Largest Study With Vet Practices Reveals the Infectious Diseases Fleas Carry And The Risks Posed To Human Health

  • Findings from The Big Flea Project revealed 1 in 4 cats and 1 in 7 dogs sampled in the study were found to be carrying fleas
  • 79 percent of Brits admitted they did not know fleas could lead to diseases such as bartonellosis, an infectious disease that can be transmitted to people
  • More than half of the nation (57 percent) do not understand the lifecycle of a flea or the meaning of repeated in-home flea infestations
  • TV Presenter Michaela Strachan speaks out about the importance of protecting both pets and humans against fleas

Milton Keynes, May 10 2019 – To raise awareness of the diseases that fleas carry, MSD Animal Health – in partnership with the University of Bristol – conducted the UK’s largest ever study of vet practices, called The Big Flea Project.

The findings from the study revealed that out of the 1,475 pets that were examined, 1 in 4 cats and 1 in 7 dogs were found to be carrying fleas. Of the flea samples studied, 11 percent carried Bartonella, an infectious bacterium that can cause disease. Most commonly found were the Bartonella species that can cause cat scratch disease.

Cat scratch disease in humans usually results in headaches, fatigue and fever, this often doesn’t require treatment. However, in severe cases antibiotic treatment is required and children may be more at risk than adults.

The study also showed that southern parts of the UK had higher levels of flea infestation than northern regions.

A previous survey* carried out by MSD Animal Health revealed more than three quarters of Brits (79 percent) admitted they did not know fleas carried bacteria and other infectious pathogens, with a third of those surveyed admitting they had been bitten by fleas. Five percent said they had been left permanently scarred by bites from fleas.

The national survey of UK pet owners has shown 11 percent of UK pet owners had suffered up to three flea outbreaks. As it takes at least 12 weeks to break the flea life cycle, continuous protection is needed to successfully rid the pet of fleas. However, a reported 57 percent of pet owners in Britain are unsure of the lifecycle of a flea, which is often the reason for multiple outbreaks occurring.

Other pathogens were also found to be carried by fleas included the dog tapeworm, which is unsightly and unpleasant.

Backed by wildlife TV presenter, Michaela Strachan, the national campaign aims to educate pet owners about the dangers of fleas and the risk they pose to both human and pet health. Michaela commented: “This is the largest ever study of vet practices in the UK and it really shows up a lack of understanding that most people have around fleas, their life cycle and how to properly treat their pets to protect them from fleas and the possible diseases they can carry.

“I think it’s a real wake up call and shows the best way to prevent problems and infestations is proper and regular preventative treatments.”

Working with vets across the UK, The Big Flea Project checked more than 1,470 cats and dogs for the parasites, where a total of 323 were found to be carrying fleas. These findings were supported by a previous survey of British pet owners where 82 percent admitted that they struggle to keep their pets’ fleas under control, and 57 percent admitted they knew nothing about the life cycle of a flea before their pet caught them.

Richard Wall from the University of Bristol said: “While we were already aware of the impact that fleas have on pets, the greater number of pets with flea infestations in the southern parts of the UK, and the higher number carrying pathogens than expected were surprising and interesting.

“In light of these findings, we hope that pet owners will become more aware of the problem that fleas pose not only to their pets, and we would urge anyone unsure of what adequate treatments there are available to speak to their vet.”

MSD Animal Health and The University of Bristol has published the results as part of The Big Flea Project, which aims to raise awareness of fleas and the threat they pose to both pets and humans’, while educating pet owners on how to treat fleas effectively.

Hannah Newbury, Vet from MSD Animal Health commented: “Fleas are often a major source of irritation for both pets and humans alike, which is why it was so important for The Big Flea Project to gain a better understanding of the extent and nature of the risk that fleas pose in the UK.”

“We are confident the findings revealed by the study will help pet owners understand the scale of the problem more clearly, and in turn will encourage them to seek professional advice. This will help them understand the lifecycle of the flea and the need to control them.”

The campaign highlights the need for pet owners to discuss the options for appropriate flea protection with their vet. Vets can prescribe flea treatments that best suit the needs of your pets, with treatments including sprays, collars, monthly and 12 weekly spot ons and chewable tablets for full flea protection.

The Big Flea Project follows the success of the Big Tick Project that launched in 2015 and examined over 6,000 tick samples in the UK, contributing to the largest-ever study of ticks on dogs and cats in Britain.

For more information visit the Big Flea Project website:

About MSD Animal Health
For more than a century, MSD, a leading global biopharmaceutical company, has been inventing for life, bringing forward medicines and vaccines for many of the world’s most challenging diseases. MSD Animal Health, known as Merck & Co Inc. Kenilworth NJ, in the United States and Canada, is the global animal health business unit of MSD. Through its commitment to the Science of Healthier Animals™, MSD Animal Health offers veterinary surgeons, farmers, pet owners and governments one of the widest range of veterinary pharmaceuticals, vaccines and health management solutions and services. MSD Animal Health is dedicated to preserving and improving the health, well-being and performance of animals. It invests extensively in dynamic and comprehensive R&D resources and a modern, global supply chain. MSD Animal Health is present in more than 50 countries, while its products are available in some 150 markets.

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*MSD Animal Health questioned 2,000 UK residents in March 2018.
*MSD Animal Health and the University of Bristol collected samples for The Big Flea Project between 1st April – 1st June 2018