Raw pet food has been linked to an outbreak of feline tuberculosis that has infected dozens of cats and two people in the United Kingdom.

One hundred people and 90 felines have been referred for tests, researchers have told U.K. media.

The issue was identified when six cats were taken to separate vets across England with clinical signs of Tuberculosis (TB) and five of them died. Tests confirmed the animals were infected with Mycobacterium bovis that usually causes TB in cattle. It can also infect rodents, deer and people.

An additional seven cats living in the same households were infected but did not have symptoms. All affected animals were indoor pets and had no contact with wildlife that could have passed on disease.

Two owners of affected cats were found to be interferon-gamma release assay (IGRA) and Mantoux (tuberculin skin test) positive and one required anti-tuberculosis medical therapy.

Pet food the common factor

Vets at the University of Edinburgh’s Royal (Dick) School of Veterinary Studies found the only common factor was cats had all eaten the Wild Venison variety of a brand of pet food called Natural Instinct. A report on the initial cases was published in the Journal of Feline Medicine and Surgery.

The team did not test food samples so cannot confirm it was the source of infections. Other possible sources of exposure were excluded including wildlife contact, access to raw milk, presence of rodents in buildings in which the cats lived and exposure to known infectious humans.

Symptoms of TB in cats include swollen belly, persistent cough and enlarged lymph nodes.

Natural Instinct recalled its Wild Venison natural cat food in 250-gram and 500-gram packs in December 2018 because a supplier of the wild venison offal had not inspected it in accordance with European requirements. Absence of inspection means safety of the product could not be confirmed.

As there was no inspection post mortem it was not classed as category 3 material. This category is for animal by-products from carcasses passed fit but not intended for human consumption.

All pack sizes and dates from March until August 2019 were affected. Distribution included the U.K., Ireland and Guernsey. The line of cat food was launched in 2012 and venison was sourced in Britain.

Product recalled and discontinued

A spokesperson from Natural Instinct said it no longer makes or sells the venison cat food. The last manufacturing run was on Nov. 16, 2018.

“We can assure our customers that Natural Instinct followed, and continues to follow, every food standard, hygiene regulation and best practice required to produce raw pet food in the commercial market place,” said the spokesperson.

“As a responsible manufacturer, we are regularly inspected by the Animal and Plant Health Authority (APHA). We have complied with all of the necessary requirements, and consequently APHA have confirmed they are satisfied all standards have been met by us.”

The spokesperson added the firm was working with the Food Standards Agency and other organizations as part of the investigation into the venison cat food product and to ensure high standards across the industry.

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