---
title: "Heartworm vs Lungworm in Dogs UK"
description: "UK guide — lungworm (Angiostrongylus) is common in Britain; heartworm (Dirofilaria) is rare but a travel risk. Different spread, symptoms, and prevention."
url: "https://pethealth.org.uk/health/heartworm-vs-lungworm-dogs-uk"
canonical: "https://pethealth.org.uk/health/heartworm-vs-lungworm-dogs-uk"
date_published: "2026-06-25"
date_modified: "2026-06-25"
source: "PETHEALTH+"
---

# Heartworm vs Lungworm in Dogs UK

**Lungworm and heartworm are not the same parasite.** In the UK, **lungworm (Angiostrongylus vasorum)** is the main concern — spread by slugs and snails. **Heartworm (Dirofilaria immitis)** is rare in Britain but matters for dogs travelling to southern Europe. Prevention products differ — ask your vet.

## Quick comparison

| Feature | UK lungworm | Heartworm |
|---------|-------------|-----------|
| **Parasite** | *Angiostrongylus vasorum* | *Dirofilaria immitis* |
| **Spread** | Slugs, snails, slime trails | Mosquito bites |
| **UK prevalence** | Widespread and increasing | Rare (mainly travel/import cases) |
| **Main signs** | Cough, bleeding, neurological signs | Cough, exercise intolerance, heart failure |
| **Prevention** | Monthly vet wormers that cover lungworm | Travel-specific heartworm preventatives |

## UK lungworm — the priority for most owners

According to the PDSA and BVA, **lungworm has spread across much of England, Wales, and Scotland**. Dogs ingest larvae from:

- Eating slugs or snails
- Licking **slime trails** on grass, toys, and outdoor bowls

Warning signs include **coughing**, **bleeding** (nosebleeds, pale gums, bruising), weight loss, seizures, and collapse.

Full guide: [Lungworm in dogs UK](/health/lungworm-in-dogs-uk)

**Not all wormers cover lungworm** — check your [dog worming schedule](/health/dog-worming-schedule-uk) with your vet.

## Heartworm — UK context

Heartworm larvae are spread by **infected mosquitoes**. Worms mature in the heart and pulmonary arteries over months, causing progressive heart and lung disease.

### Is heartworm a UK problem?

**Native UK infection is uncommon.** The BVA notes heartworm as a **travel and import concern** — dogs visiting or relocated from **southern Europe, the Mediterranean, and other warm regions** may be at risk.

UK owners should discuss heartworm prevention with their vet **before travel abroad** — see [Travelling with pets UK](/health/travelling-with-pets-uk).

Full guide: [Heartworm in dogs](/health/heartworm-in-dogs)

## Overlapping symptoms

Both parasites can cause:

- Coughing — see [Why is my dog coughing?](/health/why-is-my-dog-coughing)
- Exercise intolerance — see [Why is my dog panting heavily?](/health/why-is-my-dog-panting-heavily)
- Weight loss — see [Unexplained weight loss in dogs](/health/dog-weight-loss-unexplained)

**Bleeding disorders** are more characteristic of **lungworm**. **Heart failure and fluid belly** are more typical of advanced **heartworm**.

Only **veterinary tests** can confirm which parasite — or another condition — is involved.

## Prevention summary for UK dogs

1. **Year-round lungworm prevention** — vet-prescribed product that explicitly covers *A. vasorum*
2. **Routine intestinal worming** — roundworm and tapeworm per [worming schedule](/health/dog-worming-schedule-uk)
3. **Travel heartworm prevention** — if visiting at-risk countries, start before travel per vet advice
4. **Never use dog wormers on cats** without veterinary direction

## When to see your vet urgently

Seek emergency care for:

- Collapse, severe breathing difficulty, or seizures
- Nosebleeds or unexplained bleeding
- Pale gums or sudden weakness

## Related guides

- [Lungworm in dogs UK](/health/lungworm-in-dogs-uk)
- [Heartworm in dogs](/health/heartworm-in-dogs)
- [Fleas and ticks in pets](/health/fleas-and-ticks-in-pets)
- [Lyme disease in dogs UK](/health/lyme-disease-dogs-uk)

## FAQs

### What is the difference between heartworm and lungworm in dogs?

They are different parasites. UK lungworm (Angiostrongylus vasorum) spreads via slugs and snails and is common in Britain. Heartworm (Dirofilaria immitis) spreads via mosquitoes and is rare in the UK but a risk after travel to southern Europe.

### Is heartworm common in the UK?

No — native UK heartworm infection is uncommon. Cases are usually linked to travel abroad or imported dogs. Lungworm is the parasite UK owners should prioritise for prevention.

### Do the same wormers prevent both?

Not necessarily — many standard wormers do not cover lungworm. Some travel products cover heartworm. Your vet will recommend products based on UK lungworm risk and any travel plans.

### Can a dog have both heartworm and lungworm?

Theoretically yes in a dog with UK lungworm exposure and travel-related heartworm risk — but this is uncommon. Veterinary blood tests help identify which parasite is involved.

## Sources

- [PDSA — Lungworm in dogs](https://www.pdsa.org.uk/pet-help-and-advice/pet-health-hub)
- [Blue Cross — Lungworm](https://www.bluecross.org.uk/pet-advice)
- [BVA — Parasite treatments](https://www.bva.co.uk)

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Last modified: 2026-06-25