In the corner of a D.C. home sit four stacks of handwritten cards.

Count them and you’ll find there are more than 1,700.

Read them and you’ll see one expression of gratitude after another.

When the going got tough you pulled on through and helped others to live.

Thanks for all the ways you are making our city a better place in this time of covid and other sadness and hardship.

Your work is vital and I appreciate it.

On Thursday, those thank-you cards will end up in the hands of doctors, nurses and the many other staff members who work at Howard University Hospital.

Those health-care workers won’t know much about the people who sent them, other than what the details inside each reveal. Some will contain the boxy lettering of children just learning to write. Others will reflect the shaky scrawls of a woman who struggled to hold a pen steady. Some might mention Tokyo. Others might give a nod to neighborhoods in Maryland.

How those cards came to exist — and end up at the hospital — is an incredible story that involves social justice and artistry and people from across the world coming together.

Mostly, though, it involves singing — lots of singing.

Shortly after the coronavirus reached the Washington region, and isolation became a norm for many, D.C. resident Jo Rasi launched a program called the “Daily Antidote of Song.”

The concept was simple: Create an online space for people to come together at the same time each day to sing along with a musical artist.

At the time, the virus was expected to disrupt life for a few months, and Rasi figured, if nothing else, the program would offer people in the Washington region a temporary community. Then three months turned into eight, and eight into 11, and the audience grew into one that includes people from D.C., 46 states and 15 countries.

A 10-year-old girl in Massachusetts now logs on at the same time as her grandparents in Poland.

A woman in Texas comes to sing on the same days as her sister in Vancouver.

The group is filled with people who are young and old, healthy and sick, musically skilled and too shy to sing in public.

The way the program works is that people log on at noon, put their devices on mute and belt out the song picked by the musician that day. That means they can only hear their own voices and that of the artist. It’s an experience one member described with a joke: “What do you call 150 Zoom singers? A duet.”

Rasi, who works for the Washington Revels and Carpe Diem Arts, both of which have long used music to bring people together, says she never expected the Daily Antidote to turn into what it has become.

“We have a community of people who come into this room every day who have never met and who are all developing friendships now,” she says. At a time of division, it feels good to see people from across the country coming together, she says.

After George Floyd’s killing, the group started focusing on social justice, singing about it and talking about it. Rasi thinks about things such as how it’s not enough to describe a place as welcoming — people need to work to make it that way.

“It feels to me for the first time the work that I’m doing isn’t about singing for social change,” she says. “It’s about really creating social change.”

She opens each session by saying the names of everyone logged on and sometimes shares details about the lives of members.

Kathy Maher, of McLean, recalls the day Rasi asked if she could share with the group a bit about her situation. She had been diagnosed with multiple myeloma, a form of cancer, two months before the pandemic began.

“At the beginning, I didn’t even want to tell my son,” Maher, who is 71, says. “After she asked me, I thought, ‘I can’t believe I’m saying yes,’ because I’m a very private person.”

Since then, Maher says, she has received messages weekly from other group members asking how she’s feeling. Just the other day, a woman from England sent her a private note during the singalong asking something toward: “You look tired. Are you ok?”

“I thought, ‘Isn’t this remarkable? It’s just so incredibly kind,’ ” Maher says. She tries to tune in daily, even if means keeping her camera off while at a medical appointment. “You start looking for people on your screen, and if they aren’t there for one day, you start wondering about them.”

When a woman’s mother died of covid-19, the group mourned with her. And when members have experienced birthdays, the group has celebrated with them.

Ana Andura, who lives in Maryland and was a D.C. schoolteacher before retiring last year, say she came to the Daily Antidote shortly after receiving a terminal cancer diagnosis.

“Although I never studied singing or music, I naturally sing. There is some magic in singing, and singing with others, with a purpose,” the 65-year-old says. She recalls one day when a Greek musician performed for the group and she stood up and danced. “It was so therapeutic for me. Singing, yes. But dancing, I’ve been more shy about moving my body, and those people brought me out. I was turning around and around.”

She describes the Daily Antidote as bringing people out of their own suffering and allowing them to join something bigger than themselves.

“I have my ups and downs,” she says. She has received two rounds of chemotherapy and is now going through immunotherapy while participating in the singalongs. “I’m not jumping and dancing every day. But I keep my spirits up saying to myself, ‘I’m not alone. Many people suffer with me. And there must be a purpose to this, even if I don’t understand it completely.’ ”

When Rasi realized the group would approach its 300th song together at the end of this month, she decided to ask everyone to participate in a group project. That resulted in the thank-you cards that now sit in her home.

They have come from Ireland and Idaho and many places in between. At one point, a virtual card-writing event brought together a 101-year-old woman in Michigan, a college student in Blacksburg, Va., and a man in Tokyo.

Andura wrote cards and Maher did, too. At first, Maher was hesitant to participate because a medication she was taking caused her hands to shake five days out of the week. But she says she used the two days they were steadiest to write about 150 cards.

Rasi has spoken to hospital officials about the cards and is coordinating a time to drop them off.Cynthia Livingston, who is the director of community relations at the hospital, says the number of cards that have been collected will cover almost all of the staff.

“Just to think someone sat down, that strangers took the time to thank you for your effort, it means everything in the world,” Livingston says. Right now, because of the uptick in coronavirus cases and the new variations that are appearing, it can feel as if the virus is fighting back just as hard as health-care workers are fighting against it, she says. “Getting something like this lets us know nobody has given up hope on us.”

Livingston says that on the day the cards are handed out, a person will probably stand at one of the doors and give them to staff members as they arrive for a shift or leave after one.

But the story of those cards won’t end with that exchange.

It will end in the only fitting way — with a song.

Photos of some of those workers with their cards will be compiled into a slide show and shared on the Daily Antidote. On that day, vocalists Crys Matthews and Ysaÿe Barnwell, who has a master’s degree in public health from Howard University, will sing original songs titled “Selfless” and “More than a Paycheck.”

And a group of people who have never met but come together daily will put their devices on mute and sing along with them.

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