WASHINGTON • Of the 2,900 babies born last year in Cabell county, West Virginia, 500 had to be weaned off opioid dependence.

In Ohio, counties are renting refrigerated trailers to store the mounting number of bodies of drug overdose victims.

In New Hampshire, hospitals have so many overdose patients, they have to treat them in operating rooms and neonatal nurseries.

In Palm Beach county, Florida, where United States President Donald Trump spends his weekends, 10 people died of an overdose last Friday alone - probably from a batch of heroin tainted by fentanyl, a synthetic opioid pain medication.

After a decade and hundreds of thousands of deaths, the US opioid addiction crisis is entering a new phase. With the government finally cracking down on the free flow of prescription painkillers fuelling the crisis, addicts are turning to heroin pouring in from Mexico.

And towns, cities and states are being overwhelmed.

More than 33,000 people across the US died in 2015 from opioid overdoses, up 15.5 per cent from 2014. That equated to a record 10 overdose deaths for every 100,000 people - 10 times the level in 1971, when the government declared its war on drugs after a surge in overdoses.

Yet, six years ago, four in five overdose deaths came from prescription painkillers such as oxycodone and hydrocodone. Now, heroin and heroin-fentanyl deaths account for about half.

In Cabell county, the overdose death rate was about 30 per 100,000.

Lawyer Paul Farrell last week filed a legal suit for Cabell and a neighbouring county, Kanawha, seeking damages from drug companies for dumping massive amounts of addictive opioids into the state, fuelling the addiction epidemic.

"My community is dying on a daily basis," said Mr Farrell.

Every sixth baby born locally suffers from neonatal abstinence syndrome, in which a mother's addiction is passed on to her child.

"The hospital has to rock these babies 24 hours a day as they scream their way through addiction," said Mr Farrell.

"What we're asking for is not only to hold (the firms) responsible for blatantly violating federal and state laws, but also to fix the damage they caused, so that we stop creating another generation of addicts," he said.

How prescription opioid producers and distributors fed the crisis is made clear by previously unreleased US Drug Enforcement Agency (DEA) data reported in December by the Charleston (West Virginia) Gazette-Mail.

It showed that, from 2007 to 2012, the companies sold 780 million opioid painkillers in West Virginia, or 421 extremely addictive pills for every man, woman and child in the poor eastern state.

Every state is feeling the impact. On March 1, Maryland Governor Larry Hogan declared the addiction crisis a "state of emergency", which allowed him to draw on funds normally appropriated for natural disasters to deal with the problem.

Two weeks ago, New York City Mayor Bill de Blasio announced a sweeping new campaign to cut addiction, after the city's overdose death toll hit 1,075 last year.

"The pharmaceutical industry for years has encouraged the overuse of addictive painkillers," said Mr de Blasio.

The surge in deaths follows a shift in the nature of the crisis. After the DEA last year ordered a 25 per cent cutback in the distribution of prescription opioids, addicts turned to heroin. But that drug is frequently cut with fentanyl, which has caused even more overdoses.

"Everybody is starting to see a slowdown of prescription opiates. As you see supply drop, what we are seeing is an equal rise in heroin," said Mr Farrell.

"We are going to see an all-time-high transition to heroin abuse in the next five years."

To raise funds to deal with the issue, cities and counties are suing manufacturers such as Purdue Pharma, which makes OxyContin, the most prevalent of the opioid painkillers; mega-drug wholesalers McKesson, Cardinal Health and AmerisourceBergen; and pharmacy operators such as Rite Aid and Walmart.

AGENCE FRANCE-PRESSE