Ticks are not only annoying parasites, but also dangerous carriers of pathogens. Among the numerous tick-borne diseases, the most prominent are Lyme disease, anaplasmosis, babesiosis and Ehrlichiosis. But while awareness of the risks of these diseases increases, critical factors in assessing the risk of transmission are often overlooked.

Distribution and activity time of ticks

The distribution and activity of ticks play a crucial role in the transmission of pathogens. The most widespread tick species in Germany is the common wood tick (Ixodes ricinus). These ticks are active at temperatures of around 10°C and are mainly active in the months of March, April and September. Their preferred habitats are forests, forest edges, tall grass and fallow areas. The common woodbuck transmits the dangerous pathogens of Lyme borreliosis (pathogen: Borrelia burgdorferi also Borrelia) , anaplasmosis (pathogen: Anaplasma phagocytophilum also anaplasma) and TBE (tick-borne encephalitis) (pathogen: arboviruses).

The riparian forest tick (Dermacentor reticulatus) can be found in the eastern and southwestern parts of Germany. It is particularly active in sunny areas with bushes or trees and is different from other tick species. It transmits babesiosis (pathogen: Babesia canis) and its activity period even extends over the cold months of January and February.

The brown dog tick (Rhipicephalus sanguineus) originally comes from Africa and has found its way to the Mediterranean countries and occasionally to Germany. It is mainly found in heated homes and transmits babesiosis, anaplasmosis and Ehrlichiosis.

Diseases caused by tick infestation

Lyme disease: Diverse symptoms and transmission rates

Lyme disease appears in different forms in dogs. The acute form often begins with an inflammatory swelling of the injection site and a ring-shaped redness of the skin around it. Within 10 days of the tick bite, the following symptoms may occur:

• Fever, skin inflammation
• Lameness
• Joint and muscle inflammation
• neurological disorders

Sometimes the Borrelia infection goes unnoticed by the owner and only develops after weeks or months. This can range from fever attacks to general well-being impairments to disturbances in nervous functions and paralysis.

Around 35% of common woodbucks carry Lyme disease pathogens. Interestingly, it is estimated that around two thirds of dogs in Germany are infected with Borrelia and develop symptoms.

It is important to note that the detection of Borrelia antibodies in the blood alone does not necessarily indicate Lyme disease, as clinical symptoms may be absent. Any dog ​​that has already had contact with Borrelia and has a healthy immune system produces antibodies and can overcome a Borrelia infection without medical help.

The transmission time is approximately 24 hours, so timely removal of an infected tick can prevent transmission and infection.

Anaplasmosis: On the rise and yet mysterious

Canine anaplasmosis is caused by bacteria of the genus Anaplasma. When the disease breaks out, it manifests itself in altered blood counts with low blood platelets and anemia. Typical symptoms include sudden fever, fatigue, apathy, enlarged spleen and liver, malaise, loss of appetite, and joint inflammation and swelling. Fortunately, canine anaplasmosis is curable if detected and treated early.

In their book "Anaplasmosis in dogs - infection common, disease rare" Michele Bergmann and Katrin Hartmann describe that in Germany around 1/3 to 1/5 of all dogs have antibodies against canine anaplasmosis.

About 4% of common woodbucks carry these pathogens. Transmission of the pathogen requires the tick to adhere to the host for approximately 36-48 hours. This provides an opportunity to prevent infection by quickly removing the ticks.

Tick-borne encephalitis (TBE) in dogs

Tick-borne encephalitis, or TBE for short, is a tick-borne disease. While it rarely or never occurs in dogs, it represents a significant health risk for humans and is even classified as a reportable disease in some regions.

Babesiosis: Canine malaria and its effects

The riparian forest tick carries the babesiosis pathogen, also known as canine malaria. This disease leads to the destruction of red blood cells and can therefore cause more or less severe anemia. Symptoms appear approximately 1 to 3 weeks after the tick bite and vary widely. They range from non-specific general disorders, fever, apathy, red-colored urine to central nervous system disorders and shortness of breath. The dog's individual immune defense plays a crucial role here. Dogs from Mediterranean countries have fewer problems with this disease due to natural resistance to babesiosis pathogens.

Dogs living in Germany need medical support in the event of a serious, acute infection after, for example, a vacation in southern Europe. The severe symptoms of the acute phase of babesiosis are obvious to the owner. Warnings of untreated progression, which can be fatal, should be taken seriously.

According to statistics in the German Veterinary Journal from 3/2007, a total of 313 domestic dogs were diagnosed with babesiosis in a period of 2 years (2005 + 2006), proven by the PCR test. This equates to around 150 dogs per year. Based on the estimated number of around 10 million dogs living in Germany, the percentage of proven babesiosis cases is only 0.0015%.

The exact rate of riparian forest ticks infected with babesiosis pathogens has apparently not yet been researched. This species of tick is relatively new in our latitudes and is not as common everywhere as the common wood tick. It concentrates on certain local areas where it occurs more frequently, sometimes in nests. (Source: www.zecken-radar.de )

The transmission time of the babesiosis pathogen by the alluvial forest tick is around 48-72 hours, while www.parasitosen.de states a period of 12-72 hours depending on the activity level of the tick.

Ehrlichiosis: A problem for dogs from Mediterranean countries

Ehrlichiosis primarily affects dogs in or from Mediterranean countries and is not a major problem for domestic dogs. Symptoms of the acute phase of this disease include fever, vomiting, diarrhea, and bleeding from the nose and gums.

Since the occurrence of the brown dog tick is rather rare in Germany and not every one of these ticks necessarily carries Ehrlichiosis (Ehrlichia canis) or babesiosis pathogens, an infection is rather unusual in our regions. This is also confirmed by the University of Hohenheim, as can be read in an interview with Katrin Fachet on Tasso.net. There is reference to a small number of 2 ticks in 2018 and around 10 ticks in the following year throughout Germany.

Dog's natural defenses

In terms of evolutionary history, wolves and dogs have always fought against parasites and therefore have natural defenses against pathogens. A strong immune system can provide an appropriate immune response to pathogens such as Borrelia, Babesia and Anaplasma. A healthy immune system produces antibodies when the dog comes into contact with pathogens and can thus ward off symptoms of illness.

The fact that most dogs can handle ticks without any problems shows that they are capable of dealing with a normal tick infestation. Only a small number of dogs show symptoms such as fatigue, loss of appetite and nervous disorders. These dogs often react negatively to chemical repellents because these do not prevent the tick from biting. Increased awareness of tick control and removal of ticks is important to prevent transmission of pathogens.

Conclusion: active protection and mindfulness

Ticks transmit dangerous pathogens to dogs that can cause serious health problems. A comprehensive understanding of the distribution and activity of ticks as well as how long the pathogens are transmitted is crucial to minimizing the risk. Both chemical and natural repellents have their advantages and disadvantages, but regular tick inspection and timely tick removal are essential. A strong dog immune system can play a crucial role in warding off disease.