“Don’t forget the dog’s pesticide”! If there were 10 commandments for a master, this would probably be in the top three.
Why is it so important? We often forget that the real problem is not the actual parasites, but the innumerable diseases they can transmit, sometimes even to humans.
One of these is thecanine ehrlichiosis: an endemic disease in the Mediterranean basin. What does it mean? That every tick that bites our pet can potentially transmit this disease to him.
What is canine ehrlichiosis?
Ehrlichia in dogs is a bacterial disease transmitted by ticks, the main symptoms of which are fever persistent and anemia. The bacterium in question enters dogs through salivary secretions during the bite of an infected tick.
It is also known by other names:
- Canine tropical pancytopeniadue to its tropical origin;
- Canine monocytic diseasebecause it preferentially attacks the animal’s mononuclear leukocytes, a type of White blood cells.
When we talk about canine Ehrlichiosis, we almost always refer to the bacterium Ehrlichia caniswhich however is not the only strain capable of triggering the disease.
Types of Dog Ehrlichia
The term “Ehrlichiosis” refers to a set of bacterial microorganisms belonging to the order of Rickettsialesresponsible for different types of infections (such as rickettsiosis).
Those of greatest interest, capable of provoking Ehrlichia in dogs and humans I am:
- E. dog;
- E. chaffensis;
- E. ewingii.
The first type is present all over the world, including Europe. The tick capable of transmitting it is in fact well rooted in our territory: the brown dog tick (Rhipicephalus sanguineus).
The other 2 they are not present in Italybut are of particular interest outside the European borders, in some areas of the American continent.
Ehrlichiosis is therefore a zoonosis: even humans can become infected following a tick bite.
The endemic areas of canine Ehrlichiosis
In Europe, the distribution ofE. dog follows the geographical distribution of brown tick: this is why we find it in temperate climate areas, especially in the Mediterranean basin.
The countries with the highest rate of infections are:
- France,
- Italy (largest in the south),
- Spain,
- Portugal,
- Greece
- Bulgaria.
Although this tick predominantly strikes in the spring, disease symptoms can appear throughout the year due to the variable incubation times associated with the bacterium.
Symptoms of ehrlichiosis in dogs
The symptoms of dog ehrlichiosis can vary greatly depending on the health of the animal. Since it is a bacterial infection, immunosuppressed dogs or dogs that have developed concomitant infections have a more complex pathological course.
Also there race it can affect the severity of the infections: in the German Shepherd, for reasons that are still unknown, the infection is generally more serious.
However, there are also many cases where Ehrlichia in dogs heals spontaneously. However, relapse and chronicity are not infrequent, especially in asymptomatic subjects. The evolution of symptoms varies according to the different stages of the disease.
Acute phase
It is the first stage of infection, which lasts 2-4 weeks. Here you can find symptoms in dogs such as:
- Fever,
- lethargy,
- Anorexia,
- Weight loss.
These generalized symptoms are often associated with a increased secretions (serous or purulent) nasal and ocular. When you are at this point, the symptoms may pass as well unnoticed to the owner.
Most dogs with good immune systems are able to fight off the infection effectively, without the need for treatment. If not, the disease progresses to the next stage.
subclinical phase
The subclinical phase is characterized by permanence of the bacterium in the host. It is the most insidious of the disease: it can last for months or even years without any manifest symptoms.
During this stage, theE. dog it “stabilises” in the cells of the dog’s splenic reticuloendothelial system, a particular mechanism of the immune system. The bacterium can resist by bypassing the antibody response and making itself “invisible” to antibodies. The only sign that can be seen at this stage is a lack of platelets in the blood (thrombocytopenia).
Chronic stage
The chronic phase may be characterized by the same nonspecific symptoms as the acute phase. These can evolve into a more serious form, which can also lead to death of the dog.
In addition to the non-specific symptoms already mentioned, the following may appear at this time:
- Haemorrhagic manifestations: (nosebleeds, urine and faeces, haemorrhagic petechiae);
- Eye disorders: uveitis, retinal detachment, corneal opacity;
- Cough and wheezing (irregular breathing);
- Neurological manifestations: paresis, convulsions, difficulty moving (ataxia).
Ehrlichia lameness
As for the presence of lameness associated with canine ehrlichiosis, it may result from a suppurative polyarthritis that develops only following infections from E. ewingii.
As already specified, this strain is absent in the Italian territory. The most plausible explanation is that there are co-infections with other arthropod-borne diseases, such as Borreliosis or l’Anaplasmosi.
Canine Ehrlichiosis Diagnosis
The first diagnostic approach consists in evaluating the probability that the dog has been bitten by a tick, in a rather variable period of time.
At the same time, the blood tests. Definite diagnosis requires more extensive investigations, such as serologic testing for Ehrlichiosis.
Canine ehrlichia test
Through serological tests, such as direct immunofluorescence (IFA) or ELISA, infection can be detected between 7 and 28 days after its onset. However, in the acute phase the test could show false negatives: for this reason it is preferable to repeat it after about 2-3 weeks.
ELISA kits are also commercially available for the detection of antibodies toE. dog. With PCR, on the other hand, it is possible to identify the DNA of the pathogen.
Blood count test
From a blood sample, in the case of dog Ehrlichiosis, it will be possible to highlight:
- Thrombocytopenia;
- Anemia;
- White blood cell count outside the reference range.
Other common abnormalities involve the biochemistry profile, with hypoalbuminemia, proteinuria, and increased alkaline phosphatase activity.
Treatment of canine ehrlichiosis
Treatment of canine ehrlichiosis consists of the administration of broad-spectrum antibiotics, such as doxycyclinebelonging to the tetracycline class.
The cure is 10 mg/Kg/day administered orally for at least 28 days. In less complex cases, improvements can already be seen in the first 24-48 hours after the first administration.
In case of chronicitythe dog may not respond adequately: in that case alternative drugs can be tried.
If your dog is in a serious condition from the pathogen, supportive care, such as blood transfusions or intravenous fluid administration, may be required.
Once again the most powerful weapon is prevention. It’s not just about the health of our animals, but ours too. The dog represents a potential reservoir for these infectious agents, carrying ticks and other possible vectors in domestic environments.
Taking care of it in the right way eliminates this risk: never forget the pesticide for your dog, all year round!