Researchers gathered for a conference on addiction this week received a grim update on the growing spread of street drugs laced with deadly synthetic opioids including fentanyl.

The trend contributed to a stark rise in overdoses that left more than 90,000 Americans dead during the 12-month period ending in September 2020, according to the latest data.

"We've seen a very significant rise in mortality," said Dr. Nora Volkow, head of the National Institute of Drug Abuse, who spoke Thursday as part of an on-line gathering of the American Society of Addiction Medicine.

Volkow said people are often consuming fentanyl "unbeknownst to them," resulting in a spike in overdose deaths.

According to preliminary figures released earlier this month by the Centers for Disease Control and Prevention, synthetic opioid fatalities rose by an unprecedented 55% during the twelve months ending in September 2020.

(The CDC says overdose death data is reported after a roughly six-month lag because of the challenges of collecting accurate information from jurisdictions around the country.)

Deaths from methamphetamines and other stimulants also surged by roughly 46%, an increase Volkow said is linked to fentanyl contamination.

"It's rare to find people who only overdose on cocaine or who only overdose on methamphetamines," she said. "Fentanyl is being used to lace the illicit drug market because it's very profitable."

In all more than 90,000 Americans died from overdoses in the latest 12-month period for which preliminary data is available. That compares to roughly 70,000 drug deaths during the same period a year earlier.

As the CDC has updated its fatal overdose estimates during the pandemic, the upward trend has shown no sign of slowing. As recently as October, data suggested the country was on track for at least 75,000 overdose deaths in 2o2o.

That would have been a grim new record, but the latest figures make it clear the toll will be far higher. Preliminary data for the full year won't be available until mid-summer.

Studies have also shown a significant increase in the number of Americans using alcohol or drugs to cope with the pressures of the pandemic.

One team of CDC researchers found roughly 13% of people surveyed either began using drugs during the pandemic or increased their use of illicit substances.

On the other hand, drug use increases people's risks from the pandemic. Volkow told the virtual gathering that people with substance use disorders are also at much higher risk of contracting COVID-19 and frequently face more severe outcomes, including death.

In part, those outcomes reflect the fact that people struggling with addiction tend to be less healthy overall. But stigma, fear and lack of access to affordable care are also factors, according to Volkow.

People who use drugs are reluctant to seek medical care even after they contract the coronavirus, she said. When they do ask for help, they often receive inferior care from emergency departments.

"COVID-19 has made us aware how negative the stigmatization of substance use disorders has been over time," Volkow said.

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