An opioid drug intended to tranquilize large animals has made its way to southeastern Connecticut, according to the latest data on fatal overdoses from the state Office of the Chief Medical Examiner.

The data, released late last week, show that seven of the 1,038 people who died by overdose last year had carfentanil in their systems. Of the seven, two were from southeastern Connecticut.

Carfentanil is an estimated 100 times stronger than fentanyl, which already is up to 50 times stronger than heroin. The tranquilizer first made headlines in summer 2016, when it caused spates of overdoses in states including Ohio, Florida and Kentucky.

According to a review of available records, 2017 marks the first year carfentanil has shown up in Connecticut’s fatal overdose data.

Carfentanil is considered a fentanyl analogue, or drug manufactured to mimic the effects of fentanyl. According to researchers with the National Institute of Standards and Technology, illicit drug makers routinely create new analogues because authorities have to identify and individually ban each one.

Speaking by email, Chief Medical Examiner Dr. James Gill said it can be tough to detect such analogues because there's often just a trace of them mixed in with heroin, fentanyl or another drug. Still, examiners found at least one analogue in 142, or 13.6 percent, of last year's overdose deaths.

“I believe it is new on the drug scene,” Gill said of carfentanil. “Just like the other fentanyl (e.g., acetyl fentanyl) analogues, we did not start seeing them in our toxicology until 2016 and 2017.”[naviga:img hspace="5" vspace="5" border="0" height="321" width="400" align="right" alt="" src="https://www.theday.com/assets/images/ct-overdose-deaths-by-drug-2012-2017.svg"/]

Among the carfentanil-related fatalities last year was a 58-year-old New London man who died after a Sept. 7 overdose in a New London residence. Medical examiners also found diazepam, cocaine, fentanyl, heroin and oxycodone in his system.

Another was a 62-year-old man from Norwich. According to medical examiners, he overdosed Dec. 13 in a Norwich home and later died at the hospital. There were traces of alprazolam, buprenorphine and alcohol in his system.

While the number of overdose deaths increased at a slower rate from 2016 to 2017 than in years past — it jumped 13 percent compared to more than 25 percent in each of the two prior years — an influx of carfentanil could reverse that trend. First responders for months have cautioned that the standard two doses of the overdose-reversal drug naloxone have little to no impact on those who’ve ingested carfentanil.

‘Heartbroken’: High number of fatal overdoses in Norwich

Among other things, the OCME data track where a person was from, where the person overdosed and where the person died. Because towns with hospitals could see higher numbers in the latter category, The Day chose to analyze where people overdosed.

With 32 fatal overdoses in 2017, Norwich by far led the region. The next closest total was in New London, where 14 people overdosed.[naviga:img hspace="5" vspace="5" border="0" height="588" width="400" align="right" alt="" src="https://www.theday.com/assets/images/highest-od-death-rates-towns-2017.svg"/]

Predictably, cities such as Hartford and Bridgeport saw higher numbers. But with population taken into consideration, Norwich’s rate of fatal overdoses ranks it No. 2 among towns that have at least 10,000 residents.

It’s an issue Norwich officials were aware of even before half-year data released in August predicted the city could see 38 overdose deaths in 2017. Since 2016, officials have launched a task force, secured a statewide grant and created a multifaceted awareness campaign to target the problem.

The task force continues to meet almost monthly and has several initiatives in the works, city Human Services Director Lee-Ann Gomes said.

With the help of the city’s Partnership for Success grant, for example, officials are hoping to parse out what is leading so many people to take lethal doses of drugs in Norwich. Gomes said Alderman Sam Browning, who is trained in research methods, has offered to assist.

Gomes said American Ambulance has been developing a tool that would track, in real time, where the city's overdoses are happening. Officials hope to use data from the tool, which should be piloted soon, to inform their prevention efforts.

Gomes also gave a nod to police, who continually confiscate opioids and in February got 650 bags of fentanyl off the streets.

“Again, we are heartbroken at the amount of people who have overdosed and died in Norwich,” Gomes said. “It takes all of us working together and advocating for changes at all levels of government to impact this deadly issue.”

l.boyle@theday.com