A new type of 'vaccine scepticism' has been uncovered by researchers at Lancaster University, who examined a nine-million-word corpus of tweets looking at vaccine comparisons and evaluations.
They focused on claims that some vaccines, notably those against COVID-19, were not perceived by some people posting on Twitter/X as 'proper' vaccines.
Based on their findings they suggest it would be helpful for future public health messaging to address potential confusion among the public about what counts as a vaccine.
This new research, led by Professor Elena Semino, of Lancaster University, working with the researchers from the UK Health Security Agency, as well as at UCL and Georgetown University, is published in the March edition of Elsevier's 'Vaccine X' Journal.
The COVID-19 vaccines were often evaluated negatively compared with vaccines like MMR due to the public perceiving the COVID-19 vaccines as having low effectiveness.
This perception of low effectiveness led some Twitter/X 'posters' to claim that COVID-19 vaccines are not vaccines.
This 'vaccine is not a vaccine' is a new, previously unreported type of vaccine-specific scepticism, and it arose only during the COVID-19 pandemic. However, it might, according to the researchers, also apply to the flu vaccine.
While it is well-known that vaccine hesitancy can be vaccine-specific, researchers do not know very much about how and why people spontaneously evaluate different vaccines in comparison with one another, or the implications of these comparisons for vaccine attitudes.
The nine-million-word body of words or 'corpus' created by the researchers consists of tweets containing references to the MMR vaccine posted between 2008 and 2022.
First, tweets posted in 2020-2022 and also containing references to COVID-19 were examined for vaccine-specific evaluation and vaccine-related topic.
Then, the whole corpus was analysed for tweets that contained expressions that challenged the status of a vaccine as a vaccine - for example 'not a vaccine', and the use of 'shot' in contrast with 'vaccine'.
The researchers found that in 2020-2022, tweets mentioning COVID-19 alongside MMR had an increasing tendency to compare the COVID-19 vaccines unfavourably with the MMR vaccine, based on the perceived low effectiveness of the COVID vaccines against infection.
For example, one Twitter/X poster said: "It's not even a real vaccine. You can catch covid and also spread it if you are vaccinated. You don't catch polio or MMR after you are vaccinated."
The research also showed a perceived contrast in 2020-2022 between the words 'shot' and 'vaccine', with the 'shot' being described as an 'inferior' medical intervention and associated with COVID 19.
The researchers also noted that scepticism about the status of any vaccine being a real vaccine was very rarely expressed on Twitter before 2020.
"Overall, the new form of vaccine specific scepticism we have identified is relevant for any current or future vaccines that primarily modify disease rather than prevent infection," says the research.
Lead author Professor Semino, from Lancaster University's Linguistics Department, ranked third in the world (QS World University Rankings by Subject 2024), said: "The finding that some people on Twitter/X question the status of the COVID-19 vaccines as vaccines was unexpected. It shows that it is important to explain how different vaccines work, depending on the nature of the disease."
Examples of posts from the data include:
"It's not even a real vaccine. You can catch Covid and also spread it if you are vaccinated. You don't catch polio or MMR after you are vaccinated."
"That's why it [the COVID-19 vaccine] shouldn't be called a vaccine, but a shot like the flu shot, yearly. MMR were actual vaccines to prevent measles and rubella. So was the polio vaccine."
"How about we start with the fact that it's not a vaccine, it's a therapeutic. True vaccines immunize you from the virus. The COVID 'vaccine' still allows you to catch COVID just with lesser symptoms. Not the same with polio, MMR, etc."
"Vaccine: polio, MMR, smallpox. You don't have to get them again and you won't get the disease. Shot: tetanus, flu, Covid. You have to keep getting them because they aren't a cure because there is no cure, especially for a coronavirus. Stop calling it a vaccine. It's a shot."
