Doctors warn of no evidence suggesting homeopathic nosodes should replace vaccines.

Homeopathy and modern Western medicine are often at odds, especially when it comes to determining the best way to prevent disease.

Modern medicine relies on prophylactic vaccines while homeopathy champions “vaccine alternatives.”

Known as nosodes, these alternatives are diluted bacteria or viruses from infected human tissue that contains these organisms. Nosodes may be formulated by taking pus or feces from people suffering diseases such as tuberculosis or anthrax, then sterilizing and repeatedly diluting it until very few or no microbes remain. Nosodes are typically sold as jars of small pellets.

Nosodes are used by some people distrustful of modern vaccines, despite overwhelming evidence that conventional vaccines are effective and safe, and little evidence that nosodes are either.

The use of nosodes has become so common the Canadian Pediatric Society (CPS) launched a public health campaign to remind parents, “‘Nosodes’ are no substitute for vaccines.”

In a position statement issued in May, the CPS recommended the labeling on nosodes to reflect, “[s]cant evidence in the medical literature for either the efficacy or safety of nosodes, which have not been well studied for the prevention of any infectious disease in humans.”

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In their position paper, CPS officials outline a limited number of studies addressing nosodes’ effectiveness. None of those include cases of measles, mumps, rubella, diphtheria, tetanus, polio, hepatitis B, chickenpox, whooping cough, meningitis, or invasive bacterial infections.

“Nosodes have not been studied for the prevention of any of these infections,” the CPS states.

A 1999 study in mice looked at how nosodes prevented infection against tularemia, an infectious bacterial disease in animals that can be transmitted to humans. In 15 trials, nosodes offered some protection for 22 percent of mice while 100 percent were protected by vaccine.

Still, nosodes can be bought online as remedies for or prevention of common and complicated infections. The site, for example, provides nosodes for some of the following infections: anthrax, cholera, E. coli, hepatitis, the human papillomavirus (HPV), leprosy, malaria, measles, rabies, salmonella, chicken pox, and small pox.

The site carries a disclaimer that notes “homeopathy is not a substitute for medical diagnosis and treatment” and their products are “not intended to diagnose, mitigate, prevent, treat, or cure any symptom or disease as defined by the [U.S. Food and Drug Administration].”

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Dr. Jordan Tishler, a Harvard-educated physician who also uses alternative medicines in his practice in Massachusetts, said there isn’t enough evidence that homeopathic medicine works for any condition, let alone as an alternative to vaccines.

“Vaccines really have been a game-changer,” he told Healthline.

Vaccines are strongly recommended by the medical community for a host of ailments including HPV, a virus that causes cervical cancer. When it came to deciding whether to vaccinate their daughter, Tishler and his wife, a physician as well, made the easy choice.

“We vaccinated her,” he said. “There’s no question in my mind that the science behind these vaccines is strong and conclusive.”

Still, Tishler isn’t exactly on board with all vaccines — namely chicken pox and the flu vaccine — but that doesn’t mean he thinks nosodes are an effective alternative.

“Where we are historically at the moment, most people today don’t understand how their daily lives are protected by vaccines,” he said.

Dr. Amesh A. Adalja, an infectious disease physician at the University of Pittsburgh Medical Center, says nosodes have not been proven to prevent infections, especially when compared to the evidence in support of vaccines.

“The data supporting the beneficial power of existing repertoire of vaccines is robust and nosodes come nowhere near this level of protection,” he told Healthline. “Vaccines are rigorously tested substances that are put through randomized controlled trials in order to establish their efficacy, safety, and dose. Nosodes have no such evidence backing them and the few studies that show possible benefit were not conducted with the same level of meticulousness.”

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Jennifer Schmid, a registered nurse and traditional naturopath practicing in California, said most physicians are not educated properly about vaccines or communicable diseases.

“Instead, they are taught to use fear as a means to coerce patients and families into vaccinating, which is definitely not without risk,” she told Healthline. “Based on the data, homeopathy is an effective way both to prevent illness and to stimulate the immune system back toward health during a disease, without any untoward side effects or risks of adverse reactions, such as encephalopathy after measles vaccine.”

Schmid, however, didn’t provide large-scale studies to support those claims when requested.

Vaccines do sometimes have adverse side effects. Most of these are mild and subside within a few days, according to the CDC.

Still, some parents choose to not vaccinate their children for personal reasons. Many believe a chemical used in vaccines, thimerosal, causes autism, a claim first started in 1998 on research now deemed fraudulent.

The CDC maintains that vaccines do not cause autism, neither do their ingredients. The myth-fighting website Snopes debunked claims that the CDC suppressed evidence to the contrary.

But the seeds of distrust regarding vaccines are often planted so deep that the light of new information does little to change misperceptions. In particular the measles, mumps, and rubella (MMR) vaccine can’t seem shake the negative chatter.

A study published in the journal Pediatrics found presenting parents with the CDC’s information about the MMR-autism misconception — using pictures or stories of children infected with measles — did nothing to change their intentions to not vaccinate their children.

There are some people who should not be vaccinated. For example, the (MMR) shouldn’t be given to children who are allergic to it, have a disease that affects their immune systems, or are undergoing cancer treatments.

These children are usually protected by herd immunity. That’s when a large percentage of the community is protected against a pathogen so it cannot spread as widely or quickly.

While vaccines are the backbone of herd immunity, homeopathic treatments “destroy herd immunity,” Adalja said, because nosodes don’t actually help a person develop resistance.

“They are not alternatives to vaccines for any group, even those too young or unable to receive a vaccine,” he said. “Vaccines have literally changed the world for the better. Major advances in lifespan occurred because of vaccines — a safe and efficacious technology for which there is no substitute.”

The rise in the use of nosodes “has more to do with the phenomenon of the general public losing the ability to think objectively, weigh evidence, and make reasoned judgments,” Adalja said. “There is no excuse for doubting the efficacy of vaccines.”