PONE-D-20-39758

The anti-vaccination infodemic on social media: a

behavioral analysis

PLOS ONE

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Reviewer #2: Yes

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Reviewer #2: Yes

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Reviewer #1: The anti-vaccination infodemic on social media: a behavioral analysis

This article is well-written, informative and based on a robust methodology.

I have following comments:

- Authors may further discuss their results relying on recent studies on the same topic: Vaccines (Basel). 2021 Jan 7;9(1):E28. and PLoS One. 2020 Oct 8;15(10):e0239826.

- Authors can also refer to and discuss other infodemiological studies related to attitudes towards vaccines: J Prev Med Hyg. 2016;57(1):E47-50. and Hum Vaccin Immunother. 2017 Feb;13(2):464-469.

- Authors could suggest some ways to fight against unsubstantiated vaccin hesitancy and "fake news", and to provide more accurate informations (the same social media could be exploited as a source of accurate health-related informations, as shown in other fields; see for instance: Mult Scler Relat Disord. 2018 Oct;25:175-178. - Mult Scler. 2018 Nov;24(13):1657-1664 - Interact J Med Res. 2017 Sep 27;6(2):e18. - An Acad Bras Cienc. 2019 Feb 14;91(suppl 1):e20180149)

- Incidentally, regarding the influence of Donald Trump on vaccine misinformation on Twitter, something similar has been observed in other fields and is worth mentioning (Clin Colon Rectal Surg. 2017 Sep;30(4):270-276. ). It is very well known that celebrities´statements on health can deeply influence the online searches for health-related information; this is not necessarily bad, but could (and should) be used to improve public health (for instance by involving these celebrities as testimonals: J Public Health (Oxf). 2015 Sep;37(3):555-6

Reviewer #2: Really good and interesting work! I suggest only specify Donald Trump as ex President, according to last results from presidential election in USA recently concluded. Please, add some comments focused on possible impact of social media on institutional decisional pathway

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Reviewer #1: No

Reviewer #2: Yes: Giovanna Borriello

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The anti-vaccination infodemic on social media: a behavioral analysis

PONE-D-20-39758R1

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Kind regards,

Luigi Lavorgna

Academic Editor

PLOS ONE

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