Blood-sucking worm disease warning: Parasite spread by animals first spotted in homes in Britain

A British dog has been infected with blood-sucking worms that can grow up to 15cm in size and can make the jump to humans – where they can cause blindness.

The case, detailed in a government report, is a first in Britain and appears to be linked to the animal’s owner feeding it a trendy raw food diet.

The uncooked nature of the meat in raw food diets puts supplies at risk of becoming contaminated with parasites or pathogens.

Although previous cases of the parasite, called Linguatula serrata, have been recorded in Britain, all involved canines imported to Britain from countries where the infection is more common.

In contrast, the most recent case occurred in a dog that had never left Britain.

People can become infected with the worms by coming into contact with the saliva, mucus or feces of an infected pet.

From there, the parasites can cling to the back of the throat or possibly enter the intestines and burrow into other tissues, causing a host of potential problems such as breathing difficulties, aching pain and vision loss.

In rare cases, the worms have even been found in people’s eyes.

A British dog has been struck by an infection from disgusting blood-sucking ‘tongue worms’ that can make the jump to humans. Pictured the Linguatula serrata parasite

Experts were unable to determine exactly how the dog became infected, nor did they indicate exactly where in the country this case occurred.

Infection in dogs can occur when they consume the feces of an infected animal, which is rich in eggs hatched by the worms.

It can also happen if a dog eats the meat of an infected animal.

People can become infected with the worms by eating undercooked meat, but also through food accidentally contaminated with infected feces and through the saliva and snot of pets.

In humans, young worms can cling to the surface of the throat or crawl up from the stomach, this is called linguatulosis.

Symptoms of this include excessive mucus, irritation, throat bleeding, frequent sneezing and breathing difficulties.

Human infection can also cause a condition called visceral pentastomiasis, in which ingested worm eggs hatch in the intestines and lodge in other tissues, such as the body’s lymph nodes, liver, lungs and eyes.

The symptoms of this condition vary depending on where the worm larvae – called ‘nymphs’ – end up.

The case, detailed in a government report, is a first in Britain and appears to be linked to the pooch’s owner feeding him a trendy raw food diet, with Britons previously warned that such diets pose a risk could pose to public health. Stock image

They include abdominal pain, chronic cough and night sweats, as well as eye pain and vision loss if the nymphs happen to hatch in someone’s eye.

However, with many infections, no symptoms develop at all and the presence of the worms is only revealed during an unrelated medical test or even an autopsy.

Clinicians typically treat patients with visceral pentastomiasis only if the parasites cause symptoms, because otherwise the nymphs die about two years after they hatch.

Although cases have been reported in all ages, children are generally considered more vulnerable to infections due to a more careless attitude towards hygiene around pets.

Infection in pets is usually avoided by ensuring that the meat fed to them is frozen or properly cooked.

In the new case, recorded in March last year, British officials said the risk of human infections was reduced by treating the dog and advising the owner to stop feeding it raw food.

Despite being called tongue worms, Linguatula serrata does not actually infect the tongue but attaches to tissue further down the throat.

The common name instead refers to how the creature’s physical form resembles a ‘tongue’.

Technically, they aren’t ‘worms’ either. The creatures are actually a bizarre relative of insects, spiders and crustaceans.