Ticks are the arthropods that can transport more bacteria, viruses and parasites to people and animals. In addition, they can also transmit paralyzing toxins through their saliva after a sting. The recurrent deworming of our dogs and cats is very important, since they can also transmit zoonotic diseases that can pass to people. Likewise, the risk of being close to them must be taken into account, mainly in the favorable months of the year, since our animals can develop an allergic reaction to their bite.
Curious about how many diseases ticks can carry? In this article on our site we will deal with the infectious diseases that these external parasites transmit to our beloved dogs and cats, as well as those that can be transmitted to people.
Why can ticks transmit disease?
Ticks, in addition to being the largest mites, are hematophagous external parasites that feed on the blood of animals and people, and it is precisely when they are feeding that they can transmit disease-causing pathogens, as well as release with their saliva a powerful paralytic toxin that produces ascending muscle relaxation without fever, pain, exhaustion, and shortness of breath. The latter occurs mainly in cats, dogs and children.
Diseases that ticks transmit to people
The diseases that ticks transmit to people can be more or less serious, so it is important to know them, learn to identify them, go to the doctor as soon as possible and keep our animals dewormed.
Ricketsiosis
Rickettsiae are bacteria that act as obligate intracellular parasites. Those transmitted by ticks belong to the group of spotted fevers that tend to produce similar symptoms due to their tropism of blood vessels:
- Rocky Mountain Spotted Fever: Caused by Rickettsia rickettsii, is characterized by fever, malaise, muscle and headache pain, chills, conjunctival hyperemia (redness), and a maculopapular rash on the extremities that spreads rapidly to much of the body. It is a disease unique to the United States and Central and South America.
- Mediterranean spotted fever: the causal agent is Rickettsia conorii and the dog tick (Rhipicephalus sanguineus) is the main vector of the disease, characterized by high fever, malaise, formation of a papule that turns into a painless blackish necrotic area and only occasionally causes itching. It usually heals without sequelae, but sometimes it produces severe forms and death in up to 2.5% of those infected.
- African tick-bite fever: caused by Rickettsia africae, is generally mild, with little tendency to present complications and skin rash less than the diseases mentioned above.
- Debonel or tibola: this is an emerging disease in Europe that can be caused by Rickettsia slovaca, R.raoultii or R. rioja. It is transmitted by ticks of the Dermacentor genus, characterized by the presence of a necrotic eschar on the skin of the scalp, accompanied by painful lymphadenopathy in the cervical area.
Borreliosis
Also called Lyme disease, is the most common tick-borne infectious disease in the United States and Europe, carried by the Ixodes tick ricinus, which is infected by the spirochete Borrelia burgdorferi. The main symptom is a erythema migrans that begins as a spreading red papule accompanied by malaise, neck stiffness, fever and lymphadenopathy. As the disease progresses, more erythema migrans, meningoencephalitis, myocarditis, and tachycardia occur. Arthritis attacks of large joints can occur for several years.
Babesiosis
Caused in people by Babesia duncani, B. divergens, and B. microti, which infect red blood cells Although it usually causes mild symptoms, muscle pain, fatigue due to hemolytic anemia (due to the rupture of red blood cells by Babesia), jaundice, liver and spleen enlargement, muscle pain, nausea and vomiting, and emotional instability may occur.
Colorado Tick Fever
The causative agent in this case is a virus transmitted primarily by Dermacentor andersoni (Rocky Mountain tick). Anyone can get the disease if they are in areas of the western United States and Canada at elevations above 5,000 feet in the Rocky Mountains. The main symptoms are fever, vomiting, nausea, headache and eye pain, lethargy and sensitivity to light.
Tularemia
Ticks can transmit their causal agent, Francisella tularensis, a bacteria that is very resistant in the environment. Tularemia can be of several types: glandular, ulceroglandular, oculoglandular, oropharyngeal, pulmonary, or typhoid. If transmitted by the bite of these vectors, an ulcer occurs in the area of the bite with pain in the lymph nodes, fever, headache and exhaustion.
Tick-Caused Encephalitis
This is a nervous disease of viral origin, caused by a flavivirus transmitted by Ixodes ricinus ticks, producing meningitis, encephalitis, meningoencephalitis or meningoencephalorradiculitis, which can cause sequelae in most of those infected.
Crimean-Congo hemorrhagic fever
It affects more than 30 countries in Africa, the Middle East, Asia and Western Europe, with a growing incidence in recent years in Europe. It is caused by a nairovirus and transmitted by ticks of the genus Hyalomma. The symptoms are fever, muscle pain, headache, neck stiffness, eye irritation and hypersensitivity to light, depression, small hemorrhages in the mouth, throat and skin that can lead to larger hemorrhages.
Anaplasmosis and Ehrlichiosis
Anaplasmosis is a disease transmitted by Ixodes ricinus and caused by Anaplasma phagocytophilum and ehrlichiosis is caused by Ehrlichia bacteria and transmitted by the lone star tick (Amblyomma americanum). Both diseases produce similar symptoms: fever, chills, muscle aches, weakness, headache, nausea and/or vomiting; being able to cause a generalized coagulation of the blood (disseminated intravascular coagulation), organ damage, convulsions and coma. Ehrlichioses can also cause rashes on the torso, legs, and arms.
Diseases that ticks transmit to dogs and cats
Many of the diseases listed above are considered zoonoses, meaning they can be transmitted from dogs and cats to people. Thus, the diseases transmitted by ticks do not necessarily have to reach people through their direct bite. Let's see, next, the diseases that affect dogs and cats:
Canine erhlichiosis
Caused by Erhlichia canis and transmitted by the tick Rhipicephalus sanguineus. It is a bacterium that affects the white cells of the canine immune system, specifically the monocytes and lymphocytesIn the acute phase there is fever, anorexia, depression, lymphadenopathy and enlarged spleen, hemorrhages, uveitis, vomiting, lameness or pain due to polyarthritis, gait disturbances and respiratory distress.
Sometimes the disease progresses to a chronic form in which cells produced in the bone marrow are decreased (pancytopenia). In other cases, the disease produces a more severe form with a worse prognosis where symptoms such as weakness, depression, pale mucous membranes, edema, kidney and/or liver failure and neurological signs appear.
Anaplasmosis
There are two types of anaplasma that can develop into anaplasmosis in dogs and cats:
- Transmitted by Ixodes ricinus, Anaplasma phagocytophilum causes damage to white blood cells and fever, joint and muscle pain appear due to the arthritis it produces in our cats and dogs.
- Anaplasma platys (canine infectious thrombocytopenia), transmitted by the tick Rhipicephalus sanguineus, affects canine platelets causing a drop in their count total and resulting in hemorrhages of different sizes and locations.
Lyme's desease
Occurs, as in humans, by the bacterium Borrelia burgdorferi and the vector Ixodes ricinus and Ixodes scapularis, and can cause fever, intermittent lameness, arthritis and, in more serious cases, kidney damage due to immune-mediated glomerulonephritis, arrhythmias or nervous disorders.
Babesiosis
This disease transmitted by ticks to dogs and cats is caused by protozoa of the genus Babesia: B canis (transmitted by Dermacentor reticulatus), B. Rossi, B. vogeli (transmitted by Rhipicephalus sanguineus), B. bigemina, B. gibsoni (transmitted by Rhipicephalus sanguineus), B. conradae, B. microti-like (transmitted by Ixodes hexagonus). It is a parasite that, as in people, attacks canine red blood cells causing symptoms derived from hemolysis or breakage: weakness, anemia, jaundice, fever, anorexia, pale mucous membranes, lymphadenopathy, enlarged spleen and decreased number of platelets that can lead to more serious complications such as acute renal failure, liver damage, disseminated intravascular coagulation and multiple organ failure. In cats it can cause lethargy, anorexia, weakness and diarrhoea.
They can also transmit parasitic roundworms called filariae: Dipetalonema dracunculoides (affects the peritoneum), Dipetalonema reconditum and Acanthocheilonema grassii (affects muscle fascia), but most dogs and cats have no symptoms.
Feline infectious anemia
It is caused by small bacteria sitting on the edge of the red blood cells: Mycoplasma haemofelis or Candidatus Mycoplasma haemominutum, Candidatus Mycoplasma turicensis and Candidatus Mycoplasma haematoparvum. They can produce subclinical to severe anemia depending on the mycoplasma that affects our feline, so that Mycoplasma haemofelis is the most pathogenic, capable of producing severe anemia with a large drop in hematocrit (or the volume of red blood cells in the body's total blood), leaving cats depressed, anorexic, with an enlarged spleen and of the liver, fever, and increased heart and respiratory rate.
It can also affect dogs (Mycoplasma haemocanis and Candidatus Mycoplasma haematoparvum), but to a lesser extent and they only produce symptoms if their spleen has been removed or they are under constant stress.
Hepatozoonosis
Hepatozoon canis and Hepatozoon americanum only affect dogs, transmitted by ingestion of the Rhipicephalus sanguineus tick. In most cases it is mild or subclinical, with fever, anemia or emaciation observed in young or immunocompromised animals. Many dogs also have purulent oculo-nasal discharge, muscle stiffness and, when affected by Hepatozoon americanum, pain in the limbs and lower back. When the infection is chronic, renal amyloid can be deposited, causing glomerulonephritis. Cats can be affected by other types of hepatozoon with subclinical infection.
Bartonellosis
Bartonella henselae affects cats, is transmitted by fleas, but is also believed to be transmitted by ticks. It is the cause of "cat scratch disease" in people. Cats generally present subclinical infections, but in some cases they present fever, nephritis, myocarditis, neurological alterations, muscular pains or reproductive alterations.
Viral encephalitis
Virosis caused by a flavivirus described in the group of human diseases, which can also affect our dogs and cats in which it produces fever and neurological signs.
Mediterranean spotted fever
Rickettsia ricketsii is endemic in America, while R. conorii and R. slovaca are transmitted in Spain, causing mild infection sometimes accompanied by lethargy. R. ricketsii can produce acute clinical signs in dogs, which are more predisposed to infection than cats, producing fever, anorexia, lymphadenopathy, polyarthritis, cough, abdominal pain, vomiting, diarrhea and edema of the extremities. In severe cases, mucosal hemorrhages appear.
Citauxzoonosis
C.felis, a protozoan of the Theileriidae family that affects felines, causes symptoms only in domestic cats, producing a acute symptoms of dehydration, jaundice, fever, anorexia and lethargy with high mortality.
Tularemia
It affects cats more than dogs due to the transmission of the bacteria that causes the disease (Francisella tularensis). It is a rare disease, less controlled rural or hunting dogs may be affected with fever, anorexia, muscle aches, nasal and eye discharge, and occasionally, abscesses at the point of infection. Cats manifest fever, anorexia, apathy and ulcers on the tongue and palate.
How to avoid tick-borne diseases?
Given the seriousness of many of the diseases transmitted by ticks, both to animals and people, it is essential to carry out a good prevention plan. Thus, we recommend:
- Avoid wooded areas or areas with tall grass, especially from spring to autumn, which are the times when These parasites proliferate. It is recommended, in case of visiting these areas, to wear white and long clothes, since this way we can better see if we have any ticks.
- Examine our dogs and cats for ticks, as well as their correct dewormingat the veterinary center. See How often to deworm a dog and don't miss the video below about deworming cats.
- Use insect repellants such as DEET or 0.5% permethrin.
- Remove ticks from our body or that of our animals correctly with tweezers, that is, by pulling it as far as close to the skin as possible and outwards, applying constant pressure to remove it completely so that the head does not remain inside the skin. In case of doubt, it is preferable to go to a veterinary or medical center.
