Healthy foxes will shine, even in moult. If you believe your fox is unwell, please seek veterinary advice.
Helminth Infections of UK Foxes (Cont.)
Helminth infections are diseases in which a part of the body is infected with parasitic worms (helminths). There are numerous species of these worm parasites, which are broadly classified into; tapeworms, heartworms, lungworms, roundworms, hookworms, whipworms and flukes - most of which are zoonotic (infecting both humans and animals).
Food Hygiene isn’t just important for us and our pets, it is just as vital for wildlife we are feeding also. Do not under-estimate how planting and good hygiene can go a long way to support wildlife, your pets and yourself.
Recommended veterinary anti-parasitic treatments include:
A continued list of parasites found in UK foxes can be seen listed below:
Hookworm
Uncinaria stenocephala (Northern Hookworm)
Ancylostoma tubaeforme (Canine Hookworm)
Ancylostoma caninum (Canine Hookworm)
Introduction and Background
Hookworms are blood-feeding intestinal parasites that can live in the small intestinal tract of humans and animals. Foxes become infected if they eat or tread on contaminated soil and the larvae burrow into the skin.
These parasites can cause severe anemia and inflammation in the small intestine tract, which can lead to severe and life-threatening illness, especially in the young.
Clinical Signs
Although hookworm is quite rare in the UK, it can be transmitted from mother to offspring and is prevalent on the continent.
Anemia and pale gums
Weakness and lethargy
Unexplained weight loss
Bloody diarrhoea
Itchy paws
Poor growth (in young developing animals)
Loss of interest in food
Behavioural changes
Diagnosis
Your vet will need a faecal sample in order to diagnose hookworm. The characteristic thin-shelled, oval eggs are easily seen on flotation of fresh feces from infected animals. Acute anemia and death from infections acquired via milk may be seen in young animals, before eggs are passed in their feces, as early as 1–2 weeks of age.
Treatment
Veterinary anti-parasite medications are used to treat animals with hookworm infections.
In dogs, fenbendazole, moxidectin, and pyrantel are approved for treatment of A caninum and U stenocephala infections. Milbemycin is also approved for treatment of A caninum infections in the US and UK.
When anemia is severe, chemotherapy may have to be supported by blood transfusion or supplemental iron, followed by a high-protein diet until the Hgb level is normal.
Heartworm prevention with products containing milbemycin control A caninum, whereas ivermectin/pyrantel, ivermectin/pyrantel/praziquantel, moxidectin, and moxidectin/imidacloprid control A caninum and U stenocephala and are approved for treating hookworm. The injectable formulation of moxidectin for heartworm prevention in dogs, also has significant efficacy against infection with A caninum and U stenocephala for at least 3 months.
Prevention
For captive animals, control of intestinal worms is based on preventative anti-parasite treatment, improved sanitation and increased awareness.
It is easy for any animal to get intestinal worms, but regularly treating captive animals with an effective worming product, as directed by the product, gives you peace of mind knowing they are being kept parasite free.
For wild foxes, control of intestinal parasites is difficult, but there is a lot people can do to help them.
Practice good hygiene:
Do not use bowls where it can be prevented (use a scatter feed approach; chopping up food finely and scattering it across the garden).
Do not feed more than 70g (or 200 calories) of fox-suitable food, per fox, every 2-3 days (calculated to ensure it won't affect natural behaviour and impact negatively on health).
Do not feed processed foods, it contributes to poor health and reduces the animals ability to resist disease.
If using bowls, use as many as you have wildlife visitors. Try to avoid having many animals share the same bowl. Just as for ourselves and our pets, food hygiene is important.
A natural bacteria called Bacillus thuringiensis, sold as a ‘soil drench', kills parasite and can be used to treat the soil.
Disinfect all utensils thoroughly every 24 hours. Ensure water bowls are included.
If using bowls or feeding stations, move them to different areas of the garden each night.
Keep grass and vegetation cut back and keep soil patches turned over regularly and powerhouse patios weekly.
Remove leaf litter and garden waste where parasites can hide.
Do not overfeed and allow slugs, snails, rats or mice to take advantage. They breed quickly and can carry many different parasites.
Do not allow mold and fungus to grow on food or in the environment.
Foxes will cache excess food and will defecate on any caches they do not wish to return to (which will also not occur if you are feeding daily). Ensure that faces and unwanted food caches are disposed of and reduce the amount you are feeding if excess and waste is an issue.
Canid-safe, parasite-busting, immune-boosting plants:
Mugwort, Garden Cress, Wild Strawberry, Dandelion, Broadleaf Plantain, Milk Thistle, Fennel, Turmeric, Chicory, Chervil, Carrot, Celeriac, Pumpkin, Barley, Rye, Hibiscus, Blackberry, Rosehip, Blueberry, Mulberry, Gooseberry, Juniper, Elderberry, Coriander, Parsley, Rosemary, Thyme, Sage, Peppermint, Sweet Basil, Lemon Balm, Sunflower, Valerian and Dill.
Parasite-repelling plants:
Astrenia, Anise, Wormwood, Rue, Rosemary, Chamomile, Fleabane, Fleawort, Sweet Bay, Mint, Lavender, Garlic, Pennyroyal, Pyrethrum, Sage, Citronella, Marigolds, Scented Geraniums, Beebalm and Catmint.
Whipworm
Trichuris vulpis (Fox Whipworm)
Introduction and Background
Whipworm is an intestinal parasite of the cecum and colon. It only affects canids such as foxes and dogs and is a relatively rare parasite in the UK. Eggs are transmitted through contaminated faeces when they are ingested and take around 8 weeks to cause an infection severe enough for symptoms to develop.
Because it takes a large amount of eggs to cause an infection, whipworm tends to only be found where large numbers of foxes cohabitate.
Clinical Signs
No signs are seen in mild infections, but as the worm burden increases and the inflammatory (and occasionally hemorrhagic) reaction in the cecum and colon becomes more pronounced.
Diarrhoea and dehydration
Fresh blood or mucous seen in the faeces
Anemia (hyponatremia in severe cases)
Lethargy
Unexplained weight loss
Changes in behaviour
Diagnosis
Whipworms are diagnosed by microscopy of faecal samples. Whipworm eggs are difficult to find and small numbers of eggs are passed on an inconsistent basis, therefore some samples may be falsely negative. Multiple stool samples are often required to diagnose whipworms.
Additionally, it takes approximately 12 weeks after hatching for a female adult to begin to lay eggs, so tests run soon after infection may also be falsely negative.
Treatment
The eggs are susceptible to desiccation (drying out), so maintaining good hygiene and eliminating moist areas, the risk of infection in foxes can be reduced considerably. However, T vulpis infections can be difficult to control.
For anthelmintic treatment of dogs, approved compounds include febantel, fenbendazole, milbemycin, moxidectin (topical), and oxantel in the US and UK.
Treatment should be repeated three times at monthly intervals because of the long prepatent period. Finally, milbemycin, milbemycin/lufenuron, milbemycin/spinosad, milbemycin/praziquantel, and moxidectin/imidacloprid, when administered for heartworm prevention, are also approved for control of T vulpis infections.
Prevention
For captive animals, control of intestinal worms is based on preventative anti-parasite treatment, improved sanitation and increased awareness.
It is easy for any animal to get intestinal worms, but regularly treating captive animals with an effective worming product, as directed by the product, gives you peace of mind knowing they are being kept parasite free.
For wild foxes, control of intestinal parasites is difficult, but there is a lot people can do to help them.
Practice good hygiene:
Do not use bowls where it can be prevented (use a scatter feed approach; chopping up food finely and scattering it across the garden).
Do not feed more than 70g (or 200 calories) of fox-suitable food, per fox, every 2-3 days (calculated to ensure it won't affect natural behaviour and impact negatively on health).
Do not feed processed foods, it contributes to poor health and reduces the animals ability to resist disease.
If using bowls, use as many as you have wildlife visitors. Try to avoid having many animals share the same bowl. Just as for ourselves and our pets, food hygiene is important.
Disinfect all utensils thoroughly every 24 hours. Ensure water bowls are included.
If using bowls or feeding stations, move them to different areas of the garden each night.
Keep grass and vegetation cut back and keep soil patches turned over regularly and powerhouse patios weekly.
Remove leaf litter and garden waste where parasites can hide.
Do not overfeed and allow slugs, snails, rats or mice to take advantage. They breed quickly and can carry many different parasites.
Do not allow mold and fungus to grow on food or in the environment.
Foxes will cache excess food and will defecate on any caches they do not wish to return to (which will also not occur if you are feeding daily). Ensure that faces and unwanted food caches are disposed of and reduce the amount you are feeding if excess and waste is an issue.
Canid-safe, parasite-busting, immune-boosting plants:
Mugwort, Garden Cress, Wild Strawberry, Dandelion, Broadleaf Plantain, Milk Thistle, Fennel, Turmeric, Chicory, Chervil, Carrot, Celeriac, Pumpkin, Barley, Rye, Hibiscus, Blackberry, Rosehip, Blueberry, Mulberry, Gooseberry, Juniper, Elderberry, Coriander, Parsley, Rosemary, Thyme, Sage, Peppermint, Sweet Basil, Lemon Balm, Sunflower, Valerian and Dill.
Parasite-repelling plants:
Astrenia, Anise, Wormwood, Rue, Rosemary, Chamomile, Fleabane, Fleawort, Sweet Bay, Mint, Lavender, Garlic, Pennyroyal, Pyrethrum, Sage, Citronella, Marigolds, Scented Geraniums, Beebalm and Catmint.
Flukes
Alaria alata (Fox Fluke)
Fasciola hepatica (Liver Fluke)
Introduction and Background
Foxes can get infected with flukes after swallowing the parasite, most often by eating contaminated raw vegetables or drinking contaminated water
Clinical Signs
In most cases, liver fluke infections are asymptomatic. When clinical signs occur they include;
Weakness and lethargy
Diarrhoea and dehydration
Chronic, deep, intermittent cough
Changes in behaviour
Migration of immature flukes can cause acute hepatitis and pancreatitis.
Diagnosis
A lung fluke infection is diagnosed by detecting eggs in a sample of faeces or mucous coughed up from the lungs of an infected fox. A sample of material from the trachea and bronchi can also be analyzed through procedures called 'tracheal wash' or 'bronchoalveolar lavage'.
Treatment
In dogs, off-label use of praziquantel 40 mg/kg given as a single oral dose is reported effective at killing adult liver flukes.
Prevention
Owners should be advised not to feed the foxes raw or undercooked freshwater fish.
For captive foxes, the correct anti parasite medication is required and a strict anti-parasite schedule must be followed. Whether the preventive you choose is given as a pill, a spot-on topical medication or as an injection, all approved heartworm medications work by eliminating the immature (larval) stages of the heartworm parasite. This includes the infective heartworm larvae, as well as the following larval stage that develops inside the animal.
Preventative programs for heartworm infection using milbemycin, milbemycin/lufenuron, milbemycin/praziquantel, milbemycin/spinosad, moxidectin/imidacloprid, ivermectin/pyrantel, or ivermectin/pyrantel/praziquantel.
Unfortunately, within 51 days, immature heartworm larvae can molt into an adult stage, which cannot be effectively eliminated by preventives. Because heartworms must be eliminated before they reach this adult stage, it is extremely important that heartworm preventives be administered strictly on schedule (monthly for oral and topical products and every 6 months for the injectable). Administering prevention late can allow immature larvae to molt into the adult stage, which is poorly prevented.
For wild foxes, control of fluke within the environment can be difficult, but there is a lot people can do to help themselves and wildlife.
Practice good hygiene:
Dump all standing water on your property (in flowerpots, containers, buckets etc.)
Clean water bowls daily, do not allow biofilm and mold to build.
If you have a water feature, add a waterfall or fountain to keep the water moving or treat it with a natural bacteria called Bacillus thuringiensis, which kills parasites.
Remove all damp leaf litter from the garden.
Keep gutters clean and flowing.
Keep grass and vegetation cut back.
Do not use bowls where it can be prevented (use a scatter feed approach; chopping up food finely and scattering it across the garden).
Do not feed more than 70g (or 200 calories) of fox-suitable food, per fox, every 2-3 days (calculated to ensure it won't affect natural behaviour and impact negatively on health).
Do not feed processed foods, it contributes to poor health and reduces the animals ability to resist disease.
If using bowls or feeding stations, move them to different areas of the garden each night. Use as many bowls as you have wildlife visitors, try to avoid having many animals share the same bowl.
Canid-safe, parasite-busting, immune-boosting plants:
Mugwort, Garden Cress, Wild Strawberry, Dandelion, Broadleaf Plantain, Milk Thistle, Fennel, Turmeric, Chicory, Chervil, Carrot, Celeriac, Pumpkin, Barley, Rye, Hibiscus, Blackberry, Rosehip, Blueberry, Mulberry, Gooseberry, Juniper, Elderberry, Coriander, Parsley, Rosemary, Thyme, Sage, Peppermint, Sweet Basil, Lemon Balm, Sunflower, Valerian and Dill.
Parasite-repelling plants:
Astrenia, Anise, Wormwood, Rue, Rosemary, Chamomile, Fleabane, Fleawort, Sweet Bay, Mint, Lavender, Garlic, Pennyroyal, Pyrethrum, Sage, Citronella, Marigolds, Scented Geraniums, Beebalm and Catmint.
Sources
https://www.wormwise.co.uk/wormopedia/hookworm
https://www.wormwise.co.uk/wormopedia/whipworm
https://www.troccap.com/canine-guidelines/other-systems/liver-fluke/
https://www.msdvetmanual.com/dog-owners/lung-and-airway-disorders-of-dogs/lung-flukes-in-dogs
This is something that UK fox groups on Face Book should have covered years ago. It's alright sharing fluffy fox photos then screaming "Call the Fox Man!" whenever a foox looks ill or has a "bad leg" but if you have an interest in foxes you need to be aware of these things -shutting down conversations on things like mange is not a good thing. Good to hear there are more posts to come and then everything should be covered.