PARIS — The name on everybody's masked lips for the past month in France is getting renewed international attention: Professor Didier Raoult received a special guest yesterday at his medical offices in Marseille, as French President Emmanuel Macron visited the controversial microbiologist advocating the use of hydroxychloroquine, a well-known anti-malaria drug, to treat COVID-19.

No press was allowed to attend the surprise presidential visit, and no comment was made afterwards, but Macron's move was quickly criticized as "fueling the hype" surrounding Raoult. It has also prompted comparisons with U.S. President Donald Trump, who has touted hydroxychloroquine as a "game-changer" cure, despite very mixed opinions in the medical community. So who exactly is the colorful infectious disease specialist, and why should we care about him making the rounds? Here are five things to know about Raoult:

• Doctor strange: With his long white hair, goatee, biker-like skull rings, Didier Raoult looks more like General Custer than your typical epidemiologist, daily Ouest France writes. Born in Senegal, the 68-year-old has specialized in the study of obscure diseases throughout a career mired in controversy. The vast number of scientific publications (3,000+) he has co-authored, the investigative website Mediapart points out, has raised eyebrows from his peers, along with his forceful and very public defense of his treatments. Raoult's anti-establishment attitude is no doubt partly responsible for his strong following on Twitter, Facebook, and the 70,000 subscribers to his YouTube channel that boasts 7 million views total — leading public radio station France Inter to call him a bonafide "star du web."

• "Molécule miracle": Despite scant hard evidence that the drug is effective, more than 469,000 people have already signed a petition to make it more widely available. Still, for many in France, the prospect of prescribing a "miracle drug" without due validation protocol from health authorities brings back memories of the Mediator pharmaceutical scandal, after a pill prescribed to overweight diabetics is believed to have killed more than 2,000 people between 1970s-2000s.

• Trial questions: A key criticism leveled at Raoult is that the hydroxychloroquine treatment for coronavirus has not been properly tested. Science magazine writes that "the popular faith" in hydroxychloroquine is only matched by the weakness of the data. Raoult's own "conclusive" studies have either been conducted with very few patients or without control groups, while several other studies have highlighted significant side effects to the use of the antimalarial drug — including heart dysfunctions. Raoult, Science points out, has responded to those criticisms by complaining about the "dictatorship of the methodologists."

• Weirder science: The doctor is also a self-declared climate change skeptic who once told Le Point magazine that "the Earth has generally stopped warming since 1998."

• Conspiracy theories: The hopes raised by Raoult's constant advertising of his treatment have in turn fueled suspicions concerning the pharmaceutical industry, reports Le Monde. "If such a cure exists, why then is it not extended to the whole country — nay, the whole world?"

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