New case of babesiosis in the UK

A new case of babesiosis, a malaria-like tick-borne parasitic disease caused by infection with Babesia, on an untravelled dog was confirmed in the UK last month and has sparked a renewed warning to pet owners that Essex and surrounding counties should be treated in the same way as a foreign country.

 The disease was confirmed on a single dog in Ware, Hertfordshire. The location is only a few miles from where the UK’s first outbreaks of babesiosis in untravelled dogs were found in 2016 prompting questions as to whether the outbreaks are connected and if the tick D reticulatus is spreading. The dogs’ signs in this most recent case included its urine being dark red in colour.

 Hannah Newbury of the Big Tick Project team said: “This case is a reminder of the value of vets remaining vigilant to the possibility of babesiosis being present in dogs that have not travelled outside of the UK or had contact with dogs that have. It also highlights the needs for more open discussions around parasite risk to ensure dogs are given regular tick treatments throughout the year to reduce the risk to pets and owners”.

It comes as a reminder to everyone that regular checks for ticks when back from an outing / walk with pets is really important.  You can find out more about how to check for ticks on our page.

 Babesia in your Pet

Babesia invades the dog’s red blood cells. Until recently, reports of Babesia were generally only seen in pets returning to the UK under the PETS travel scheme as the ticks responsible in the UK did not carry the disease. However, in both 2016 and 2017 there have been cases seen in the South East of England in pets that have no history of travel. 

Signs of Babesia include pale gums, a temperature and being generally ‘unwell’.  Other signs can include blood in the urine and jaundice.  On examination and blood testing, your vet may find other clinical signs including enlarged lymph nodes and spleen as well as anaemia. The severity of the disease can vary greatly from mild disease through to organ failure and death.

Babesia in Cats

Cats can get infested with ticks just as dogs can. The organism that caused the Babesia cases in untravelled dogs in the South East of England in 2016 were due to Babesia canis.  Clinical signs of babesiosis in cats is thought not to occur in Europe1

 As a vet what are you looking for that can raise your suspicion of Babesia?

Babesia signs and symptoms

Canine babesiosis is a tick-borne disease caused by several species of a parasite that invade the dogs’ red blood cells.  In the UK, the ticks needed to transmit the disease were largely considered to be absent meaning that until recently, clinical cases were sporadic and generally restricted to animals returning to the UK under the PETS travel scheme. In February 2016, three cases of babesiosis were seen in one Essex Veterinary practice during the preceeding three months in dogs that had not travelled abroad. All the affected dogs were exercised in a common area of uncultivated park. Subsequently, a tick from one of the affected dogs was identified as Dermacentor reticulatus, and was shown to be carrying B. canis2.

Clinical signs

The clinical signs of Babesia are primarily due to haemolytic anaemia or secondary complications. Babesia canis is characterised by fever, pale mucous membrane, anorexia, lethargy anaemia, jaundice enlarged lymph nodes and spleen. Clinical signs of Babesia vogeli tend to be more mild to moderate although severe forms are seen in puppies   The severity of babesiosis varies from sub clinical infection to extensive organ failure and death. 

Diagnosis of Babesiosis include history and clinical signs alongside peripheral blood smears to identify the babesia pyroplasms within the red blood cells.  PCR can be performed and is highly sensitive but results can take a number of days. 



1. Davies S, Abdullah S, Helps C, Tasker S, Newbury H, Wall R. Prevalence of ticks and tick-borne pathogens: Babesia and Borrelia species in ticks infesting cats of Great Britain. Veterinary Parasitology. Volume 244, 15 September 2017, Pages 129-135

2. Phipps LP, Fernandez De Marco MDM, Hernández-Triana LM, Johnson N, et al. Babesia canis detected in dogs and associated ticks from Essex. Vet Rec. 2016;178:243–244.



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