Ticks, Fleas and Worms | Cairn Terrier Luxembourg

What your puppy has had here

Worming: on the standard puppy schedule. The dates and products are on the worming record in your puppy pack.
Flea and tick products: none. We do not use chemical flea or tick treatments on our dogs. The common tablets and many spot-ons and collars work by attacking the parasite's nervous system. The official product information lists rare nervous-system side effects in dogs (see "What the products do" below).

Below are the facts as the official sources give them, including the points where the experts recommend more than we do. The decision for your dog is yours. Talk it through with your vet.

Ticks

Which ticks, and when

In northern Europe most ticks found on dogs are the castor bean tick (Ixodes ricinus).¹ The ornate dog tick (Dermacentor reticulatus) has been in Luxembourg since at least 2015. It was first recorded in Wellenstein.⁴ It is the tick that carries canine babesiosis.¹

Luxembourg's Ministry of Health says ticks are active from February to November.³ The ornate dog tick can also be active in mild winter weather. A German study found both species on dogs all year round.⁵

The diseases that matter here

Babesiosis (from the ornate dog tick) is moderate to severe and can cause fatal kidney failure.^1,2 Infected ticks have been found in Belgium and the Netherlands, where dogs have died of it.⁷ We found no published count of cases in Luxembourg dogs.
Lyme disease: 11.3% of castor bean ticks tested in Luxembourg carried the bacteria.⁸ Most infected dogs never show signs. Fewer than 5% of dogs suspected of having Lyme disease actually have it.²
Anaplasmosis occurs throughout Europe and is often mild.¹ 1.9% of Luxembourg ticks tested carried it.⁸
Tick-borne encephalitis (TBE): none of about 4,500 ticks collected across Luxembourg in 2025 carried the virus, and no case caught in Luxembourg has been reported.⁹ It is rare in dogs.¹
Ehrlichiosis is found in southern Europe. It is a risk when you travel there.²

How long a tick must bite before it passes on a disease

This is why a check after every walk helps. Most diseases only pass once the tick has fed for some time.

Disease	Usual time	Fastest reported
Lyme disease	16–48 h	About half of test animals infected after 17 h^2,3,10
Babesiosis	24–48 h	8 h, from male ticks that had already fed^2,11
Anaplasmosis	24–48 h	No faster time found²
Ehrlichiosis (travel)	hours	3 h¹²
TBE	minutes	About 15 min¹³

The daily check

ESCCAP advises checking dogs every day during tick season and removing any ticks as soon as you find them.¹ Ticks prefer these spots:¹

Face and lips
Ears, inside and out
Armpits
Between the toes
Groin
Around the tail and bottom

A Cairn's harsh coat hides ticks well. Part the coat with your fingers and feel for small bumps, especially after walks through long grass, hedges and the edges of woods.

Removing a tick

Use a tick hook or tick tweezers, as close to the skin as possible.¹
Pull slowly and steadily, or turn gently if the tool's instructions say so. Luxembourg's Ministry of Health advises turning gently. The US Centers for Disease Control (CDC) advises pulling straight without twisting.^3,14
Do not put oil, alcohol, nail polish or heat on the tick first.^1,14
Write down the date. If your dog falls ill in the following weeks, tell the vet about the tick.

See a vet the same day if, after a tick bite, your dog has

tiredness, fever or loss of appetite
dark red-brown urine, or pale or yellow gums
sudden lameness, nosebleeds or tiny bleeding spots on the skin

Babesiosis shows 1–3 weeks after the bite and needs treatment at once. In a German study of 49 sick dogs, 7 died or were put to sleep.^2,15

Where the experts differ ESCCAP accepts checking and removing ticks by hand as enough tick control for low-risk dogs. For dogs that go outdoors regularly, and especially where babesiosis occurs, it recommends a tick product for the whole tick season.¹ No study has shown that daily checks prevent disease in dogs, and checks cannot beat the fastest diseases in the table above.

What the products do

So that you can weigh it up yourself, here is what the official product information says.

Tablets (the "-laner" group)

They work from inside the dog. The EU product information says the tick must attach and start feeding before the drug reaches it, and that the risk of passing on disease "cannot be completely excluded".^16,17
They kill castor bean ticks within about 8–12 hours of attaching, and ornate dog ticks within 48 hours.^16,17 In the manufacturers' own trials, treated dogs did not catch babesiosis or Lyme disease.¹⁸
Side effects: in 2018 the US Food and Drug Administration (FDA) warned that this group can cause muscle tremors, unsteadiness and seizures, including in dogs that had never had a seizure. It also said the products are safe for most animals.¹⁹ The EU product information lists these side effects as very rare (fewer than 1 in 10,000 dogs) and advises caution in dogs with epilepsy.^16,17

Collars and spot-ons that repel

Products containing permethrin, flumethrin or deltamethrin also stop ticks from biting, so they work before the bite. ESCCAP notes this matters most for the fastest diseases, such as TBE and ehrlichiosis.¹
These products also attack the parasite's nervous system. Permethrin is poisonous to cats. A dog product put on a cat, or close contact with a freshly treated dog, can cause tremors and seizures in the cat.^1,20

"Natural" alternatives

Amber, ultrasonic and similar collars did not repel parasites in a 2026 field trial.²¹
Essential-oil flea products are not risk-free. In a US poison-centre review, 89% of dogs exposed to them had side effects.²²
Garlic can destroy a dog's red blood cells. Do not feed it.²³

The manufacturers paid for most trials of the chemical products. That is normal for getting a product approved, but it means the studies are not independent.

Fleas

Most fleas are not on the dog. Only adult fleas live on the animal. The eggs, larvae and pupae make up most of the population and live in the home: in carpets, bedding and the car.¹ A related expert body says nearly 95% of a flea's life cycle happens there.²⁴
A female flea lays about 20 eggs a day. In a heated home fleas breed all year, and pupae can wait 6 months or more before they hatch.¹

How to check

Comb your dog with a fine flea comb. This is the most reliable way to find fleas.¹
Tap the combings onto damp white kitchen paper. Black specks that spread a red ring are flea droppings (digested blood).¹

If you find fleas

Vacuum every day, and wash the dog's bedding.¹ Treat the home as well as the dog, because that is where most of the fleas are.
Fleas carry a tapeworm (Dipylidium). Segments that look like grains of rice around the bottom mean the dog has, or recently had, fleas.¹
Some dogs become allergic to flea bites. Signs are intense itching and hair loss over the lower back and the base of the tail.¹

For a low-risk dog, ESCCAP itself advises regular combing and checking, and treatment only when fleas are found.¹

Worms after puppyhood

Our advice: test first, then treat

Your puppy was wormed on the standard puppy schedule. Puppies need this because roundworms pass from the mother to the puppies before birth and through her milk, and can make puppies ill before a test would find them.²⁵

Once your dog is an adult, we advise having a stool sample tested by a laboratory and worming only if worms are found, rather than worming on a fixed schedule.

What the experts say about testing

ESCCAP accepts regular stool testing instead of routine worming, if the tests are done as often as the worming would have been.²⁵ For an adult dog whose risk is unclear, that means at least 4 times a year. If children under about 6, or elderly or immunocompromised people, live in the house, it means every month.²⁵
ESCCAP also notes that worming more often makes it more likely that worms become resistant to the drugs, especially in kennels.²⁵ Drug-resistant hookworms are a growing problem in the USA.²⁶

Getting a reliable result

Collect fresh stool on 3 days in a row, about a teaspoon each time.²⁵
Ask the lab to also test for lungworm. This needs a separate test called the Baermann method, and the samples must not be mixed. Lungworm was found in 4.7% of dogs tested in southern Belgium, and it also occurs in Germany.^25,27 It has not been reported in Luxembourg.²⁸

Where the experts differ A negative test does not prove a dog is free of worms. Worms can be present before they lay eggs, and they do not shed eggs all the time.²⁵ Tests are also poor at finding tapeworms. ESCCAP therefore advises treating against tapeworms at least 4 times a year for dogs at risk, and every month for dogs that hunt or eat mice.²⁵ This matters in Luxembourg: about 1 in 4 foxes here carries the fox tapeworm, which can cause a serious liver disease in people.²⁹

Heartworm

Heartworm has not been found in Luxembourg. No case appears in the published research, and 50 foxes and 81 raccoons tested here were all negative.²⁸ The cases found in Germany were in dogs that had travelled.²⁸
It is common in southern Europe, and in Slovenia, Romania and Bulgaria. It is spreading in central and eastern Europe.^2,30
If you travel there between April and November, ESCCAP advises giving a heartworm preventive within 30 days of arriving. For stays of up to a month, one dose soon after you get home is enough.² Ask your vet before you go.
A related skin worm (Dirofilaria repens) has been found in dogs in Germany that had never left the country.²

Sandflies when you travel south

Here, protection is worth it. Sandflies are tiny flies that pass on leishmaniosis. In dogs this disease is usually lifelong, often comes back after treatment and can be fatal. People can catch it too.² (A "sand flea" is a different insect that lives in the tropics.³¹)

Where: around the Mediterranean (Spain, Portugal, southern France, Italy, Greece and nearby countries). In some areas up to 60% of exposed dogs are infected.²
When: from April to November. They bite mostly from dusk and through the night.^2,32
What helps:
- A repellent collar or spot-on, started before the trip. Depending on the product, trials found 50% to 100% fewer infections in protected dogs.³³
- Keeping your dog indoors from dusk to dawn, with fine mesh nets on windows and doors.²
- A vaccine is available for dogs over 6 months old. It lowers the risk but does not stop infection.^2,34

Most repellent products contain permethrin. Keep a freshly treated dog away from cats.

Sandflies were recorded in Luxembourg for the first time in 2023. No case of leishmaniosis caught in Luxembourg has been reported.³⁵