PETERBOROUGH, Ont. - Health officials in Peterborough, Ont. have issued a warning that people who use cocaine in the area may be at risk of severe life-threatening infections due to contamination.

The narcotic could be laced with levamisole, an antibiotic used to treat worm infestations in animals.

The warning comes after a local resident using cocaine suffered from a disease in white blood cells that fight infection (called febrile neutropenia / agranulocytosis).

It's not known where the cocaine came from.

Levamisole has been found in cocaine elsewhere in Canada.

At least ten people on Vancouver Island and the lower B.C. mainland have been affected and there have been at least 39 cases in Alberta in the past several months.

Symptoms include high fever, chills, swollen glands, painful sores (oral, anal) and any skin abscess or lung infection that develop more rapidly than usual.