protozoa, viruses, nematodes, and toxins. It has also been proven that one tick bite can transmit multiple pathogens. In North America they are: Lyme disease, Ehrlichiosis, Babesiosis, Relapsing Fever, Rocky Mountain Spotted Fever, Colorado Tick Fever, Bartonella, Tularemia, Q-Fever, Tick-Borne Encephalitis and Tick-Borne Paralysis. In 2001, viral meningitis was found to co-infect with Lyme disease. All may present singly or as co-infections. Co-infections can be problematic to diagnose due to an overlapping of symptoms. It is known that co-infections may heighten the severity and duration of illness. Research suggests that a wide range of testing is needed when a tick-borne illness is suspected or when confirmed illness does not respond to treatment. RELAPSING FEVER TULAREMIA EHRLICHIOSIS BABESIOSIS ROCKY MOUNTAIN SPOTTED FEVER COLORADO TICK FEVER Q FEVER BARTONELLA RELAPSING FEVER. Relapsing Fever is transmitted by body lice or a soft tick that feeds for only 10 to 90 minutes, thus infecting quickly. Ticks are of concern in the Western Hemisphere, where it is caused by the spirochete Borrelia hermsii. Reported cases are often in clusters, as with groups of campers in rustic cabins that are infested with rodents on which ticks feed. Tick-borne Relapsing Fever has been found in the western US and Canada, particularly BC. The protein produced by B. burgdorferi, (Lyme disease) during feeding and transmission is closely related to the protein produced by B. hermsii during infection of its' tick vector. Characterized by sudden onset of high fever, Relapsing Fever is detected in the blood only when fever is present and is not detectable when temperature is normal. The spirochete has 40 or more genes, which permit a shift of outer surface proteins. Now undetectable by body cells, a new clone is able to avoid destruction by the antibodies produced to destroy the original organism. Thus, the patient improves temporarily until the new clone multiplies sufficiently to cause a relapse. The relapses distinguish B. hermsii from other diseases. Tick-borne disease tends to have an average of 3 relapses (up to 10), each lasting 3 to 11 days (average 7-8). Untreated B. hermsii has a mortality rate of 4-10%; treated early, the rate decreases to less than 1%. Patients who present the complications are at a higher risk. Symptoms present within 2 weeks of infection. Symptoms:
References: Relapsing Fever (Tick-borne) Tick-borne Diseases: Relapsing Fever Tick-borne Relapsing Fever in North America Medlineplus-Relapsing Fever -scroll to Medlineplus Encyclopedia: Relapsing Fever Relapsing fever mimicking Lyme disease Author Unknown New Relapsing Fever Group Spirochete Found  Relapsing Fever–Like Spirochetes Infecting European Vector Tick of Lyme Disease Agent More information on co-infections Return to top: CO-INFECTIONS TULAREMIA. Tularemia, also called Rabbit fever, is caused by the bacteria, Francisella tularensis. It is found world wide in 100 species of animals, birds and insects. The primary vectors are rabbits and ticks. There has been a shift from being known as a winter disease to a summer disease, indicating more infection as a result of tick exposure. The majority of cases are undiagnosed or not reported. In BC there were 3 CDC confirmed cases up until 1997. There is a 5% mortality rate in untreated cases and 1% in treated cases. Incubation time is an average of 3-4 days (up to 14 days) before the onset of symptoms. Symptoms:
Tularemia is treated with antibiotics. A vaccine is available for those at high risk (trappers, hunters and lab workers). References: Tularemia emedicine.com Tularemia nih.gov/medlineplus More information on co-infections Return to top: CO-INFECTIONS EHRLICHIOSIS. Ehrlichiosis is a tick-borne disease of the ehrlichia family. Human monocytic ehrlichia (HME) is caused by Ehrlichia chaffeensis. Human granulocytic ehrlichia (HGE) is caused by Ehrlichia phagocytophilia. Ehrlichia ewingii, was recognized in 1999, having infected 4 patients in the lower mid US. Another specie exists in Japan and Malaysia. Ehrlichia can be difficult to diagnose, therefore a clinical diagnosis may be necessary, especially if co-infected with Lyme disease. Duration of illness is not documented yet and symptoms can vary considerably, ranging from a mild illness to a severe, life-threatening condition. The mortality rate with HME is 2-5%, whereas with HGE the death rate is 7-10%. The symptoms, which present in 7-9 days (up to 21 days), are similar for all species. Symptoms:
As a co-infection Ehrlichia may require a longer treatment time. It is also known that Ehrlichia may reactivate, stressing the need for treatment as soon as possible. References: Another Disease Brought to You by Ticks lymedisease.org Tick-Borne Diseases, Ehrlichiosis emedicine.com Ehrlichiosis cdc.gov Diagnostic Hints and Treatment Guidelines for Lyme and Other Tick-Borne Illnesses ilads.org/burrascano Ehrlichia in Moose and Deer. Norway More information on co-infections Return to top: CO-INFECTIONS BABESIOSIS There are 100 species of Babesiosis worldwide that infect mammals, but only a few infect humans. Babesiosis is a protozoan malaria-like infection which invades the blood cells. The European genus, B. divergens (B. bovis cattle species) is responsible for a 42% mortality rate in France and Great Britain. The majority of Europeans who are known to have contracted Babesiosis have had their spleens removed (asplenic), therefore being more vulnerable to infection. The North American genus, B. microti, carries a 5% mortality rate. The highest rate of infections comes from the Northeastern and Midwestern states, where it has been found to infect up to 66% of Lyme disease patients. Several documented cases of Babesiosis have been contracted from blood transfusions as a result of blood donors being unaware they are carriers. In the last few years two variant species have emerged in the US. MO1, in Missouri, is probably distinct from the European B. divergens, but the two share several characteristics. B. sp .WA1, was identified in Washington state. The patient was healthy and had a spleen. A strain in California, CA1, infected 6 patients. A study of the first 4 cases showed all were without spleens. Two of the cases were complicated; a third patient died. Analysis showed that all 4 cases were identical and more closely related to a canine genus (B. gibsoni) than any other Babesia genus. Serum from 3 of the cases was reactive to WA1. Serologic surveys suggest the infrequency of recognized cases may underestimate the true risk of B.sp.WA1. It is now a distinct possibility that B.sp.WA1 is a present risk in BC. There is evidence that co-infected Lyme and Babesiosis may increase the number of symptoms, severity and duration of illness. It is possible that immunologic interactions occur within Lyme disease transmission that result in a higher number of Lyme disease spirochetes. Babesiosis is self-limiting and mild in most people and usually resolves on its' own. Therefore it is often under-diagnosed and unreported. Prolonged recovery, complications and/or death are more likely in persons who are: without spleens, over 50 or immune-suppressed. Babesiosis can last a few weeks or up to 18 months. Relapses can occur for up to 27 months after the first episode. Patients may carry the pathogen even when all symptoms are resolved. Untreated infection can last months or years. Babesiosis presents symptoms 1 - 9 weeks after infection, in some cases up to 3 months. Symptoms:
Sporadic cases have been reported of transmission to infants before or after birth. Children's infections are described as moderate to severe, usually less so than in adult infection. References: Babesiosis- by the American Lyme Disease Foundation Babesiosis: The latest tick-borne danger Diagnostic Hints and Treatment Guidelines for Lyme and Other Tick-borne Illnesses Journal of Infectious Diseases 1997; 175(6):1432-9 Sonoma County Dept. of Health Services Ticks & Human Babesiosis When to Suspect & How to Monitor Babesiosis (search Babesiosis) More information on co-infections Return to top: CO-INFECTIONS ROCKY MOUNTAIN SPOTTED FEVER. Rocky Mountain Spotted Fever, is caused by the bacteria Rickettsia rickettsii. Limited to the Western Hemisphere, it is the most severe and commonly reported illness from the Rickettsia family in the US. It can be difficult to diagnose in the early stages and can be fatal without prompt treatment. It is believed the 3-5% mortality rate reflects the numbers of patients who do not exhibit the signature rash, therefore not receiving early treatment. RMSF presents symptoms about 1 week after infection (range of 3-12 days). Symptoms:
References: Rocky Mountain Spotted Fever cdc.gov emedicine.com merk.com More information on co-infections Return to top: CO-INFECTIONS COLORADO TICK FEVER Colorado Tick Fever is a virus restricted to North America, primarily in the Rocky Mountains and Pacific coast including BC and Alberta. As it is mainly found in areas above 4,000 feet, it mostly infects young adult males, reflecting exposure through occupational or recreational activities undertaken at that altitude. The numbers of cases likely represents only a small fraction of infections, as reporting is not mandatory. Many cases likely remain undiagnosed or unproven. There is no evidence of person-to- person infection but there have been rare cases of blood transmission from blood transfusions. Not a dangerous disease, it is usually self-limiting though it may stay in the blood as long as four months. Prompt recovery is the norm. Incubation time from infection to onset of symptoms is 4-5 days (up to 20 days). Symptoms:
References: state.ut.us lyme.org (click diseases) emedicine.com Medlineplus Medical Encylopedia More information on co-infections Return to top: CO-INFECTIONS Q FEVER. Q fever ("Q" for query), was first discovered in Australia in the 1930's and is now a world wide illness. It is caused by Coxiella burnetti which belongs to the rickettsial family of organisms. Though infection is possible from farm animals and their by-products (such as hides, dust or raw milk), it is now recognized as a possible pathogen in co-infection. Q fever does not present with any distinctive or characteristic symptoms. It has been found that specific geographical areas may present a dominant symptom, such as respiratory complications or hepatitis. Acute Q fever is generally self-limiting; in one study, only 4% of patients required hospitalization. Chronic Q fever is more difficult to treat and can be fatal. However, this is rare and tends to be prevalent in older patients. Symptoms: Acute Q fever:
Chronic Q Fever: Endocarditis (inflammation of the inner lining of the heart) is the most common problem of chronic Q fever. It can occur months to years after the acute infection. Other symptoms include fever, fatigue, shortness of breath and rash. Q fever is treated with antibiotics. References: emedicine.com More information on co-infections Return to top: CO-INFECTIONS BARTONELLA. Of the 16 species in the Bartonella family, at least 8 are known to infect humans. Bartonella henselae, a tick-borne specie, was previously called Cat Scratch Fever as it was believed it could only be contracted from the scratch or bite of a cat that had been infected by a flea. Recent studies have shown that in California, 19% of ticks were positive for the bacteria, 85% in North Carolina, and 20%in New Jersey. These percentages of infected ticks are higher than ticks infected with Borrelia burgdorferi, the cause of Lyme disease. The infection rate in the US has jumped from 6 cases per 100,000 persons to 10 per 100,000. Bartonella is a worldwide disease. B. henselae is closely related to B. quintana. Known as Trench Fever during the First World War, B. quintana is still of concern in the Western Hemisphere. A louse-borne pathogen, it is a problem with those who are homeless, drug or alcohol addicted, living under poor hygienic conditions. Bartonella is normally mild and self-limiting in healthy people but can cause severe problems in those who are co-infected or immuno-suppressed. Fatalities have been documented. Even as a primary infection there can be wide differences in severity and clinical presentations, due to the amount of inoculum and variations in strain virulence. Bartonella incubates in 3-10 days, the range of symptoms varying with the severity of infection. Early treatment is believed to reduce the possibility of disseminated (wide-spread) complications. Symptoms:
Mild cases resolve without treatment. More severe infections require treatment with antibiotics, a different protocol than that used for Lyme disease. The disease may last weeks to months References: CBS Health Watch:"Bartonella Transmissible in CA Ticks" emedicine.com Archives of Neurology 2001 Sep; 58 (9): 1357-63 "Of Fleas & Ticks on Cats & Mice"ama-assn.org Bartonella Bartonellosis More information on co-infections Return to top: CO-INFECTIONS The Silent Pandemic | Osteoarthritis | Fibromyalgia | Research | BC News | Brucellosis | Links | Contact |