Processionary caterpillars and viper bites: Mediterranean dangers for dogs

Two hazards that many northern-European guides barely mention are a regular part of life for dog owners in Greece and around the Mediterranean: pine processionary caterpillars and vipers.

Pine processionary caterpillars

What they are

The caterpillars of the pine processionary moth (Thaumetopoea pityocampa) live in pine trees. In winter you'll see their white, silky nests like candyfloss in the branches. In late winter and spring — roughly January to April in Greece, depending on altitude and weather — they come down and march across the ground nose-to-tail in long lines.

Their thousands of tiny hairs carry an irritant protein. Curious dogs sniff, lick or pick them up, and the hairs embed in the tongue and mouth.

Signs

• Sudden heavy drooling and pawing at the mouth
• Swollen, painful tongue, which may turn dark
• Difficulty swallowing, vomiting
• Swelling of the face; occasionally breathing difficulty

Without fast treatment, part of the tongue can die and slough away.

What to do — fast

1. Don't touch the caterpillars or the hairs with bare hands. Wear gloves; they hurt people too.
2. Gently rinse the mouth with plenty of water — a bottle or hose on a gentle flow, letting it run out. Don't rub the tongue; rubbing breaks the hairs and releases more toxin.
3. Go to a vet immediately, ideally within two hours.

Timing really matters. In a study of more than 100 affected dogs, those whose mouths were flushed more than six hours after contact were around nine times more likely to already have tongue necrosis when they reached the vet (45% versus 5%). With prompt treatment, nearly all survived.

Prevention

In caterpillar season, keep dogs on a lead under and around pine trees, and avoid parks where nests are visible. Report nests in public areas to your municipality.

Viper bites

The risk

Vipers are Europe's only native venomous snakes, and Greece is home to several species, including the nose-horned viper. Dogs are usually bitten on the face, neck or front legs while investigating. Bites are most common in warm months, in rocky ground, scrub and dry-stone walls.

Signs

• Rapid, painful swelling, often of the face or leg
• Two small puncture wounds (not always visible)
• Bleeding or bruising around the bite
• Lethargy, trembling, fever, vomiting
• Later: pale gums, blood in the urine or black stools

Swelling around the face or throat can become severe enough to block the airway.

What to do

• Keep your dog calm and as still as possible — carry it if you can. Movement spreads venom.
• Phone ahead and go straight to the vet. Antivenom and supportive care work best early.
• Don't cut the wound, try to suck out venom, apply a tourniquet or bandage, or put ice on it.
• Don't try to catch or kill the snake. If it's safe, take a photo from a distance.

The bottom line

With both caterpillars and vipers, time is the single biggest factor in how well a dog recovers. Know where your nearest emergency vet is before you head out — PET-ABC shows the closest clinics to your location.