President Rodrigo Duterte said Friday using several drops of rubbing alcohol is enough to keep the hands clean.

"Iyong alcohol mura naman iyan. 'Wag nang marami, isang tulo lang," Duterte said in a press conference about the country's response to the coronavirus pandemic.

(Alcohol is cheap, don't use a lot, just a drop.)

He then grabbed a bottle of alcohol and poured several drops into his hand. "Ganoon lang iyan o: 3 drops," he said, briskly rubbing his palms together.

(That's just how much: 3 drops.)

Hands are "the main pathways of germ transmission" and keeping them clean is "the most important measure to avoid transmission of harmful germs and prevent health care-associated infections," according to a 2009 WHO guide.

If the hands are not visibly soiled, one should rub them with an alcohol-based formula for 20 to 30 seconds, it said.

"Apply a coin-sized amount on your hands. There is no need to use a large amount of the product," the WHO said in a separate guide for preventing the spread of COVID-19, last updated on April 29.

One should use sanitizers that contain at least 60 percent alcohol, put enough product on hands to "cover all surfaces", and rub hands together until they feel dry, according to a separate guide by the US Centers for Disease Control and Prevention.