However, Facebook, the owner of Instagram, has not blocked the hashtag.
Prior to the ban, use of #naturalimmunity coincided with notions relating to a scientific study conducted out of Israel. The paper concludes that "natural immunity confers longer-lasting and stronger protection against infection, symptomatic disease and hospitalization caused by the Delta variant of SARS-CoV-2, compared to the BNT162b2 two-dose vaccine-induced immunity."
The study also highlights, "individuals who were both previously infected with SARS-CoV-2 and given a single dose of the vaccine gained additional protection against the Delta variant."
Managing director of social media agency Source PR, Louis Hill told Metro it was "counter intuitive to ban certain [hashtags] as it only provides further ammunition for the conspiracy theorists."
"Other than harmful, violent or hateful commentary, [banning hashtags is] damaging to our freedom of speech traditions and a very dangerous place if social media platforms start censoring views, conversations or opinions," he noted.
While it appears to be fighting misleading comments from anti-vaxxers, some fear it may just be encouraging them.
Managing director of social media agency Source PR, Louis Hill, told Metro.co.uk: ‘It’s counterintuitive to ban certain #s as it only provides further ammunition for the conspiracy theorists.
‘Other than harmful, violent or hateful commentary, it’s damaging to our freedom of speech traditions and a very dangerous place if social media platforms start censoring views, conversations or opinions.
‘It would set a precedent and be hard to come back for future discussions. It could also lead to people leaving the platform and further polarisation in the media as people seek different platforms that reflect or tolerate their views.’
While it may have its limitations and not last forever, natural immunity after catching and recovering from coronavirus is not a conspiracy theory.
Currently scientists think that people will have protection for Covid for about six months after contracting the virus after the immune system develops antibodies.
Proof of natural immunity shown by a positive PCR test result for the virus can be used for the NHS Covid pass to gain access to events with large crowds in the UK.
Nonetheless, anti-vaxxers sometimes argue that it is better to let younger and healthier people catch coronavirus and build up immunity.
Health experts warn this approach is irresponsible and still puts people at risk of serious illness, which may explain Instagram’s response.
In 2019, the platform announced it would begin hiding search results for hashtags that consistently return misinformation aiming to dissuade people from getting vaccinated.
At the time, Instagram’s global head of policy said: ‘If the hashtag was #vaccines1234, if it contained a high proportion of known vaccine misinformation, we would block that hashtag entirely.’