Ticks in autumn: are they still active and how to protect your pet?

This is general information, not veterinary advice. If your pet is unwell or has a tick you cannot remove safely, call a vet.

What the sources say about autumn activity

The sources do not fully agree on when the season ends. That is not a contradiction, but a difference in what and where they measured.

The European Scientific Counsel Companion Animal Parasites (ESCCAP) describes in its ectoparasite guideline that tick activity is highly seasonal and that in the UK and central Europe there are typically two peaks. For Slovenia, the national Administration for Food Safety, Veterinary Sector and Plant Protection (UVHVVR) says the tick season runs from early spring to autumn.

The German–Austrian study by Probst, Springer and Strube (2023) collected ticks removed from dogs and cats by veterinary practices every month from May 2020 to June 2021: 19,514 ticks in total, of which 10,287 from dogs and 8,005 from cats. Between December 2020 and February 2021 the practices received an average of 108 Dermacentor reticulatus and 70 Ixodes ricinus ticks per month. The authors link winter activity to unusually mild winters and consider the traditional April-to-October protection period outdated.

Note the limitation: the study covers Germany and Austria. We did not find a Slovenian or Croatian study of winter tick activity on dogs and cats, so for our region we can only say that ticks have not disappeared by autumn.

Which ticks and diseases matter

Among the common ticks in Slovenia UVHVVR lists the sheep tick (Ixodes ricinus), the brown dog tick (Rhipicephalus sanguineus) and Dermacentor reticulatus, and warns that ticks like tall grass, undergrowth and shrubs. Among diseases of dogs and cats it names borreliosis, anaplasmosis and babesiosis.

Babesiosis is of particular interest in autumn because in our region it is carried by Dermacentor reticulatus, which the review by Bajer et al. (2022) calls one of the fastest-spreading tick species in central and north-eastern Europe. The same review reports that among 81 symptomatic dogs in Croatia Babesia canis was identified in 78 (96%), and that of 238 dogs admitted to a clinic in Ljubljana in 2000–2002, 14 (5.9%) were infected with Babesia. These figures are old and are not today's prevalence, but they show the disease is not an exception in the region. In Hungarian data from the same review, clinical cases peaked in March–April and October–November. UVHVVR adds that babesiosis involves mainly ticks from north-eastern Slovenia and Croatia and that signs can recur in cycles.

UVHVVR also states that infection generally requires the tick to be attached for at least 24 hours. That is not a safe margin for waiting: ESCCAP and the Veterinary Faculty in Ljubljana advise removing the tick as soon as it is found.

What to do after a walk

Found one tick? ESCCAP warns that you may not find every tick, especially larvae, nymphs and unengorged adults, so tick protection for the rest of the season may be worth considering for every animal in the household.

How long to protect your pet

ESCCAP says protection should cover the whole period in which ticks are active. The decision depends on risk:

In its second row ESCCAP adds that in warmer areas and where ticks survive in houses or shelters protection may be needed all year. Dermacentor reticulatus has been seen questing in winter in Germany. As we found no Slovenian or Croatian data on winter activity, work out with your vet how much your pet is out in nature and choose a product for them. Prevention also means avoiding tall grass and shrubs where ticks wait (UVHVVR, MSD).

Signs that disease may have started

• fever, apathy or marked tiredness;
• pale gums and mucous membranes (UVHVVR, Veterinary Faculty);
• brown or dark orange urine and yellowish mucous membranes in babesiosis (Veterinary Faculty);
• recurring limping (borreliosis, UVHVVR);
• vomiting or diarrhoea with fever (anaplasmosis, UVHVVR);
• a red or swollen bite site (MSD).

Frequently asked questions

Do I need to protect my pet from ticks in winter too?

ESCCAP advises protection across the whole period in which ticks are active, and all year round where there is ongoing or high disease-transmission risk. The German and Austrian authors (Probst et al., 2023) recommend year-round use of licensed products. As we found no winter data for Slovenia or Croatia, decide about the cold months with your vet, based on how much your pet is out in nature.

Do cats need tick protection?

Cats get ticks too: UVHVVR recommends checking a cat daily. ESCCAP says cats appear less affected by tick-borne diseases than dogs, but that ticks on cats should be controlled with a suitable product. Highly concentrated synthetic pyrethroids registered for dogs only are toxic to cats, so never use a dog product on a cat.

Can I remove a tick with oil or my fingers?

No. The MSD Manual advises tweezers close to the skin and gentle pulling, never bare hands. ESCCAP explicitly warns against oil, alcohol and ether. The Veterinary Faculty in Ljubljana stresses that excessive handling of the tick increases the chance of disease transmission, so remove it gently and straight away.

How long must a tick be attached to pass on disease?

UVHVVR states that infection generally requires at least 24 hours of attachment. The Veterinary Faculty in Ljubljana stresses that the chance of transmission depends on attachment time, and ESCCAP advises immediate removal. So 24 hours is not a time you may wait: remove the tick as soon as you find it and watch your pet.

I removed the tick and my pet looks healthy. Is that enough?

Not necessarily. ESCCAP warns that pathogens may already have been transmitted and that signs can appear later. UVHVVR advises taking the animal to a vet quickly if it shows signs of illness during tick season. Note the bite date, watch appetite, behaviour, gums and urine, and tell your vet the animal had a tick.