Arlington County officials took a step toward reducing homelessness by launching the “100 Homes Arlington” campaign last week, conducting a three-day survey to identify and assess the needs of the area’s homeless.

County officials said the information gathered from the survey will help them serve their most vulnerable residents by moving them as quickly as possible into permanent housing. The survey results were released Friday.

Anita Friedman, a division chief for the county’s Department of Human Services, said the data collected have provided many key details about people who are often overlooked.

“We actually know their name, what they look like and where they sleep,” Friedman said. “It’s no longer a number — it’s a person.”

Twelve survey teams composed of volunteers and county staff went to numerous locations for three days last week from 4 to 7 a.m., contacting almost 190 homeless people.

More than 150 people participated in a survey that asked them about their periods of homelessness, medical conditions, substance abuse and criminal histories.

“We were asking them personal information,” said Kathy Sibert, executive director of Arlington Street People’s Assistance Network, but “it was done in a respectful way.”

The follow-up report revealed that about 70 percent of the those surveyed lived on the street, 24 percent were primarily at a county homeless shelter and the remaining people were staying at a hospital or detention center with nowhere to go upon their release.

Overall, more than a third of survey participants were found to have a variety of “vulnerability factors” that place them at risk of dying if they are not placed in permanent housing quickly. Vulnerability factors are a mixture of conditions that include periods of homelessness longer than six months; a combination of mental health, medical and substance abuse issues; frequent emergency-room visits; and being 60 or older. The average age of those found to be vulnerable was 52, and the average duration of homelessness was seven years.

Sibert said some of the volunteers were prepared for a negative confrontation when awakening people on the street. An unexpected outcome, however, became the norm.

“In fact, [the homeless people] were so touched that someone was taking the time to talk with them,” she said.

According to the report, the county has a higher-than-average percentage of homeless who visit emergency rooms for medical assistance, suffer from liver or kidney diseases and experience weather-related trauma, compared with national data collected by Community Solutions, a nonprofit organization heading the national 100,000 Homes campaign.

The report estimated that the cost of in-patient and emergency-room visits by those surveyed within the past year could reach $3.2 million. About 60 percent of the participants said they had no health insurance.

Friedman said the greatest concern should be for people suffering from mental illness and substance-abuse issues.

“We’ve got more mentally ill on the street," she said. “I’m not sure why.”

More than half of the participants had signs or symptoms of mental illness. About 70 percent had a history of substance abuse. More than 40 percent said they had both.

Friedman and Sibert, however, said the data give the county a chance to provide more efficient service to those homeless residents with the most critical medical and housing needs.

Sibert said community support will determine whether the county’s goal of ending homelessness can be realized.

“Everybody has always talked about ending homelessness. But it seemed so overwhelming,” Sibert said. “Now we’re going into implementation mode. This is a great first step.”