You may not have heard of Dr. Eli David, an Israeli artificial intelligence developer with a PhD in computer science, and co-founder of Marpai Health, a health-care company that uses machine learning to manage plans for insurers like Aetna.

But he proudly brags about being among the top 100 influencers on Twitter, currently placed higher than Cardi B and Greta Thunberg, according to ranking site Notus. (It is unclear exactly how Notus calculates rankings, which are based on an account’s “social capital”.)

David is wildly popular with COVID conspiracy theorists, who are drawn to his daily tweets mocking scientific experts, spreading doubt about the safety of the COVID vaccine, and ridiculing those taking precautionary measures, like wearing masks.

In the last month alone, David has repeated numerous talking points common among COVID skeptics. He has claimed the virus poses “almost zero” risk to young people, while the vaccine poses “major risks;” said the pandemic was “faked,” cautioned followers to never “believe in science,” suggested scientists and politicians who imposed COVID restrictions should “pay for their crimes;” and tweeted: “Covid is a deadly pandemic. It killed science, logic, evidence-based medicine, and common sense.”

But David is not only a Twitter celebrity among anti-vaxxers. He is also the co-founder of Marpai Health, a health-care company that manages self-funded employer health plans for Aetna, a major health insurer owned by CVS.

“Vaccine skepticism kills people. So having the founder of a health-care company associated with a movement that kills people raises some serious questions,” says Dr. Robert Field, a professor of health management and policy at Drexel University.

To analyze David’s social media reach, The Daily Beast partnered with the Center For Countering Digital Hate (CCDH), a non-profit that aims to counter online misinformation. Dr David’s tweets garner an average of 3.9 million views a day, researchers at the CCDH found. His follower numbers have ballooned during the pandemic, increasing 14-fold since the start of 2021.

In recent days, Elon Musk, Twitter’s new CEO, has interacted directly with David, replying to some of his posts about COVID with emojis. Musk himself courted controversy when he tweeted, “My pronouns are Prosecute/Fauci,” echoing a sentiment popular with anti-vaxxers, including David. Under Musk’s leadership, Twitter abandoned its COVID misinformation policy and reinstated formerly banned accounts, allowing COVID conspiracy theorists to flourish.

David’s involvement in Marpai Health began in Tel Aviv, where he co-founded the company with chairman Yotan Eitan and current CEO, Edmundo Gonzalez, in February 2019.

They named the start-up after the Hebrew word “marpeh” meaning “cure,” adding “AI” onto the end to emphasize their hope to harness artificial intelligence, according to ISRAEL21c.

“We are a technology-driven health-care payer which uses A.I. to predict and help prevent costly events for our members, and in turn lower our clients’ health-care costs,” Marpai wrote in filings with the Securities Exchange Commission. The company has a research and development wing, Marpai Labs, in Israel.

David became the company’s “chief science advisor.” He holds a PhD in computer science from Bar-Ilhan University in Israel, according to his website. One of his doctoral advisers was Nathan Netanyahu, a computer scientist who is the cousin of Israeli prime minister Benjamin Netanyahu.

“Marpai Health has been able to recruit and maintain top talent largely due to potential employees wanting to work with Dr. Eli David,” the company wrote in filings with the SEC.

In April 2021, Marpai Health entered the United States’ lucrative “third-party administrator” market, buying out Continental Benefits, a Florida-based company that already had agreements with Cigna and Aetna to handle self-insured employer plans, which means the employer bears the cost of any health claims and uses a Third Party Administrator (TPA), like Marpai Health, to process the claims. These plans are typically less regulated than traditional, fully insured plans.

“All of a sudden, this young Israeli startup with 15 developers in Tel Aviv became a TPA with about $20 million in annual revenue and 50,000 members receiving health-care services from us,” Eitan told ISRAEL21c.

The company went public in October 2021, raising $28.75 million.

“Dr. Eli (Omid) David is a lecturer in deep learning at Bar-Ilan University in Israel and a leading researcher in A.I. We believe his university connection as well as his reputation and previous work experience with other technology companies will help attract key deep learning talent to us,” the company wrote in filings with the Securities Exchange Commission, “We have developed six A.I. modules to predict chronic conditions and high-cost medical procedures.”

David has also founded two other AI-based businesses, Deep Instinct, a cybersecurity company, and Deep Cube, a machine learning company.

Edmundo Gonzalez, Marpai Health’s CEO, told The Daily Beast this week that he was unaware of David’s tweets, but emphasized that David has no involvement in the daily operations of the company and is not on the corporate board. He described David’s role as a “shareholder.”

He also denied that David had developed any of the company’s AI technology himself, despite calling him an “AI genius” to The Daily Beast, and instead said he was only responsible for recruiting developers.

However, David appears to hold considerable power in the company, according to documents filed with the SEC. In the filings, David is described as one of a small group of primary shareholders (including Marpai’s other co-founders, Eitan and Gonzalez) who would continue to “substantially influence” Marpai, even after it went public. “The Company will continue to be controlled by these shareholders,” the document states.

Gonzalez said the company subscribes to the scientific consensus on COVID, and covers treatments and vaccines.

“[David’s] views and expressions on social media are entirely his own, and not those of Marpai. He is not part of Marpai’s management team, nor is he a member of our board of directors,” Gonzalez told The Daily Beast.

Field says even if David is not involved in the day-to-day operations of Marpai Health, the connection between his public persona and a mainstream health-care company still raises concerns.

“This ties into the larger anti-vax movement which has caused a fair number of people to avoid vaccines, and some of them have died of COVID as a result, and some of them have spread COVID as a result,” Field says. “Is this another foot in the door of legitimate health care of the anti-vax movement?”

Marpai Health’s major client is Aetna, a health insurance company that was bought by CVS Health in 2018. The $69 billion CVS-Aetna deal was the biggest health-care merger in U.S. history. CVS was a major player in the roll out of the COVID vaccine, when it entered an agreement with the federal government to distribute the shot through its pharmacies.

“Marpai Health is a third-party administrator that currently handles claims for a small percentage of our self-insured members. Dr. David is not employed by Aetna or CVS Health,” a spokesperson for CVS Health told The Daily Beast. “We’re proud to be the leading provider of COVID-19 diagnostic testing and vaccinations, with a focus on underserved communities.”

Mallory Harris, a PhD student at Stanford University, says David is part of a wide network of “perceived experts” who spread COVID-19 misinformation. Harris is working on a long-term study on the topic with the Center for an Informed Public.

Since David has a PhD in computer science from Bar-Ilhan University in Israel, there is nothing to stop him using “Dr.” in front of his name, she says. But it might confuse people who interact with his tweets.

“If people are in an information environment where it becomes more difficult to determine who is an expert,” Harris says. “They could end up interpreting something as medical advice which isn’t medical advice.”

“It’s another example of someone who can masquerade as an expert in vaccines without having credentials in a relevant field,” says Imran Ahmed, the CEO of the Center for Countering Digital Hate, “Algorithms reward only engagement, and there’s nothing that can be guaranteed to infuriate people that someone spouting nonsense and lies about vaccines.”

Ahmed is frustrated that three years into the pandemic, social media platforms have not developed effective ways to curb the spread of COVID misinformation.

“Even more so than extremism, it’s so illustrative of the deficiencies in our information ecosystem,” says Ahmed. He talks about the collective grief sustained by those who lost loved ones to COVID, and what it must feel like to them to see misinformation rewarded with high engagement numbers by platforms like Twitter.

“You are triggering the heartbreak of millions of users in order to generate attention that is then rewarded by platform algorithms. Platforms still haven’t found a way to fix that,” Ahmed says.

David, for his part, continues to tweet unabated. In fact, he believes that it’s COVID skeptics like himself who are the real victims.

“In 399 B.C. Socrates was put on trial and sentenced to death, for the crime of questioning the settled beliefs,” he tweeted on Tuesday. “2422 years later, leading scientists and physicians today are being viciously attacked for questioning the ‘settled science’.”

David did not respond to repeated requests for comment.

Editor’s note: A previous version of this article mistakenly referred to Imran Ahmed as Imran Kahn.