The 'We Belong Together' singer and the 'How Do You Sleep' hitmaker were just two of the stars supporting those on the front line as the world fights the virus pandemic.
She wrote: "Sending my insurmountable gratitude to all healthcare workers and first responders around the world. We appreciate you so much!! ... Please show yourself and tweet me so we can all celebrate you! (sic)"
Whilst Sam shared: "Here's to all the healthcare workers ... Make yourself known in the replies, and thank you for all that you do #WorldHealthDay (sic)"
Liam Gallagher, Shakira and Sofia Vergara were also sharing messages.
Liam wrote on social media: "Brothers and Sisters make yourself known if your a health worker? LG x #worldhealthday (sic)"
Whilst the 'Hips Don't Lie' singer shared: "It’s World Health Day, so let’s honor those health care workers on the frontlines who are true heroes. Tell me your story or tag a health care worker you know so we can thank them for all for their bravery and selflessness. (sic)"
Sofia tweeted: "To the amazing doctors, nurses and medical staff who are putting their lives on the line every single day, thank you #ThankYouHealthCareHeroes (sic)"
Antonio Banderas also had a supportive message for health workers.
He wrote: "I join to the world's applause for all the medical staff, who fight for our health. #WorldHealthDay (sic)"
The celebrities were responding to Twitter's official message, which asked people to come together to applaud the frontline workers.
They wrote on their account: "Tweet some Clapping hands sign for all the amazing healthcare workers around the world. #WorldHealthDay (sic)"