Background: Virtually all horses are infected with helminth parasites.

Forty-four percent had at least one parasite detected, and 24% were infected with helminths.

Alterations in lung function and pulmonary symptoms have been described in patients infected with helminths with a lung cycle.

Many of our human ancestors would have been infected with helminths, as are large numbers living in developing nations today.

Over 25% of the world's population are infected with helminth parasites, the majority of which colonise the gastrointestinal tract.

Fleming says he advises the multiple sclerosis patients who email him at a rate of around one a week against self- infecting with helminths.