Many homeopaths and naturopaths continue to tout the disease-preventing abilities of nosodes, fuelling a heated debate with public-health advocates over the efficacy of these homeopathic remedies, which are often promoted as vaccine alternatives.
Science has been of little help in the debate: A number of studies have tried to evaluate the effectiveness of nosodes, but the vast majority contain major flaws that make the results difficult to trust.
Now, a prestigious group of researchers at McMaster University in Hamilton is conducting a high-quality scientific experiment to determine whether nosodes actually work.
The point is to use scientific evidence to find answers in an area often fraught with emotional tension, said lead researcher Mark Loeb, a professor of pathology and molecular medicine at McMaster who leads a group that has published high-profile studies on infectious disease and vaccine effectiveness.
Researchers are recruiting participants 18 to 24 years old for the trial. Participants will be randomly assigned to receive either a nosode, a placebo or a vaccine. The researchers will take blood samples to look for changes in antibody levels for diphtheria, pertussis, tetanus, mumps and measles. The study will be blinded, meaning that the researchers and participants will not know who received which treatment.
Loeb said it is unclear when the trial will be complete, but he said he hopes that the results add to the conversation about the effectiveness of homeopathic remedies such as nosodes.
But Timothy Caulfield, a Canada research chair in health law and policy at the University of Alberta, said the trial sets a troubling precedent and adds a false air of legitimacy to homeopathy.
"It's like studying flying carpets," Caulfield said. " It's so scientifically implausible that I worry that the only outcome of this, regardless of the findings of this study, is the legitimization of homeopathy."
Nosodes are homeopathic products promoted as safer alternatives to traditional vaccines by some naturopaths and homeopaths in Canada. They are made by taking bodily fluids from an individual infected with a particular ailment and diluting it until there is no active ingredient left. Homeopaths argue that water has a memory, which enables nosodes to protect against disease even though they contain no active substance.
While many nosodes have been approved for use by Health Canada, the department has said repeatedly that they should not be marketed as vaccines because there is no evidence to back their use in this way.
Despite the strong safety record of vaccinations, many continue to worry that they are dangerous and possibly linked to conditions such as autism. Many of those concerns stem from the work of disgraced former gastroenterologist Andrew Wakefield, who published a misleading study suggesting a link between the measles, mumps and rubella vaccine and gastrointestinal and behavioural problems.
Wakefield was being paid by lawyers involved in a lawsuit against vaccine manufacturers and some of the 12 children involved in the study were also part of the lawsuit. No credible scientific research has been able to replicate his findings, which were formally retracted by The Lancet in 2010.
But the impact of his work continues to be felt. A national survey conducted last year found that one in four Canadian parents believe that vaccines cause autism or question whether they do. Across Canada, many naturopaths and homeopaths continue to promote the idea that vaccines are dangerous and use their websites to encourage parents to question the need for vaccines, even though they are not trained or qualified to discuss vaccination with patients.
A study published on Monday in the journal Pediatrics found that children in the United States who used complementary and alternative medicine, including herbal remedies and acupuncture, were less likely to have been vaccinated against the flu.