The first cases of Lyme disease (LD) occurred in the US, but it's now acknowledged to be a worldwide problem. Britain had its first official death due to LD in December 2005: "liver disease due to Lyme sepsis", according to the autopsy. In May of this year, a 38-year-old British professor committed suicide after developing dementia brought about by LD. It's particularly prevalent at this time of the year-late spring and early summer.

The number of diagnosed cases of Lyme disease are now rising - and not just because doctors are finally beginning to recognize it, but also possibly as a result of global warming. And, as with many new-disease discoveries, a whole raft of previously mysterious conditions are now being laid at the door of LD, including chronic fatigue (CFS/ME), multiple sclerosis (MS) and even autism. Could we be witnessing the start of a new epidemic? "Many of the diseases that are considered incurable by conventional medicine may have some kind of Lyme component," says American alternative practitioner Dr Lee Cowden.

What is Lyme disease? In essence, it's a kind of malaria, although it emerges not from the swampy jungle, but from temperate forests. Like malaria, the disease is transmitted by being bitten by a blood-feeding creature-in the case of LD, not by an insect, but a tick, an arachnid, that lives on animals such as cattle, birds and even mice, but primarily deer.

Where it all began
Lyme disease first appeared more than 30 years ago as a mysterious disease outbreak in an American town called Lyme, in Connecticut. In the spring of 1975, there was a cluster of cases of what appeared to be juvenile arthritis. Children as young as 10 began to develop severe joint pain. Doctors from nearby Yale University were called in to investigate, and were puzzled by the appearance of odd rashes on the children's skin. Months of detective work finally led the doctors to connect the symptoms to a disease that had first been described in Europe almost a century before as 'sheep-tick fever'.

After years of further detective work, researchers traced the illness to a rogue spirochaetes bacterium in the patients' blood known as Borrelia burgdorferi-hence, the alternative name of 'Lyme borreliosis'. But where had it come from? Already alerted to the fact that it might be due to a tick bite, the scientists began a hunt among the local animal population. The Borrelia microorganism was finally tracked down to a tick of the genus Ixodes that lives on deer. This tiny arachnid-related to mites, spiders and scorpions, having eight legs-has a correspondingly tiny mouth, so its bite is rarely felt, which may be one reason why it was able to elude detection for so long. Ixodes is also cleverly able to inject its prey with a local anaesthetic, further disguising its attack. In fact, most victims of Lyme disease have no idea they were ever on the tick's hit list.

In fact, it's likely that Ixodes has to remain undetected because it's believed to be an inefficient feeder. It needs to be plugged in to its prey for hours to obtain sufficient nourish-ment. One indication of this is the probability that B. burgdorferi is not transmitted until the tick has been attached for at least 12 hours.