Ehrlichia is a type of Rickettsia which is transmitted by the saliva of the tick “Riphincephalus” and produces clustering in the cells called morulas. This produces a bleeding and bruising similar to that of the Rickettsia. There are several different types of Ehrilichias that will produce the illness, but the E.Canis is the most common and the one that causes the worst illness.
On the contrary to the Rickettsias this bacteria is not transmitted to the tick’s young, it is only contagious by ticks that have taken blood from an animal in acute phase of the illness.
The acute stage is between 1 -3 weeks after the transmission from the tick and lasts several weeks. This phase usually occurs in spring – summer when the ticks are most active. Symptoms include fever, loss of appetite and weight, nasal and ocular secretion, breathing difficulties, bruising and signs of bleeding.
Afterwards comes the “subclinic” phase, in which the animals are carriers of the illness but do not present symptoms, this can last for months. Some animals eliminate the infection during this period, but it is not common.
Generally, infected dogs pass on to the chronic stage in which the organism remains in the cells and can produce a great variety of symptoms like bruising, bleeding and a deficit of platelets.
A blood test will give us important information to direct us to the diagnostic, but it is important to make an antibody re-count against Ehrlichia, which can be variable in the acute phase and is positive in the subclinic and chronic phases.
If there are clear clinical signs and positive blood results, treatment must be started. The treatment in dogs that have positive blood results but no symptoms can be given to prevent the progression of the illness, although it does not prevent re-infection.
Treatment consists in alleviating the effects caused by the illness, by giving antibiotics and in some cases, corticoides. The recommended antibiotic is Doxiciclina during 28 – 30 days, the symptoms usually disappear in a short time. Other treatment consists in injecting dipropionato de imidocarb twice, separated by 14 days.
To check that there is an improvement after treatment, it is recommended to mainly check the symptoms, because the antibody title does not decrease straight away, this can take months or even years to prove negative again, or can even stay positive all their lives.
The prognostic for dogs in the acute phase is good, but reserved in the chronic phase because of the affected immune system and lack of reaction to treatment.
It is a good idea to have a yearly blood test carried out. The illness can also be transmitted through blood transfusions, so it is important to have regular checks done on donor animals.
The best way to prevent this illness is to keep check on the actual ticks, as has been explained in the case of infection by Rickettsia, although in this case elimination is slightly easier.
Cats, although not very frequently, can be affected by Ehlrichia Canis. Symptoms being similar of those of dogs, blood tests and response to treatment will confirm the presence of the illness. The treatment is similar to that of dogs.