In 2016, a group of national health experts asked the Obama administration to declare a national public health emergency in response to spiking fentanyl deaths, but were ignored, the Washington Post reported Wednesday.

Overdose deaths caused by synthetic opioids, most prominently fentanyl and its analogues, have skyrocketed since 2013. In May of 2016, 11 public health experts wrote a private letter to six Obama administration officials—including the heads of the Office of National Drug Control Policy and Centers for Disease Control—asking for a public health emergency to be declared so that the federal government could better respond to the surge of overdose deaths.

But, in what the Post characterized as "one in a series of missed opportunities," the administration declined to declare an emergency. Instead, fentanyl overdoses continued to grow unabated, with Congress and President Donald Trump not taking action for another two years.

Obama administration officials gave only passing attention to the drug that would come to define 2019's drug crisis. Attorney General Loretta Lynch gave it a passing reference in a 2015 speech; and Tom Frieden, administrator of the CDC, alerted administration officials to the growth in synthetic overdose deaths. But, Frieden told the Post, he often felt like he was not being heard.

"I felt like I was a bit of a voice in the wilderness," Frieden said. "I didn't have the sense that people got this as a really serious problem."

The lack of attention to fentanyl continued through 2016, when after Sen. Ed Markey (D., Mass.) discussed the issue with President Barack Obama en route to an Atlanta appearance, the latter only obliquely referenced the synthetic opioid in a speech. A month later, with the crisis still mounting, the 11 health experts sent their letter.

In it, they told the administration that the crisis appeared "to be intensifying after two years," and called for several policy steps to be taken immediately, including the announcement of a public health crisis.

"A great deal would have been done by the White House simply saying we have this horrible danger out there," John Walters, the Bush administration head of the ONDCP, told the Post. "We saw more action by the White House over an outbreak of tainted food, giving out news releases telling people what to look for, telling people to protect their friends and family, than you did for fentanyl. It's a little ridiculous that we don't use the bully pulpit to at least provide a national warning."

A few months later, the White House would declare a national health emergency, requesting $1.9 billion to fight the Zika virus. Two Americans would ultimately die from Zika; more than 19,000 would overdose on fentanyl in the same year.