Long-term care facilities need to accelerate their flu vaccination efforts, which lag behind other types of health care facilities, according to federal officials.

An encouraging 77 percent of health care workers, medical and nonmedical, reported getting vaccinated for the flu, and, in the hospital setting, the rate rose to 90 percent, said Tom Frieden, M.D., director of the Centers for Disease Control and Prevention at a news conference. Roughly 47 percent of the U.S. population older than 6 months received a flu vaccination last season.

Speaking at an event today sponsored by the National Foundation for Infectious Diseases, Frieden said that a key area of needed improvement for health care personnel is in long-term care facilities, where only 64 percent of workers reported having been vaccinated. That statistic is especially concerning because the nursing home setting is where health workers come into contact with the most vulnerable population, the elderly, Frieden said.

This season, 171 million doses of influenza vaccine have been manufactured and 40 million doses already have been delivered in the United States, according to data from the CDC.

With vaccination in the news as a result of the GOP debate on Wednesday, health care professionals at the press conference rejected an assertion made by Donald Trump that vaccination plays a role in the incidence of autism among children. Trump also said that spacing out the schedule of vaccines for children could make a difference in autism rates.

“There is no ‘alternative’ immunization schedule,” said Wendy Sue Swanson, M.D., pediatrician, executive director of digital health at Seattle Children's Hospital and a blogger known as Seattle Mama Doc. “Delaying vaccines only leaves a child at risk of disease for a longer period of time; it does not make vaccinating safer,” Swanson said.