Nasal flu vaccines don’t contain ‘mice bred streptococcal bacteria’

22 December 2022
What was claimed

The nasal flu vaccine given to children contains streptococcal bacteria and aluminium, and is linked to the outbreak of deaths from strep A.

Our verdict

False. The flu vaccine does not contain streptococcal bacteria or aluminium. There is no proven link between the deaths from strep A and the vaccine.

What was claimed

Covid-19 tests cause cancer due to being “laden” with ethylene oxide.

Our verdict

Ethylene oxide is carcinogenic in large enough exposures, but the amount on Covid test swabs and the length of time we are exposed to them poses minimal risk.

What was claimed

Face masks cause deoxygenation.

Our verdict

Wearing face masks continually for long periods of time can lead to slight changes in oxygen and carbon dioxide levels but not enough to be clinically significant.

A Facebook post shows a screenshot of a news story about strep A deaths in the UK, captioned with false claims about flu vaccines, Covid-19 tests and masks.

The caption says: “This is what happens when you spray ‘Mice Bred’ Streptococcal bacteria laden with nano particulate aluminum up the noses of children in the form of the ‘Flu Nasal Spray’.

“The constant poking of the cancer-causing, Etheline oxide laden Covid tests of course won’t of helped, nor Would the wearing of the oxygen depleting face Nappy’s [sic].”

These claims are not true.

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Flu vaccine doesn’t contain strep A or aluminium 

We have fact checked several false claims about the nasal flu vaccine given to children this year, with several viral social media posts claiming a link to the outbreak of strep A, from which 21 children in England have died.

The nasal flu vaccine has been given to schoolchildren since 2013, with the number of years included in the program increasing year on year from just year 1 pupils, to now all primary school children and some in secondary schools. 

The poster falsely claims that the “Flu Nasal Spray” contains streptococcal bacteria from mice. The term streptococcal refers to a group or “genus” of bacteria defined by their microscopic appearance. Within this genus are many different species—such as group A strep (which causes infections such as scarlet fever or more serious, invasive infections), group B strep (which is linked to infections in childbirth) and strep pneumoniae (a cause of chest infections).

If the Facebook post is claiming that the nasal flu vaccines contain strep A, this is not true. Dr Simon Clarke, associate professor in cellular microbiology at the University of Reading previously told Full Fact: “The claims that it [the nasal flu vaccine] has group A strep bacteria in it are just nonsense. It would fail its quality control if that was the case.” 

The claim that the vaccine contains “Mice Bred” streptococcal bacteria may come from a study published in the scientific journal mBio which found higher concentrations of streptococcus pneumoniae in the nasal passages of mice after giving them a nasal flu vaccine. However, the strep A bacteria was not the one being studied, and the mice had no increase in severe disease or death. We have written about this previously.

The strep A deaths have not been found to be linked to the flu vaccine, which a new report from the UK Health Security Agency (UKHSA) suggests may actually protect against strep A to some extent. 

The pre print article looks at the difference in strep A infections between areas ‘piloting’ the nasal flu vaccine program (by offering the vaccine to all primary school children) and those that introduced the vaccine incrementally through year groups. This essentially compared areas with more children vaccinated to those with less. 

The study found a significant reduction in strep A infections, scarlet fever and iGAS infections for the pilot areas for school aged children, with no difference in scarlet fever or iGAS rates.

The Facebook post also claims the nasal flu vaccine contains aluminium. The full list of ingredients of the Fluenz Tetra nasal spray used in the UK vaccine program does not include aluminium or any substances containing aluminium.

Covid-19 tests don’t cause cancer

The post also claims that the “constant poking of the cancer-causing, Etheline oxide laden Covid tests of course won’t of helped [sic]”.

We have written before about false claims on the effect of ethylene oxide on Covid tests. Ethylene oxide is a colourless gas that is used to sterilise medical equipment around the world and, although overexposure can be dangerous, its use does not make medical products like lateral flow tests unsafe. 

Ethylene oxide is an important industrial chemical used in the production of various consumer goods, with 0.05% of global production used to sterilise items, including medical equipment, dressings and swab tests. The majority of the rest is used in chemical production. 

The International Agency for Research on Cancer has stated that ethylene oxide is carcinogenic to humans. However, chronic exposure at sufficient levels is required for any significant risk to occur. Exposure limits are set by the Health and Safety Executive in the UK to reduce the risk to workers who may come into contact with the chemical.  

Ethylene oxide is used to sterilise swabs used in Covid tests. After sterilisation, ethylene oxide must be removed from the swabs, and the manufacturer has to confirm that any residual level is below the required international standard, verified by an independent third-party. The Department of Health and Social Care previously confirmed with Full Fact that a minimal amount of ethylene oxide is used for sterilisation of the swabs—just 1-2μg (millionths of a gram) per gram.

The Medicines & Healthcare products Regulatory Agency states that exposure to ethylene oxide via Covid swabs leads to limited time exposure and poses “minimal risk”. 

The UKHSA states that “Any traces of ethylene oxide remaining in medical devices (for example lateral flow devices) after sterilisation are below limits that would be considered hazardous to health and comply with international standards.”. 

So while heavy exposure to the chemical itself is “cancer causing”, the levels of exposure to it from using Covid swabs as directed is extremely unlikely to be.

Full Fact is not aware of any evidence linking Covid swab usage to strep A infections. Indeed by sterilising the swabs before use, ethylene oxide makes them less likely to spread infections.

Masks and oxygen levels

The final claim in the post refers to “oxygen depleting face nappies” which would appear to be a claim that wearing face masks leads to lower oxygen levels. The effect of face masks on oxygen levels has generally not been found to be clinically significant, with some small studies done in various groups of people.

We have written before about false claims that face masks are harmful.

A study published in the Journal of the American Medical Association involving 25 elderly people showed no drop in SpO2 (a measure of blood oxygen levels) when they wore surgical face masks while doing minimal physical activity. 

Another involved 14 healthy young people, and had them use an exercise bike to exhaustion on three occasions, with no mask, a cloth mask, and a surgical mask. The researchers found no effect on SpO2 or muscle oxygenation levels, nor any impact on exercise performance.

Another study of 50 hospital workers—around a third of whom had some underlying disease—found masks “did not impair oxygenation or ventilation among 50 adults at rest or during physical activity”. It added: “No episodes of [low blood oxygen] or [high blood CO2 levels] occurred with either cloth or surgical masks, both at rest and while walking briskly.”

The BMJ has published two studies in this area. One looked at 36 patients with connective tissue disease associated interstitial lung disease (CTD-ILD)—wherein a systemic issue with connective tissue causes scarring in the lungs and serious breathing issues. In this group, wearing face masks did reduce the amount of distance they could walk over six minutes and their SpO2 during the activity. The study authors stressed that they ”should not be misinterpreted as implying face masks should not be used in patients with CTD-ILD”. 

The other study had 11 healthy teenagers do the same six-minute walking test and found no significant difference in either oxygen levels or distance walked when wearing surgical masks.

Full Fact is not aware of any evidence to suggest the wearing of face masks is linked to strep A infections, nor that it increases the risk of bacterial infections in general, although mask wearing can cause a sore throat.


Image courtesy of Annie Spratt

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