When Dian heard that the coronavirus had arrived in Indonesia at the end of March, she stocked her kitchen with ginger, turmeric and lemongrass.

However, the 37-year-old mother of two wasn't using the spices for cooking. Instead, she boiled them down into a traditional herbal drink called "jamu."

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Dian and her family now drink the herbal mixture every day. "Since we regularly drink jamu, my body feels fresher and fitter," Dian, who lives in West Java, told DW.

"I got information about jamu online. I don't believe claims that it can fight COVID-19, but I do believe it naturally improves and regenerates our cells," Dian said, adding she drinks the mixture to boost her immunity.

Dian is not alone. Herbal drinks in Indonesia have surged in popularity during the pandemic, as they are affordable and easy to make at home.

Sido Muncul, a major Indonesian herbal medicine producer, reported a spike in sales in the first half of 2020, driven mainly by vitamin and ginger drinks.

However, as Indonesia experiences a surge in COVID-19 cases, the prevalence of false cures and quick fixes presents a public health problem.

On Thursday, Indonesia recorded a record high 3,622 new COVID-19 infections and 134 fatalities within 24 hours, according to the Indonesian Health Ministry. The total number of cases is now over 184,000, with 7,750 deaths and 132,055 recoveries.

Hoaxes and quack cures

In August, an interview was posted on Indonesian YouTube with Hadi Pranoto, a man claiming to be a microbiology professor touting a COVID-19 cure he concocted from herbs. Pranoto said his herbal drink could cure COVID-19 in three days, and would help the government fight the pandemic.

The interview was conducted by a popular Indonesian YouTuber, Anji, who has over 3.6 million subscribers, according to the Jakarta Post. YouTube since removed the interview, and police are investigating Anji and Pranoto for spreading misinformation.

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Government offices have also been involved in promoting dubious remedies. In July, the Indonesian Ministry of Agriculture promoted an aromatherapy necklace with eucalyptus leaves it labeled as "anti-coronavirus."

Indonesian Minister of Agriculture Syahrul Yasin Limpo claimed that wearing the necklace for 15 minutes could kill 42% of the virus, and 30 minutes would kill 80% of the virus.

The minister's claims drew widespread skepticism from Indonesia's scientific community. The ministry later walked back its claims, saying that the aromatherapy products are only meant to prevent the disease. However, it did not revise the claim on the product's label.

Experts warn that such claims mislead the public into feeling protected, which may lead people to ignore health protocols like social distancing and wearing masks.

Herbal medicine 'no cure'

Yohanes Wibowo, an Indonesian scientist and a PhD candidate at the Department of Experimental Pharmacology at Heidelberg University in Germany, told DW that the ministry's aromatherapy claims have no scientific backing.

"I couldn't find any publication showing the ministry had done vitro tests on a virus culture, let alone clinical trials," Wibowo said, adding that there is no herbal or non-herbal medicine that is proven to be 100% effective against coronavirus.

"There are lists of medicines that are in the process of clinical trials, yet none of them show a result that can be categorized as an anti-coronavirus medicine," he said.

Professor Amin Soebandrio from the Eijkman Institute for Molecular Biology in Jakarta said that herbal medicines are not meant to cure.

"If there is a claim that it can cure a patient with COVID-19, that is definitely not true," he told DW, adding that herbal medicine manufacturers should not make excessive claims about their products.

He also urged the public to be more critical of claims of herbal cures.

"It is better for us to see herbal products as supplements, to improve health and the immune system," he said.

Read more: Germany: Scientists test artemisia plant against coronavirus

Research on herbs and coronavirus

Still, herbal remedies have been part daily life in Indonesia for centuries. Indonesian scientists have been researching COVID-19 treatments using natural ingredients, such as those found in jamu drinks.

One research project is being conducted by a team from the Indonesian Institute of Science (LIPI) and the Association of the Indonesian Doctors for the Development of Traditional and Herbal Medicines.

According to LIPI's website, the team is looking at how two types of herbal medicines modulate the immune system. Ingredients include the fungus Cordyceps militaris, and a combination of ginger and herbal plants.

Clinical trials were completed in August, and the data is being checked for accuracy, before being passed on for approval by Indonesia's Food and Drug Supervisory Agency (BPOM). The LIPI has said it will not make any claims of efficacy until the BPOM issues its findings.

With reporting by Prihardani Ganda Tuah Purba in Jakarta.