In a promotional video made public this week, Ramdev, in his trademark saffron robes and clutching a sample of the medicinal plant produced by Patanjali, the company he co-founded, says: "We've done scientific research and found Ashwagandha ...
doesn't allow blending of corona protein with human protein." He did not provide evidence for the research, which he said had been sent to an unspecified international journal.
There are currently no vaccines or drugs approved to treat or prevent COVID-19, only investigational COVID-19 vaccines and treatments under development.
"These kinds of messages give a false sense of security.
People who are not well educated, they are the ones who will get misled," said Dr. Giridhar Babu, a professor of epidemiology at the Public Health Foundation of India, urging the government to ban such advertisements.
Even potentially harmless tweets about immunity risk confusing people, Babu added.
Multiple calls and emails seeking comment from Patanjali and Ramdev went unanswered.
In a series of tweets, Ramdev also urged Indians to take up yoga to boost immunity, using the hashtag #YogaForCorona.
Ayurveda is an ancient system that includes herbal medicines, exercise and dietary guidelines practiced by millions in India.
Patanjali, one of India's most well-known ayurvedic brands, and several other such firms have been touting their products to fight coronavirus in the densely-populated country of 1.3 billion people.
The virus has infected nearly 200,000 people worldwide and over 140 in India, where three people have died. The ayurvedic companies' tweets have infuriated healthcare professionals who fear they will hurt the battle to stem the virus.
Local media has reported that Ramdev, a household name in India, has also called on people to use hand sanitizer and keep distance from others - recommendations broadly in line with those of global health experts.
Hindu nationalist Prime Minister Narendra Modi in 2014 created the Ministry of Ayush to promote and regulate ayurvedic remedies and yoga.
Manoj Nesari, an adviser at the ministry, said the companies' remedies do help boost immunity, but added he was not aware of claims they could help fight coronavirus.
"Coronavirus is a new virus so obviously there's no evidence (on cures). Once we get complaints we will examine them. Right now I cannot comment," said Nesari.