WHAT WAS CLAIMED
Tetanus vaccines provide little benefit and vitamin C is an effective alternative.
OUR VERDICT
False. Tetanus vaccines have significantly reduced tetanus cases and deaths and there is no quality evidence that vitamin C is an effective treatment.
AAP FACTCHECK - A viral social media video casts doubt on the benefit of receiving the tetanus vaccine, among a slew of dubious claims about the infection itself and the vaccines used to fight it.
Tetanus cases and deaths have fallen dramatically since the introduction of the vaccine, and experts say there is no good evidence vitamin C works as a treatment, as is claimed in the video.
The clip, which has been viewed at least 3.7 million times, makes a range of claims about tetanus vaccines and their risks and benefits, including:
- Your risk of contracting tetanus in general is "extremely low" unless you're "working on a farm or walking barefoot through manure".
- Vitamin C is a proven treatment for tetanus.
- Getting a tetanus booster after receiving a high-risk wound won't help you fight infection because of the time it takes to develop antibodies.
- Getting the tetanus vaccine can cause a fatal reaction in those with milk allergies.
- Tetanus vaccines are "usually made from rotting organs".
- There's no difference in the level of protection between those who receive a tetanus booster every 10 years and those who receive one every 30 years.
Experts told AAP FactCheck many of these claims are false or misleading and based on inaccurate or outdated information.
VACCINE SUCCESS
Tetanus is caused by a bacteria that produces a neurotoxin and lives in soil and manure - not rust, as the video correctly states - and can be introduced into the body through a wound.
The Australian health department explains tetanus can occur after seemingly trivial injuries, such as a prick from a rose thorn, but certain wounds carry higher risk, e.g. deep wounds contaminated with foreign objects, including soil and dust.
As most people in Australia are routinely vaccinated, tetanus cases are rare, with a rate of 0.02 cases per 100,000 people.
The unvaccinated are most at risk.
After vaccines became widely available in developed countries in the 1940s and '50s, the number of tetanus cases and deaths declined markedly.
More than 60 people died from tetanus annually before the introduction of childhood vaccination in Australia in 1953, according to the Australian Institute of Health and Welfare (page 2).
That has now declined to less than one death a year.
In the US, the number of tetanus-related deaths has declined by more than 99 per cent since the 1940s, when routine vaccination began, while the number of cases declined by 95 per cent, from about 500 a year to fewer than 40, according to the US Centers for Disease Control and Prevention (CDC).
Of 67 tetanus cases in the US with known vaccination status between 2013 and 2023, only 16 (24 per cent) were fully vaccinated.
Helen Petousis-Harris, a vaccinologist at the University of Auckland, told AAP FactCheck tetanus vaccines provide protection against a potentially fatal disease.
She noted routine vaccination had virtually eliminated tetanus as a cause of death in combat casualties, which was once a major killer in war.
Health New Zealand explains there were 12 cases of tetanus among US soldiers in World War II, when vaccination in the military was routine, a rate about 30 times lower than in World War I, when vaccines weren't available.
"The vaccine's benefit is not hypothetical - it is one of the most successful public health interventions in modern medicine," Associate Professor Petousis-Harris said.
RISK NOT JUST FOR FARM WORKERS
Contrary to the video's claims, Assoc Prof Petousis-Harris said, the risk of tetanus isn't limited to those working on farms or walking barefoot through manure.
"The disease typically follows minor wounds or injuries," she said, "often in non-rural or everyday settings, such as garden work, home repairs … rather than from farm or manure exposure alone."
Though cases are rare, thanks to vaccination, she said they're often severe when they do occur.
In Australia, about two per cent of people who contract tetanus die. Without medical treatment, however, almost all those infected die, according to the CDC.
Louise Thwaites, a tetanus researcher at the Centre for Tropical Medicine and Global Health, said tetanus spores, which lead to the disease, have been found throughout the environment, though particularly in soil and manure.
The spores are also highly resistant, she said, meaning normal cleaning doesn't necessarily sterilise them.
LOW-QUALITY EVIDENCE FOR VITAMIN C TREATMENT
The video recommends taking vitamin C to treat a tetanus infection rather than vaccination, referring to a 2013 Cochrane Review.
The review found there was only a single trial that investigated the efficacy of vitamin C as a tetanus treatment, which did find a significant reduction in death rates.
However, the trial was not rigorous and had few controls for biases, so the review concluded "this result must be interpreted with caution and vitamin C cannot be recommended as a treatment for tetanus on the basis of this evidence", while recommending new trials.
Assoc Prof Petousis-Harris agreed there's limited and low-quality evidence for using vitamin C as a tetanus treatment, pointing out that although it's great for scurvy, it's not a substitute for proven therapies for tetanus and shouldn't be presented as an alternative.
"Relying on vitamin C for tetanus is like using orange juice to treat a gunshot wound," she said.
Prof Thwaites also referred to the Cochrane Review and said vitamin C was not recommended as an effective treatment.
ADDITIONAL SHOT CAN HELP
Another of the video's claims is that getting "an additional shot" wouldn't help because it takes two to seven weeks to develop antibodies: "So, if you're already infected, it's too late."
Experts, however, told AAP FactCheck that while it takes a number of days for a tetanus booster to increase antibodies, healthcare providers can administer a "passive immunisation" injection to provide faster protection.
Both the CDC and World Health Organization (WHO) say tetanus infection incubation period is three to 21 days, with the CDC stating the average is about eight days.
Antibody concentrations after a tetanus booster, meanwhile, begin to increase after about four days, according to a 2016 Harvard paper (p4) and the WHO (p20).
A 2011 study published in Clinical Infectious Diseases found antibody levels increase noticeably after five to seven days, and peak after about 14 days.
Terry Nolan, an expert in vaccines at the University of Melbourne, told AAP FactCheck tetanus vaccination is not intended to treat an infected wound, which the social media video suggests.
Instead, "immune globulin" (immunoglobulin) injections, which contain antibodies that fight tetanus directly, can be administered, providing rapid protection.
"If someone who's never been vaccinated, or who's immune compromised, has a tetanus-prone wound, they should receive tetanus immunoglobulin," Professor Nolan said.
Frank Beard, a vaccination expert at the University of Sydney, told AAP FactCheck tetanus immunoglobulin provides high levels of antibodies to cover the initial two-week period before antibodies produced by the person's own immune system peak.
Australian guidelines recommend administering tetanus immunoglobulin for those who have immune deficiency or have received fewer than three vaccine doses, or have an uncertain vaccine history, and have a wound considered not clean and more than minor.
Professor Thwaites also noted tetanus infection doesn't lead to future immunity, whereas vaccination can provide protection against developing tetanus in future.
MILK ALLERGIES CLAIM OVERSTATED
The video also states those who have milk allergies are at risk of a fatal reaction to the vaccine "yet most people are never warned about this".
The video includes an image of a 2011 letter to the editor in the Journal of Allergy and Clinical Immunology, which documents an investigation into whether there was a link between severe milk allergies and anaphylaxis from the booster vaccine in eight patients at a single practice.
Casamino acids, from the cow's milk protein casein, are involved in the production of tetanus vaccines, the letter explains.
The researchers confirmed the presence of milk proteins in the tetanus vaccines analysed, and discovered the patients who had a reaction to the vaccine also had a milk allergy. None of the cases were fatal.
The letter concludes by claiming vaccines developed using milk proteins may present a risk to those with severe milk allergies.
The Facebook video also includes an image of a 2022 journal case report that claimed residual cows' milk proteins in a Japanese encephalitis vaccine were the cause of a case of anaphylaxis in Japan.
However, Assoc Prof Petousis-Harris said there is no robust evidence that those with milk allergies are at an increased risk of anaphylaxis following the tetanus vaccine.
Australia's Therapeutic Goods Administration told AAP FactCheck casein hydrolysate is not a listed ingredient but is used in the production of the tetanus vaccine and, as such, there's a possibility it might be present in trace amounts in the final product.
Across more than 50 years, there have been just 205 reports of anaphylactic reaction, anaphylactoid reaction or anaphylactic shock, none of which were associated with a fatal outcome, the TGA said.
NZ medical regulator Medsafe similarly told AAP FactCheck that no NZ-approved tetanus vaccines contain any form of milk protein as an ingredient, but trace amounts may remain if used in the manufacturing process.
It also has not received any reports of fatal anaphylaxis after administration of any tetanus vaccines, with just 35 reports of an anaphylactic reaction.
ROTTING ORGANS CLAIM 'INFLAMMATORY MISCHARACTERISATION'
The video claims tetanus vaccines "are usually made from rotting organs".
Assoc Prof Petousis-Harris called this "an inflammatory mischaracterisation".
Though some tetanus vaccines use a medium derived from animal products, including beef heart, to grow the initial bacteria culture, these ingredients are "purified, sterilised and rigorously tested", she said.
"Referring to them as 'rotting organs' is inaccurate."
BOOSTER BENEFITS
The video describes the US recommendation to get a tetanus vaccine every 10 years as "a vaccine schedule joke", as studies have found vaccination every 30 years provides identical protection.
It refers to a 2016 Clinical Infectious Diseases article, which found tetanus antibody levels halved every 14 years in patients, providing most people with protection 30 years after vaccination.
It noted those older than 60 had more marked declines in antibody levels, likely due to declining immune function with age.
The study also noted that between 2008 and 2012, all of the 14 tetanus-related deaths in the US were in patients who received fewer than three tetanus vaccines, or had unknown vaccine history, while all cases in fully vaccinated individuals survived.
Assoc Prof Petousis-Harris said neither New Zealand nor Australia recommend routine 10-year tetanus boosters except for those at higher risk due to travel or occupation.
In Australia, health authorities recommend a booster at the age of 50 and again at 65 for those who haven't had a booster in the last decade.
People travelling to countries with "difficult to access" health services are recommended to get a booster every 10 years, and travellers at greater risk of tetanus-prone wounds to get boosted every five years.
NZ health authorities recommend a booster at ages 45 and 65 unless you've had a booster in the past decade.
The 10-year schedule recommended by US authorities is precautionary, Assoc Prof Petousis-Harris said, but not because shorter intervals are strictly necessary in every case.
"Leaving people potentially at risk of tetanus disease is not worth the risk.
"It is a very serious disease, and treatment is long, painful, and very expensive."
AAP FactCheck is an accredited member of the International Fact-Checking Network. To keep up with our latest fact checks, follow us on Facebook, Instagram, Threads, X, BlueSky, TikTok and YouTube.
