The virus, spread by contact with bodily fluids, has killed than 560 people in Sierra Leone and more than 2,600 in West Africa since the outbreak began last December, according to the World Health Organization. It is killing about half of the people it infects.
Among the volunteers was Idrissa Kargbo, a well-known marathoner who has qualified for races on three continents but whose training and career have been stymied by the outbreak.
Although early responses to the disease have been marred by suspicion of health workers, Freetown residents on Saturday seemed grateful for any information they could get, Kargbo told The Associated Press.
"Some people are still denying, but now when you go to almost any house they say, 'Come inside, come and teach us what we need to do to prevent,'" Kargbo said. "Nobody is annoyed by us."
The strategy has drawn criticism, however. The charity group Doctors Without Borders warned it would be "extremely difficult for health workers to accurately identify cases through door-to-door screening."
Even if suspected cases are identified during the lockdown, the group said Sierra Leone doesn't have enough beds to treat them.
In a district 20 kilometers (12 miles) east of Freetown, police were called in Saturday to help a burial team that came under attack by residents as they were trying to bury the bodies of five Ebola victims, Sgt. Edward Momoh Brima Lahai said.
In northern Sierra Leone, health worker Lamin Unisa Camara said Saturday he had received reports that some residents had run away from their homes to avoid being trapped inside during the lockdown.
"People were running from their houses to the bush. Without wasting time, I informed the chief in charge of the area," said Camara, who was working in the town of Kambia.
Several health care workers and volunteers complained that supply kits were delivered late, preventing their teams from starting on time.
Other Freetown residents, however, were having trouble making it through the three days.
"The fact is that we were not happy with the three days, but the president declared that we must sit home," said Abdul Koroma, the father of nine children in Freetown.
"I want to go and find (something) for my children eat, but I do not have the chance," he said.