Last week was Vancouver's worst for suspected overdose deaths this year.

Eleven people died.

Already, 206 people have succumbed to drug overdoses. That number was 366 for all of 2017.

"Last week's death count is simply ghastly," said Vancouver Mayor Gregor Robertson. "A poisoned supply of street drugs continues to kill our loved ones and devastate families across our city."

Vancouver Fire and Rescue Services also reported an increase in overdose response calls. They responded to 147 calls last week, which was 24 per cent higher than the weekly average for 2017.

"Lives are on the line. People need access to safe prescription drugs rather than being forced to turn to the deadly drugs from organized crime on our streets," said Robertson.

The death toll came just days after the B.C. Coroners Service reported that overdose deaths declined between April and June in B.C.

“More needs to be done in terms of getting people safe access to drugs. Obviously they need an alternative that’s not going to kill them,” says Overdose Prevention Society founder Sarah Blyth. (Tristan Le Rudulier)

Sarah Blyth, who is running for Vancouver city council, is the founder of the Overdose Prevention Society. She says the overdose numbers are not surprising.

"More needs to be done in terms of getting people safe access to drugs. Obviously, they need an alternative that's not going to kill them," Blyth told On the Coast guest host Angela Sterritt.

Fentanyl and other toxic drug contaminants are flooding into Vancouver, including the Downtown Eastside, Blyth says.

Fentanyl has been detected in 81 per cent of provincial drug overdose deaths in the first six months of 2018, according to the B.C. Coroner Service.

The Overdose Prevention Society is the best it has ever been at responding to overdoses, due in part to training, says Blyth.

"The information and how to deal with it is better. But the drug supply is becoming worse," she said.

Most people are dying from overdoses, because they are using alone, says Blyth.

Blyth suggests that an overdose prevention hotline may help. Those using alone can call someone who would sit on the line, get their address and call an ambulance if they overdose.

"People helping people is the easiest way," said Blyth.

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With files from On the Coast and The Canadian Press