Who is tweeting about vaccines?

During the period between October and December 2016, we used our algorithm to find out the most relevant Twitter influencers about vaccines. We performed a multilevel study to categorize the accounts and to identify the most relevant hashtags.

We analysed 869 accounts and categorized 373 of them:

  • 85 belonged to health professionals (47 doctors, 15 paediatricians, 14 researchers, 6 epidemiologists and 3 healthcare assistants)
  • 47 were media outlets
  • 32 belonged to politicians
  • 4 were public organizations

Public institutions (i.e. White House, WHO, CDC, Gates Foundation), politicians and media (i.e. Fox News) were the most popular accounts. Organisations and charities were highly represented too. Among personal accounts, Nancy Pelosi, Democrat spokesperson at the US Congress, has the highest number of followers (900K), followed by Jake Tapper (CNN journalist, 500K) and Jakaya Kikwete (former Tanzania president, actually involved in the promotion of vaccination campaigns). Ten accounts declared a family history related to supposed vaccine injury.

Most of the users used hashtag to describe their activity on Twitter, the most relevant being #CDCwhistleblower. This hashtag is strongly connected with the movie VAXXED released on 2016 and directed by Andrew Wakefield. This is a well-known name: in 1998, Wakefield published a study in The Lancet suggesting that vaccines caused autism. In 2010, the study was retracted following the report of serious ethical violations by Wakefield himself, whose UK medical license was then revoked. The movie is based on a conspiracy theory according to which there is a CDC whistleblower who revealed that the CDC manipulated the results of a study showing a link between vaccines and autism. The study – performed by two CDC employees, Frank De Stefano and William Thompson – confirmed that there is no evidence that children with autism were more likely to have received their first MMR vaccine earlier than neurotypical controls. However, a review of the same data led to a different conclusion, according to its author Brian Hooker: there is a strong correlation between MMR vaccine and autism in black male children who received the shot within their first 36 months of life. The Hooker’s paper was retracted too, due to “undeclared competing interests on the part of the author” and post-publication “concerns about the validity of the methods and statistical analysis”. Moreover, Thompson – the whistleblower – was not aware of being recorded over the phone and never watched the movie before its release. Nevertheless, the anti-vaccine movement continues to consider this story as a clear proof of public health institutions attempts to hid the truth about vaccines.

Following #CDCwhistleblower, our analysis found other relevant hashtags, as shown in the following table:

Geographical distribution

It is interesting to note that 52 users described themselves as a mom, while 28 as a dad. Among medical conditions explicitly cited in the accounts, we found 6 references to cancer and autism.


Debora Serra

MMLAP and other EU Projects

Health system analysis to support capacity development in response to the threat of pandemic influenza in Asia
Making society an active participant in water adaptation to global change
Public Participation in Developing a Common Framework for Assessment and Management of Sustainable Innovation
Engaging all of Europe in shaping a desirable and sustainable future
Expect the unexpected and know how to respond
Driving innovation in crisis management for European resilience
Effective communication in outbreak management: development of an evidence-based tool for Europe
Solutions to improve CBRNe resilience
Network for Communicable Disease Control in Southern Europe and Mediterranean Countries
Developing the framework for an epidemic forecast infrastructure
Strengthening of the national surveillance system for communicable diseases
Surveillance of vaccine preventable hepatitis
European monitoring of excess mortality for public health action
European network for highly infectious disease
Dedicated surveillance network for surveillance and control of vaccine preventable diseases in the EU
Modelling the spread of pandemic influenza and strategies for its containment and mitigation
Cost-effectiveness assessment of european influenza human pandemic alert and response strategies
Bridging the gap between science, stakeholders and policy makers
Promotion of immunization for health professionals in Europe
Towards inclusive research programming for sustainable food innovations
Addressing chronic diseases and healthy ageing across the life cycle
Medical ecosystem – personalized event-based surveillance
Studying the many and varied economic, social, legal and ethical aspects of the recent developments on the Internet, and their consequences for the individual and society at large
Get involved in the responsible marine research and innovation
Knowledge-based policy-making on issues involving science, technology and innovation, mainly based upon the practices in Parliamentary Technology Assessment
Assessment of the current pandemic preparedness and response tools, systems and practice at national, EU and global level in priority areas
Analysis of innovative public engagement tools and instruments for dynamic governance in the field of Science in Society
Public Engagement with Research And Research Engagement with Society
Computing Veracity – the Fourth Challenge of Big Data
Providing infrastructure, co-ordination and integration of existing clinical research networks on epidemics and pandemics
Promote vaccinations among migrant population in Europe
Creating mechanisms for effectively tackling the scientific and technology related challenges faced by society
Improve the quality of indoor air, keeping it free from radon
Improving respect of ethics principles and laws in research and innovation, in line with the evolution of technologies and societal concerns
Investigating how cities in the West securitise against global pandemics
Creating a structured dialogue and mutual learning with citizens and urban actors by setting up National Networks in 10 countries across Europe
Identifying how children can be change agents in the Science and Society relationship
Establishing an open dialogue between stakeholders concerning synthetic biology’s potential benefits and risks
Transparent communication in Epidemics: Learning Lessons from experience, delivering effective Messages, providing Evidence