An outbreak of fungal meningitis in the United States (US) has been linked to steroid shots for back pain.  The medication, made by a speciality pharmacy in Massachusetts, has been recalled.

The latest numbers from the US Centre for Disease Control and Prevention shows 284 confirmed cases and 23 deaths.

Cases have been reported in 16 states, including Florida, Maryland, New Jersey and New York.

Among the victims is Vilinda York who lies in her Florida hospital bed facing a dry-erase board that lists in green marker her name, her four doctors and a smiley face.

Also on the board is this: 'Anticipated date of discharge: NOT YET DETERMINED'.

The 64-year-old contracted fungal meningitis after receiving three tainted steroid shots in her back.

Like many trying to recover, York, who has been hospitalised since September 27, faces a long and uncertain road.

Many people have died days or even weeks after being hospitalised.

POWERFUL DRUGS

Fungal meningitis - which is not contagious - is a tenacious disease that can be treated only with powerful drugs.

"I'm determined I'm going to fight this thing," she said. "The devil is not going to win."

Dr William Schaffner, an infectious disease specialist who chairs Vanderbilt University's Department of Preventive Medicine, said the treatment includes intravenous anti-fungal medicines that are tricky to use.

"These are powerful drugs. They're toxic," he said.

"You're walking a tightrope because you want to get enough into a patient to have the therapeutic effect while at the same time you're trying not to affect, or to minimise the effect on the liver and kidneys."

Even after leaving the hospital, he said, patients will continue antifungal drugs for weeks or months.