(CNN) The national blood supply is low, empty shelves signal foreboding at food banks and vulnerable communities are at risk.

As coronavirus spreads across the US, people are worried about keeping their families safe. But, what about your fellow man? For people in need, dealing with coronavirus is an added stress.

The organizations that support them are asking for help in this time of uncertainty. Some are facing serious challenges as the virus spreads , while others are coming up with creative ways to anticipate their needs.

This is how you can help.

Interactive: A guide to helping and getting help during the coronavirus crisis

There is a serious need for blood

Blood drives are being canceled and the American Red Cross is asking people to donate.

More than 600 blood drives across the country have been canceled due to coronavirus concerns, the American Red Cross said Friday. That's about 18,000 blood donations that were never made.

"In my 31 years, I've not been as concerned about what could happen to the blood supply as I am now simply because of the degree of influence the coronavirus is having over public decisions," Chris Hrouda, president of Red Cross Blood biomedical services, told CNN.

It's important that people donate now while parts of the country are still healthy, Hrouda said. About 80% of Red Cross blood collections come from blood drives hosted by sponsors like schools, churches and businesses.

Blood supplies must constantly be replenished because blood is perishable. When blood drives are canceled, that threatens the inventory, he said. A unit of red blood cells can last for 42 days, while platelets only have a five-day shelf life.

How you can help: Blood donors are needed, as are sponsors to host drives. All types are needed, but blood type O and platelets are what's most needed, said the Blood donors are needed, as are sponsors to host drives. All types are needed, but blood type O and platelets are what's most needed, said the American Red Cross . You can find a blood drive near you through the American Red Cross here or America's Blood Centers here

The shelves at some food banks are going unstocked

Lone boxes of pasta sit on the shelves at the Food Bank of Lower Fairfield County in Connecticut.

Canned food donations are declining and one food bank in Stamford, Connecticut, can't keep its shelves stocked.

Food Bank of Lower Fairfield County. Unfortunately, people seem to be stockpiling canned goods at home, said Kate Lombardo with the

"There's another population that needs to be able to hunker down for the possibility in case they are quarantined," Lombardo told CNN. "Most people don't have that extra $100 to $200 to spend on food to ready their household for two weeks' worth of groceries."

Pasta, spaghetti sauce and cereal are usually always on the shelves, but these days, even those items are gone, she said. The food bank has had to use donations to purchase food to replenish their supply.

"It's just frightening for people who live hand to mouth on a daily basis," Lombardo said. "There's already a stress factor of poverty, let alone the additional stress coming from a pandemic."

The food bank provides food to 90 agencies and programs, like food pantries and soup kitchens, which give the food to those in need.

Soup kitchens are feeling the ripple effect, too. Brooklyn soup kitchen and women's shelter Community Help in Park Slope, Inc. says it will not close, despite the uptick in coronavirus cases in New York.

The soup kitchen has moved from serving indoor seated meals to take-out, so there aren't large gatherings of people, said Executive Director Denise Scaravella.

"We're not turning anybody away. We have donations for cold lunch supplies," Scaravella told CNN. "Volunteers are showing up, we are cooking and we are handing the food out. We just aren't having people to come in and eat."

Some homeless shelters are ready if the virus hits a susceptible population

Volunteers at Central Union Mission men's homeless shelter disinfect surfaces in Washington DC.

There haven't been reported cases of coronavirus in the homeless population that we know of, but there's a fear of it hitting this already vulnerable group.

The suggestions to wash your hands and self-quarantine aren't a feasible option for the homeless, said Giselle Routhier, policy director at Coalition for the Homeless in New York.

"The recommendation to self-quarantine is impossible for homeless New Yorkers," Routhier said. "That is why it is crucial that New York ensures that everyone has a real home."

The Union Rescue Mission is a shelter on Skid Row in Los Angeles. It's taken aggressive measures to make sure the people it serves stay safe.

The shelter moved bunk beds to make sure they are six feet apart and it's already set up a quarantine area for anyone exhibiting symptoms.

"We've set up a family quarantine in a family wing and have two families exhibiting likely flu symptoms, but since we can't test and hospitals did not test, we can't confirm any cases yet," said shelter CEO Rev. Andy Bales. "We are erring in the side of caution."

The shelter added several stations so people can wash their hands with hot water and follow good hygiene, he said. Door knobs, door handles and elevator buttons are being disinfected 9 times per day.

How you can help: Homeless shelters like Union Rescue Mission are asking that people share essentials like toilet paper, soaps, hand sanitizer and disinfectant wipes. Masks, gloves and protective equipment are also welcome, as staff at shelters need to be able to protect themselves while serving those in need.

To report a person who needs help on the street, you can call 311 to connect with homeless outreach in your city, or dial 211 to reach local, essential community services. The Veterans Administration also operates a 24/7 hotline for homeless vets at 877-4AID-VET (877-424-3838) and an online chat service.

Homebound elderly need meals

Volunteers at Meals on Wheels deliver food to a man in Portland.



While the public worries about working from home and isolating, a huge segment of the population already does that: the elderly.

Often elderly people may have trouble shopping and cooking if they have mobility issues.

Meals on Wheels programs provide hot meals daily to seniors and those who are homebound. Getting a hot meal is important for nutrition, but it's also a chance for a senior to have a visit and not feel so isolated, said Steve King with Meals on Wheels of Tampa

"We're preparing frozen meals that in the event that we run too short and can't get a hot meal to somebody every day, we can give them frozen meals for a seven-day period," King said.

"Delivery methods are also being adjusted to lessen the risk of person to person contact," said Meals on Wheels America spokeswoman Jenny Young. "Volunteers may no longer enter the home and they may deliver more shelf-stable or frozen meals at one time to lessen the frequency of delivery."

Losing that personal connection will be tough, so the organization said many local programs will call its seniors to check on their safety and wellbeing, she said.