# Health Misinformation in Social Networks: A Survey of Information Technology Approaches
## 1 Introduction  
The spread of misinformation online, most commonly known as fake news, is an important issue that has become more pronounced in the last two decades due to the prevalence of social media. Platforms like Twitter, Reddit, and Facebook have been commonly identified as the main channels for propagating misinformation and have been criticized for not acting on addressing the conditions that permit the circulation and amplification of false information [1]. Such misinformation includes false claims and non-fact-checked news items, which originate from sources of questionable credibility [2]. The problem of misinformation becomes critical when it pertains to healthcare and health issues, since it puts lives and public health at risk. One of the first cases of widely spread misinformation in the medical domain is the falsehood that the MMR vaccine(measles, mumps, and rubella) causes autism [3]. The falsehood originated from a fraudulent article titled \"Ileal-lymphoid-nodular hyperplasia, non-specific colitis, and pervasive developmental disorder in children\" published in the prestigious _Lancet_ journal in 1998 [4; 5]. This study turned tens of thousands of parents against the vaccine, and as a result, in 2020, many countries, including the United Kingdom, Greece, Venezuela, and Brazil, lost their measles elimination status. In 2020, twenty-two years after publishing this study, _Lancet_ retracted the paper [6]. Examples of medical fake news that have spread on social media include the oncogenic effects of antihypertensive drugs, which caused several patients to stop using them, and misinformation about the Human Papillomavirus (HPV) vaccines, which resulted in half of the population in South Carolina not having completed the vaccination series [5; 7]. The issue of fake news was exacerbated during the recent COVID-19 pandemic, where it became clear that the enemy was not only the virus but also the abundance of misinformation leaked on social media and the web, even from prominent public figures, endangering human lives ([[https://www.europol.europa.eu/covid-19/covid-19-fake-news](https://www.europol.europa.eu/covid-19/covid-19-fake-news)]([https://www.europol.europa.eu/covid-19/covid-19-fake-news](https://www.europol.europa.eu/covid-19/covid-19-fake-news)), accessed on 2 November 2023). The extent of online health misinformation led the World Health Organization (WHO) to declare an \"infodemic\", that is, \"an overabundance of information--some accurate and some not--that makes it hard for people to find trustworthy sources and reliable guidance when they need it\" ([[https://www.who.int/health-topics/infodemic](https://www.who.int/health-topics/infodemic)]([https://www.who.int/health-topics/infodemic](https://www.who.int/health-topics/infodemic)), accessed on 2 November 2023). The repercussions of the infodemic as severe: it results in \"an increase in erroneous interpretation of scientific knowledge, opinion polarization, escalating fear, and panic or decreased access to health care\" [4], and it is detrimental to public health, impacting healthcare utilization and cost and medical non-compliance [8]. Indicatively, in a recent poll ([[https://debeaumont.org/wp-content/uploads/2023/03/misinformation-poll-brief-FINAL.pdf](https://debeaumont.org/wp-content/uploads/2023/03/misinformation-poll-brief-FINAL.pdf)]([https://debeaumont.org/wp-content/uploads/2023/03/misinformation-poll-brief-FINAL.pdf](https://debeaumont.org/wp-content/uploads/2023/03/misinformation-poll-brief-FINAL.pdf)), accessed on 10 December 2024), among 806 physicians, 3 out of 4 of the physicians said that medical misinformation has hindered their ability to treat COVID-19 patients. Half of them estimated that most of the information they receive from patients is misinformation, which also extends to areas such as weight loss, dietary supplements, mental health, and other vaccines. As a response to this wave of dangerous misinformation, there was a call to arms to construct tools for weathering the infodemic.