A leisurely stroll by the beach while on a Caribbean holiday left a young Canadian couple with swelling and painful blisters on their feet.

Ms Katie Stephens, 22, and Mr Eddie Zytner, 25, contracted parasitic hookworms - also known as larva migrans - on their feet, most likely from walking barefoot on the beach at their resort.

The couple from Ontario were on a week-long getaway to the Dominican Republic earlier this month and stayed at the IFA Villas Bavaro Resort in Punta Cana.

Last Tuesday (Jan 23), Ms Stephens took to Facebook to warn other holiday-goers to tread carefully on sandy beaches and to always wear shoes.

"If your feet become incredibly itchy please get it checked out right away, since we simply thought it was just bug bites and it became worse as each day passed," she wrote.

She also shared photos of their feet in the post, which were severely swollen and covered in red, pus-filled bumps at the toes.

In an interview with Canadian broadcast CTVNews last Friday, Ms Stephens said that they had been scratching their feet for most of the trip, but assumed that the itch was caused by sand flies.

A day after they returned home, on Jan 19, Mr Zytner noticed that his feet had started to swell.

He saw two doctors, but they were unable to tell what had caused the symptoms.

When Ms Stephens' feet became swollen as well, the couple went to a hospital, where a third doctor was able to diagnose their condition.

The doctor said he had seen a similar case from a tourist who recently returned from a trip to Thailand.

CTVNews reported that hookworms can enter the skin if it comes into contact with an infected surface.

The couple reportedly faced obstacles in getting treatment, as the drug they required - Ivermectin - was not licensed in Canada.

Ms Stephens told CTVNews that their request to the Canadian health authorities was denied.

Her mother drove to Detroit in the United States to pick the medication up instead.

While the pair are currently relying on crutches to get around, Mr Zytner said last Friday that their recovery has shown progress.

Referring to his feet, he said: "They looked a little bit better yesterday. We're getting our bandages changed again ... So we'll have another chance to look at them and see how it's progressing."