Japan plans to trial HIV medications to treat patients infected with coronavirus as the growing number of cases poses an increasing threat to the country’s economy as well as public health.

Yoshihide Suga, the government’s top spokesman, said at a briefing on Tuesday that the government is “currently conducting preparations so that clinical trials using HIV medication on the novel coronavirus can start as soon as possible.”

Suga said he couldn’t comment on how long it would take for the new drug to be approved.

The total number of confirmed infections in Japan stood at 520 as of Monday, including 454 cases from the Diamond Princess cruise ship quarantined off Yokohama port, according to Japan’s health ministry. One person has died from the virus so far.

With Japan’s economy contracting, raising the risk of a recession, the spread of the coronavirus has prompted Tokyo to put limits on public crowds while some companies have begun to urge employees to work from home.

Tokyo’s HIV treatment trials come as those drugs have been touted as a potential cure for the coronavirus around the world. With no therapy proven 100% effective against the virus so far, close to 1,900 people have died in the epidemic in mainland China.

People in China have begun exploring unorthodox ways to obtain treatments, with some appealing to HIV patients and unauthorized importers for medicine.

In Thailand, meanwhile, doctors said they appeared to have had some success in treating severe cases of the coronavirus with a combination of medications for flu and HIV.

DIAMOND PRINCESS EVACUATIONS

Meanwhile more than 300 Americans who had been on the Diamond Princess cruise ship returned home via U.S. government evacuation flights on Monday.

The ship has been under quarantine since early this month, leaving more than 3,000 passengers and crew in confinement, after a passenger who had left the ship in Hong Kong was then diagnosed with the coronavirus.

Around half of the passengers aboard the Diamond Princess are Japanese with the rest foreign nationals, many of whom have expressed frustration over the quarantine.

Foreign governments including Canada, Australia, Italy and South Korea are now also planning evacuations for their citizens on the cruise liner.

A plane chartered by the Canadian government has left for Japan to evacuate its nationals, TV Asahi reported. Canada has said returnees from the cruise ship will undergo another 14-day of quarantine on its soil.

South Korea is also sending a government charter flight on Tuesday to take its four citizens and one Japanese spouse off the boat and bring them to Korea. They have no symptoms, South Korean health minister Kim Kang-lip told a briefing.

Japanese passengers who test negative will begin disembarking as early as Wednesday, the original deadline for the end of ship’s quarantine, Japanese health minister Katsunobu Kato said.

“Everyone wants to return home as soon as possible, so considering that feeling, we are making preparations smoothly, so that they can go back to their home,” Kato told reporters.