When Marilyn Monroe died in August 1962, with the cause listed as probable suicide, the nation reacted. In the months afterward, there was extensive news coverage, widespread sorrow and a spate of suicides. According to one study, the suicide rate in the United States jumped by 12 percent compared with the same months in the previous year.

Mental illness is not a communicable disease, but there’s a strong body of evidence that suicide is still contagious. Publicity surrounding a suicide has been repeatedly and definitively linked to a subsequent increase in suicide, especially among young people. Analysis suggests that at least 5 percent of youth suicides are influenced by contagion.

People who kill themselves are already vulnerable, but publicity around another suicide appears to make a difference as they are considering their options. The evidence suggests that suicide “outbreaks” and “clusters” are real phenomena; one death can set off others. There’s a particularly strong effect from celebrity suicides.

“Suicide contagion is real, which is why I’m concerned about it,” said Madelyn Gould, a professor of Epidemiology in Psychiatry at Columbia University, who has studied suicide contagion extensively.