London — A call for help from the British government has led to 750,000 people to volunteer to assist the country's National Health Service (NHS) as it responds to the coronavirus outbreak. The nationwide volunteer program, slated to go live this week, is meant to help the NHS care for the 1.5 million people with preexisting conditions who are particularly vulnerable to COVID-19. Organizers expected only 250,000 volunteers to sign up; they've been so overwhelmed by the response that they've had to pause applications.

"As history shows, it is often in times of crisis that we pull together and become our best selves," said Catherine Johnstone, chief executive of the Royal Voluntary Service, said in a statement. Royal Voluntary Service is running the program.

"Our team is now working flat out with colleagues in NHS England to process the many thousands of applications we've received, so we can get volunteers up and running as soon as possible and matched with patients that they can begin to support," Johnstone said.

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"Rallying the troops"

The NHS Volunteer Responders will be given four primary tasks: Delivering medicine to vulnerable people who are self-isolating, taking patients to and from doctor's appointments, getting patients home from hospitals, and calling isolated patients to help prevent loneliness.

Doctors, nurses, social workers and pharmacists will be able to call a phone service to get their at-risk patients matched with local volunteers. Charities will also be able to refer people.

"Coronavirus is the biggest challenge we have ever faced, which is why we're rallying the troops and telling the public: Your NHS needs you," said Dr. Nikki Kanani, a family physician and the NHS' Director of Primary Care, in a statement announcing the initiative last week.

"This is one of those once-in-a-lifetime moments where a single action from one person can be the difference between life and death for another," she continued.

Volunteers will have tasks assigned to them via an app, which they can also use to indicate whether they're on or off duty for the volunteer program. The app, run by an organization called GoodSAM, was already operating before the coronavirus crisis to help organize communities around local health issues.

Grassroots response

The NHS Volunteer Responders are not meant to replace the massive network of grassroots groups that have sprung up across the U.K. over the last few weeks. These groups, of which there are about 2,900 across the country, are run entirely by local volunteers.

Organized over messaging apps like Slack, WhatsApp and Zoom, these groups been leafleting neighborhoods to make sure anyone who lacks internet access has the contact details of someone they can reach out to if they need help.

"It's really quite reassuring for people to have a piece of paper. Even though they may not need us now, they may need us in the future," Emma O'Dwyer, a member of one of the local groups in South London, told CBS News.

The local volunteers will continue operating alongside the national program, with much the same motivation.

"Connecting with other people and trying to have some positive influence is good for people. It brings people closer together. It binds people in what is a very very stressful time," O'Dwyer said.