If you've been scrolling through social media lately (that is, if you're a human being with access to the Internet), you've probably witnessed the early stages of a new viral video challenge. If you are curious about why this challenge is so popular, how it got started, who is participating, or about the Safe Hands Challenge, keep reading.

The Safe Hands Challenge (which can be found on social media under the hashtags #SafeHands (open in new tab) and #SafeHandsChallenge (open in new tab)) is a hand washing best practice (open in new tab) A viral challenge focused on public health with the goal of educating people around the world about.

As with past viral video challenges (such as the Ice Bucket Challenge (open in new tab)), participants will be asked to film a specific video, post it on social media, and nominate three other people to join the challenge after them.

The Safe Hands Challenge is the brainchild of public health experts at the World Health Organization (opens in new tab). The United Nations (opens in new tab) released a video on March 13 explaining and kicking off the Challenge.

In the video, WHO Director General (opens in new tab), Dr. Tedros Adhanom Ghebreyesus (opens in new tab), explains the proper techniques in our hands, a crucial and front-line defense against the spread of coronaviruses. [There are several practical measures we can take to protect ourselves against new coronaviruses. One of the most important is regular, safe, and effective hand hygiene using soap and water or alcohol-based hand sanitizers."

If you want to join this viral trend, you don't have to wait for someone to "nominate" you. To participate, shoot a video of yourself demonstrating proper handwashing practices and post it on social media. If you do participate, be sure to follow all the steps outlined in the WHO video and wash your hands completely for 40 seconds as recommended.

The WHO hand washing procedure is listed for reference, but if you do not understand the procedure, be sure to watch the video for a visual explanation.

On Sunday, Selena Gomez (open in new tab) became the most high-profile celebrity so far to participate in the challenge with a video shared with her 171 million Instagram followers. Nominated by Arianna Huffington, the singer called on Cardi B (opens in new tab), Gigi Hadid (opens in new tab), and Olivia Wilde (opens in new tab) to join the Safe Hands Challenge next.

Wilde quickly rose to the challenge, posting her own Safe Hands Challenge video and nominating Margaret Queally, Florence Pugh, and Dakota Johnson (opens in new tab).

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