11/09/2012 18:48 BST | Updated 11/11/2012 05:12 GMT

Watch Out Dog Owners - It's a Jungle Out There

It's been a hectic couple of weeks getting together the It's a Jungle Out There campaign up and running. Working alongside the legendary David Bellamy has been great, with opportunities to hear some amazing tales from his extraordinary career.

My particular favourite anecdote was how he was driving along listening to the radio when they started a David Bellamy impersonation competition live on air. Typical of his sense of humour he decided to call in and have a go. He came second! I can't imagine what it must have been like at the time having so many people take you off, and even caught myself a few times during the filming slipping into an impression of him when talking about nasty, little parasites. It's a subject that's incredibly well suited to his delivery with lots of gruesome tales about burrowing mites and invasive worms.

It's not a comfortable topic as I know from working in practice. Almost every day I see people start scratching just at the mention of fleas and ticks, but it's important information they need to know about. And it's also a fascinating piece of natural history because these parasites have millions of years of evolution behind them that has resulted in some amazing survival strategies.

Angiostrongylus vasorum is a great example. This recent addition to the British Isles has moved over from the European mainland and is making its way across the country not under its own steam. It is carried by foxes and excreted in their faeces. One study in 2008 showed that 23% of foxes in the South-west were carrying this parasite and you know how many gardens a fox can visit. But the larvae deposited in the soil by the fox have still got to find their way into a dog and so they have evolved a cunning transport plan. Slugs and snails grazing in the undergrowth become infected by the larvae and it's now mobile once more to be dispersed all over the garden. Dogs are not known to be fussy eaters and the unwary slug that slides into a water bowl or happens to be on the wrong bit of grass can be accidentally ingested and the dog is infected. This unfortunately is the not the end of its journey because this worm is known as Lungworm because this is where it's commonly found. They migrate through the gut wall into the blood stream and set up home in the major blood vessels around the heart. Here they mate and release their offspring into the lungs to be coughed up and swallowed to start the whole process again. Dogs have little defence against this nasty invader and if they get large numbers building up it can cause fatal bleeding episodes with very little warning. I can tell you the potential signs; coughing, lethargy, pale gums, etc but they are vague and subtle and often missed. Prevention is key, rather than worry and wait, speak to vet and regularly treat.

It's not just slugs and snails that parasites hijack for their cause it can be use humans too. Many of us, I'm afraid to say are carrying little hibernating worms called toxocara. These are the most common roundworms or cats and dogs and have been living alongside and within us for thousands of years. Their true home is the intestines of our pets but similar to lungworm have evolved specialised behaviours to increase the chance of them passing onto the next generation of pets. In dogs these worms can migrate from mum to puppy whilst the puppies are still in the womb and in both dogs and cats they will also move into the milk to guarantee the litter are all infested from the start. Finally eggs are also passed out regularly in the faeces to seed the environment as well.

This is where we come in. Handling contaminated soil outside in the garden or park, or even just stroking the dog we can pick up these eggs, as in one veterinary study a quarter of dogs were found to have eggs stuck to their coats. If we accidentally ingest these eggs they cannot mature and reproduce as they do in dogs but they do something just as bad. They burrow out of the gut and into our tissues to wait. Wait for what? Well this behaviour evolved a long time ago when lots of other animals who may have ingested the wrong worm were scavenged on by wolves or other wild carnivores. The encysted larvae have again found a proper home.

Thankfully, the vast majority of people will never know if they are carrying these little critters arrested within their bodies but in some very rare cases they do make their presence known as they migrate to the eyes and can cause blindness. Who of you knew that your own bodies were host to such a myriad of tiny beasts?

It's a true miniature safari and who better to be on safari with than David Bellamy. Now wash your hands.

Join us on safari here: