It has been in the news that some dogs in Essex have been infected with Babesia Canis and become very ill. This is news because these dogs had not travelled outside the UK, and Babesia had not previously been endemic in the UK, although commonly occurring in Europe.
What is Babesiosis?
Babesiosis is a tick borne disease which causes destruction of red blood cells resulting in anaemia and jaundice. Acutely affected dogs appear depressed, weak and are disinclined to eat (anorexic). They have pale membranes (e.g. lips, eye lids or tongue) and often have a fever. The passing of very dark coloured urine is also frequently noted. The disease cannot be passed directly from one animal to another. It is only spread by bites from ticks infected with the protozoan (one celled) parasite, Babesia.
Babesiosis is common in many parts of the world including large parts of Southern Europe.
What is the cause of the disease?
The disease is caused by protozoan (single celled) organisms. Babesia canis is the most common type and is the variety diagnosed in Essex.
How does Babesiosis spread?
The parasite cannot survive outside the dog or the tick vector. The tick implicated in the cases in Essex is Dermacentor reticulatus. This tick is variously named the ornate dog tick, ornate cow tick, meadow tick or marsh tick, reflecting its variety of habitats. In Europe it is found up to 1,000m above sea level on grasslands, pastures, fringes of meadows, and grassy paths in woodlands, along rivers and streams, banks of ponds, in marshy areas and peat bogs. It has been described in the sand dune systems and coastal pastures of West Wales and South-West England, particularly North Devon. It has recently been found in coastal South-East Essex presumed transported by sheep moved from Wales and would seem to be spreading in the UK and in Europe. It is currently not found in our area but is likely to spread this way in time.
Can we catch Babesiosis?
Unlike some other tick borne diseases (e.g. Lymes disease – Borreliosis), Babesia canis does not appear to be transmissible to man, in other words it is not a zoonotic disease. Some other Babesia varieties (Babesia gibsoni) can cause disease in humans and cats but this has not yet been diagnosed in the UK.
Is the disease very common?
Canine Babesiosis has an almost worldwide distribution. It has always been prevalent in Southern Europe and appears to be spreading northwards across France and Germany. The disease occurs commonly in endemic areas. In these areas, animals develop some inherent immunity so the disease is more common in young or debilitated animals.
Is it important in Britain?
Until relatively recently Babesiosis was unknown in Britain except with animals in quarantine. Relaxation of quarantine regulations with the introduction of the PETS scheme in 2000, resulted in the death of an elderly dog as a result of the disease after a visit to Southern Europe. In subsequent years there have been several other cases confirmed in Britain in animals which have travelled. These cases in Essex are the first where the animals have not travelled outside the UK.
The disease is presently restricted to a small, well defined area in Essex, but now that it has entered the UK, it is likely to spread further.
Dogs in the UK have never been exposed to Babesiosis and will have no inherent immunity, and are more likely to be susceptible to contracting the disease if bitten by an infected tick.
Will I know if my dog has been infected?
If your dog has become infected, there may be no signs for 10-20 days, (i.e. during the incubation period). Signs can vary from slight malaise (being a bit ‘off colour’) to serious haemolytic disease with lack of appetite, dark coloured urine, multi-organ failure and even death in 24-48 hours. Some very mild cases may recover without treatment but may still be carrying the parasite and act as carriers. The danger lies in the fact that certain ticks already resident in Britain may prove vectors for the spread of the disease from such animals.
Is there any treatment?
Drugs are available which are very effective provided a correct diagnosis can be arrived at without delay. The disease is quickly diagnosed by doing a blood smear and finding the parasite in the red blood cells. Blood smears can be done in house to speed diagnosis. Chronic carriers can be diagnosed by serology or PCR. If your dog shows any signs of lethargy, pallor, jaundice or dark coloured urine, it is important that you consult your veterinary surgeon without delay as Babesiosis generally responds well to treatment if caught early, but can be life threatening if treatment is delayed.
Is there anything that can be done to prevent my dog becoming infected?
Babesia is only transmitted by the bite from infected ticks. Ticks are not able to transmit infection immediately upon first attachment. They need a period of 24-48 hours of initial feeding before the organisms are able to cross into your dog. This means that using effective tick control that repels ticks to prevent them from biting, or kills them within 24 hours is a very effective means of preventing the disease. There are a wide variety of effective tick control methods, including collars, spot-ons and tablets. Please talk to us find the best method for your pet. If you notice a tick on your dog, it should be removed immediately, using a tick removal tool.
Dermacentor reticulatus Ornate dog tick, Ornate cow tick, Meadow tick, Marsh tick.