Tick Season is Upon Us!
Ticks are a group of parasitic arachnid species similar to spiders, scorpions and mites that range between 0.5 - 11mm in size, depending on the lifecycle. Ticks survive by feeding off mainly bird and mammal hosts such as farm animals, wildlife, our cats and dogs, and us humans. As well as causing irritation on the skin when feeding, they are a source of transmission of diseases that can be fatal in some situations. As the world is warming up, and travelling between countries becomes easier, some new and emerging diseases are entering the UK, and as such, we need to be more aware of these critters.
The female tick tends to be the most noticeable on our pets as they grow the most when feeding to provide energy to produce up to 3,000 eggs.
Tick infestations are usually seasonal in the UK between March and June, and again from August to November, but there is still a risk of picking them up all year round. There are over 12 species of ticks present in the UK, but there are 3 that are more likely to attach to our pets: Ixodes ricinus (Sheep tick), Ixodes hexagonus (Hedgehog tick), and Ixodes canisuga (Fox tick).
Since June 2013, Larkmead has been collecting ticks to help Public Health England, along with researchers at Bristol University to identify populations of tick species around the UK and the diseases that they could potentially carry and transmit. The most common tick that we have identified (88.6% of ticks analysed) is I. hexagonus and is known to be found in many different types of environments, ranging from forests, caves, above 1800m to more urban settings like back gardens. This species is the most common tick found on cats and the second most common tick found on dogs. I. ricinus accounts for 11% of our ticks collected and is found mainly in areas of rough grazing, moorland, woodland and areas when wild deer and rabbit are in abundance. The fox tick, I. canisuga makes up the remaining 0.4% of the collected ticks and can be found in large kennelling facilities. A fourth tick, Dermacentor reticulatus is located mainly in wooded areas across Western Europe, however it is found in certain coastal areas within the UK (West coast and South East coast of England), and has increased in numbers as mentioned in the press recently after transmitting the disease Babesiosis around areas of Essex. This tick has not been picked up in the Oxford area currently.
Babesia is parasite that invades mainly dogs, and rarely cats’ red blood cells, replicates inside those cells, then bursting out ready to infect other cells. This process, along with the host’s immune system trying to destroy infected cells causes anaemia through the lack of working red blood cells. The animal becomes jaundiced, anorexic, produces red urine, and can develop kidney failure. The disease can be fatal. Treatment involves chemotherapy medications for a number of weeks. This disease does not spread to humans.
Ticks are also well known for playing a part in the transmission of the bacteria Borrelia burgdorferi that causes Lyme disease that affects both dogs and humans. In rare cases, cats have also been affected by the disease. In dogs, the clinical signs can range from having a general discomfort, fever, or lameness; to swollen lymph nodes, painful swollen joints and kidney disease. As there is no specific clinical sign to diagnose Lyme disease, it can be hard to diagnose; treatment is with a long course of antibiotic and pain relief medications.
Detecting and Removing Ticks
Ticks sit on the end of grass blades and detect carbon dioxide and heat of the host. They then hold on to the animal’s fur as the host brushes through the long grass. If the skin is suitable, the tick will bury its mouthparts under the surface host’s skin, which is usually over the host’s face and ears, chest and front legs. As cats are regular self-groomers, they can sometimes be quick to groom them out, but can still be visible in areas that the cats miss, eg inside the ear flaps. You can distinguish a tick from a mass or wart by looking at the base of the tick to just see a narrow attachment and the parasite’s legs above the skin.
The host animal will detect the presence of the tick in the first few hours after attachment and put up an immune defence, clotting the blood which the tick is feeding from and can result in areas of swelling and localised pain. The tick counteracts the host’s clotting defence by releasing saliva with a number of anticoagulants and proteins, and also possible infectious organisms like the protozoa babesia and the bacteria-causing Lyme disease. This is why it is important to remove or kill the tick with anti-parasitic treatment within approximately 24-48 hrs of initial feeding. However, tick removal should not be delayed if you spot a tick before that time.
Tick removers are by far the safest and easiest equipment to use to remove ticks and are relatively inexpensive to purchase. Please do not use tweezers to remove ticks as putting pressure on the tick’s body can release saliva into your animal increasing the risk of spread of any disease they may carry. Pulling on the tick can also risk leaving the mouthpart in the skin, causing an abscess to develop in time.
Prevention in Dogs
A number of products are licenced to treat against Ixodes and Dermacentor species, and also a common European tick Rhipicephalus sanguineus. These are available in a spot-on or collar form. Each product takes different length of time to kill the tick, or prevent attachment - please discuss options with your vet. You should not use treatments meant for dogs on cats as these can be lethal.
Prevention in Cats
Note: Do not use dog treatments on your cat, as these are lethal to cats
As less is known about tick-borne diseases in cats, and following on from the successful campaign last year in dogs, The Big Tick Project 2016 will focus on a nationwide collection of ticks from cats to track tick species and numbers, and aid in the detection of new and emerging diseases in cats.
For more information, or if your pet has a tick, please pop in to one of our practices for advice and the opportunity to participate in the scheme.