More than 20,000 people applied for a lottery to determine who will receive Montgomery County's remaining 800 doses of flu vaccine, meaning the odds of receiving one are about one in 25.

County officials cut off the flood of applications at 6:30 p.m. Monday after they had received 12,190 applications by phone and 8,440 applications by e-mail, said Mary Anderson, a spokeswoman for the Department of Health and Human Services.

This week, health officials were to begin notifying applicants whether they will receive one of the doses, Anderson said. All who are chosen to receive vaccines should be notified by Monday, she said.

Montgomery officials decided to institute the lottery, in which a computer program randomly selects the 800 "winners," as a way of deciding fairly who among the eligible applicants should receive the limited supply. Like much of the nation, Montgomery received far fewer doses of flu vaccine than normal this year, after half of the nation's expected vaccine supply was thrown out because of possible contamination.

There are doses of flu vaccine in the private sector in Montgomery, but county Health Officer Ulder J. Tillman said "it's hard to get a good handle on" how many doses are with private hospitals and doctors.

"An individual would have to regularly keep checking with their health care provider to get the vaccine," she said.

County health officials hope to receive more doses but will not find out until later this week at the earliest, Tillman said.

Spokesmen for several Montgomery County hospitals declined to say how much vaccine they received but said it was far less than normal.

Robert Jepson, spokesman for Adventist Health Care, which runs Shady Grove Adventist and Washington Adventist hospitals, said the organization received "about a third of what we normally get."

He declined to say how many doses the Adventist hospitals received. He said Adventist regularly runs public flu-shot clinics but had to cancel them this year.

"We're hoping to get an additional supply of vaccines so that we can offer a supply to the community," Jepson said.

Che Parker, spokesman for Suburban Hospital in Bethesda, also declined to say how many doses that hospital received. The hospital will have two flu shot clinics, one Monday and the other Nov. 8. Each clinic will have 100 doses of vaccine available, he said, and both are restricted to younger patients who fall under the Centers for Disease Control and Prevention's guidelines for who should receive a flu shot.

Mike Hall, spokesman for Holy Cross Hospital in Silver Spring, said the hospital received about 650 doses this year, but most will be used to vaccinate doctors, nurses and other employees who regularly come in contact with patients who are at high risk for contracting the flu, he said.

State health officials asked the hospital to give about 65 of its doses to other hospitals in the state, some of which have no flu shots for their own employees, and the hospital plans to do so, Hall said.

"One thing that we need to be assured of is that the front-line caretakers that are going to be seeing people with the flu are going to have the vaccine," he said.

Darlene Harper, infection control nurse at Montgomery General Hospital in Olney, said the hospital has been able to inoculate all of its direct-care employees who wanted a flu shot. Montgomery General Hospital Home Health, which provides home-care nurses to patients, was able to give flu shots to its patients as well, Harper said.

She could not provide specific numbers but said the hospital had enough left over to donate some doses to nursing homes and retirement centers in the county.

Those who receive shots are required to meet the CDC's guidelines for who should receive flu shots. Those guidelines include the following categories: children between 6 and 23 months old; adults older than 65; pregnant women; and people ages 2-64 who have underlying chronic medical conditions such as diabetes, asthma, heart disease and lung disease.

In a normal year, the Montgomery County Health Department administers about 800 flu shots, and that has generally been enough to meet demand because most people go to private health care providers to receive shots, Tillman said. This year, the demand has been far greater because of the shortage.

Health officials have said they fear that with so few people vaccinated, the flu could cause many more illnesses and deaths than it usually does. But until the flu season is in full swing, it will be hard to gauge how the lack of vaccines will affect public health, Tillman said.

"We cannot predict what kind of flu season we are going to have," she said. "What I would really want people to concentrate on is the ways you can prevent getting the flu. They need to really concentrate on cough or sneezing etiquette, on washing hands frequently and concentrating on doing it for more than 20 seconds, trying to avoid others who are coughing and sneezing and, if they become ill, trying to stay home."