Alternative health centres are giving backpackers dangerous advice on malaria prevention by recommending unproven homoeopathic remedies instead of effective conventional drugs.

An investigation has revealed that every one of ten randomly selected homoeopathic clinics and pharmacies was willing to recommend its products as an alternative to proven prophylactic drugs, in defiance of advice from the Health Protection Agency.

The findings prompted leading tropical medicine experts to warn travellers that homoeopathic preparations offer no protection against malaria and other life-threatening diseases, and should never be taken instead of preventive treatments that do work.

Homoeopathy is controversial as there is no scientific evidence that it is effective. Remedies are created by diluting substances to an extreme degree, usually so not a single molecule of the main ingredient is left, and most scientists consider that its only medical value lies in the placebo effect. It is generally accepted that the remedies are not themselves dangerous, as they contain no chemically active ingredients, but they can put people at grave risk when used in place of medications that are needed to treat or prevent disease.

Ron Behrens, director of the Hospital for Tropical Diseases Travel Clinic in London, said that it is critical that people visiting malarial regions do not substitute homoeopathic preparations for prophylactic drugs.

“We are urging the public to take on board this warning at a time of year when many people are planning to travel,” he said. “The misleading travel advice being given by homoeopaths is not a trivial problem. We have treated people at the Hospital for Tropical Diseases who thought that they were protected by homoeopathic medicines and contracted malaria. The messages given by some homoeopaths are inaccurate, counter-productive and place lives at risk.”

Professor Brian Greenwood, of the London School of Hygiene and Tropical Medicine, said: “The use of homoeopathy creates a more dangerous situation than taking no precautions if the traveller assumes that she or he is protected and does not seek help quickly for any illness that might be malaria.”

In the investigation, Simon Singh, a science writer and broadcaster, picked ten clinics and pharmacies at random from the internet, and sent Alice Tuff, an intern with the charity Sense About Science, to approach them for advice.

Ms Tuff, 23, posed as a backpacker about to start a ten-week truck tour through central and southern Africa that would take her through several malarial zones. She told each homoeopath that the anti-malarial drugs prescribed by her doctor were making her feel unwell, and asked whether they could provide an alternative.

In every case, a homoeopathic remedy was recommended, and none of the practitioners advised Ms Tuff to keep taking her conventional drugs. None referred her back to her GP, who would have been able to prescribe an alternative drug that might have more tolerable side-effects.

Only three of the homoeopaths advised on mosquito bite prevention, and only one gave advice on the symptoms of malaria and recommended that she seek professional medical help if she experienced these. Four of the homoeopaths offered anecdotal stories of patients who had used their preparations to prevent malaria.

Dr Singh said: “Homoeopathy is not just useless, it is worse than useless in the case of malaria because it dupes people into thinking that they are protected when they are not. I was shocked that there was such willingness to give advice and sell products that would leave people exposed to a highly dangerous disease.”

Melanie Oxley, of the Society of Homoeopaths, said that she was concerned by the findings, as there was no evidence that homoeopathy could guard against malaria. It should be used together with conventional medicine, she said.

BITE THAT KILLS THREE MILLION A YEAR

There is no evidence that any homoeopathic preparation is effective against malaria

Three homoeopathic preparations were recommended for malaria prevention: malaria officinalis, made from tissue from a sick person or vegetation from malarial swamps; China sulph, made from quinine-producing trees; and natrum mur, based on salt

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