Roundworms in Humans: How to Spot, Prevent, and Protect Your Family 🧼🧠

By Dr Duncan Houston

⚡ Quick Answer

Roundworms from dogs and cats can infect humans, especially children, through contaminated soil or poor hygiene.

In most cases symptoms are mild, but in rare situations the larvae can affect organs or the eyes and cause serious damage.

The good news is that simple steps like hand washing, regular deworming, and cleaning up pet waste are highly effective at preventing infection.

🧠 Why This Matters

Roundworms are extremely common in pets.

What many people do not realise is that they can also infect humans.

Most cases occur in children, and while many infections are mild or unnoticed, some can lead to significant health issues.

The key point is that this is preventable.

🦠 What Are Roundworms?

Roundworms are intestinal parasites found in dogs and cats.

The two main types that affect humans are:

• Toxocara canis from dogs

• Toxocara cati from cats

Pets pass roundworm eggs in their faeces.

These eggs then develop in the environment over a few weeks before becoming infectious.

This means the highest risk comes from contaminated soil, not fresh waste.

📊 How Common Is Human Exposure?

Exposure is more common than most people think.

• a significant proportion of soil in public areas can contain roundworm eggs

• many people have been exposed at some point in their life

• children are at the highest risk

Young children are more likely to:

• play in soil or sand

• put their hands in their mouth

• have less developed hygiene habits

🔍 What Happens If Humans Are Infected?

Humans are not the natural host for roundworms.

So when eggs are ingested, the larvae hatch and migrate through the body instead of staying in the intestines.

This causes inflammation as the immune system reacts.

🧬 Types of Human Infection

Covert Infection

• mild symptoms

• fatigue

• abdominal discomfort

• headache

Often goes unnoticed and resolves on its own.

Visceral Larva Migrans

• larvae travel through organs such as liver or lungs

• can cause inflammation and more severe illness

• more common in young children

Ocular Larva Migrans

• larvae migrate to the eye

• can cause vision problems or blindness

• often affects children

This is the most serious form and highlights why prevention matters.

💡 How Infection Happens

People are usually infected by accidentally ingesting roundworm eggs.

Common sources include:

• contaminated soil

• sandboxes

• unwashed hands

• dirty objects placed in the mouth

Contact with pet fur is possible but considered a lower risk.

🚫 You Cannot See the Risk

Roundworm eggs are microscopic.

Contaminated soil can look completely normal.

They can survive in the environment for long periods, making outdoor areas a potential risk.

🧼 How to Prevent Infection

Prevention is simple and very effective.

🧴 Wash Hands

• before eating

• after outdoor play

• after handling pets

🐾 Deworm Pets Regularly

• follow veterinary recommendations

• especially important for puppies and kittens

• use routine parasite prevention

🪣 Cover Sandboxes

• prevents contamination from animals

• reduces exposure risk for children

🧹 Clean Up Pet Waste

• remove faeces daily from your yard

• dispose of waste properly in public areas

🍽️ Food Safety

• cook meat thoroughly

• wash produce when needed

👶 Supervise Children

• discourage eating dirt

• keep toys clean

• encourage hand washing

🚩 When to Be Concerned

Seek medical advice if there are:

• unexplained vision issues

• persistent cough or fever

• abdominal discomfort

• unusual fatigue

These are uncommon but important to recognise.

🐾 Final Thoughts

Roundworms are a common parasite, but human infection is largely preventable.

Simple habits like:

• washing hands

• deworming pets

• cleaning up waste

can dramatically reduce risk.

Most households can manage this easily with a little awareness and consistency.

❓ FAQ

Can I get roundworms directly from my pet?

Not directly. Infection usually comes from contaminated soil, not fresh contact.

Are children more at risk?

Yes. Their behaviour and developing hygiene habits increase exposure.

How often should pets be dewormed?

This depends on age and lifestyle, but regular parasite prevention is essential.

Is this common?

Exposure is relatively common, but serious disease is rare.

Can it be prevented completely?

Risk can be reduced significantly with good hygiene and pet care.

If you want help staying on top of parasite prevention, pet health tracking, and reminders, ASK A VET™ can help you manage everything in one place and keep your household safer.