Updated

U.S. health authorities said Thursday that more people than earlier thought received possibly tainted steroid injections and some 14,000 patients could be at risk of contracting meningitis in an unprecedented outbreak of the disease.

The U.S. Centers for Disease Control said the number of people at risk, which is 1,000 higher than earlier estimated, was revised after consulting with health authorities.

The CDC also said a Michigan patient is suffering from a joint infection after receiving treatment.

Fourteen patients have died from meningitis and 170 people have been infected, the CDC said in its latest update on Thursday. The number of infections ballooned by 33 since Wednesday, CDC said.

Florida reported a second death from meningitis, and Indiana reported its first death from the outbreak.

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Meningitis cases have been confirmed in 11 states, but 23 states received shipments.

The widening outbreak has alarmed U.S. health officials and focused attention on regulations of pharmaceutical compounding companies such as the one that produced the drugs, the New England Compounding Center, Inc. in Framingham, Mass.

The Food and Drug Administration said more than 50 vials of steroid treatments from the NECC and other sites have tested positive for fungus that causes meningitis.

Health officials said fungus is difficult to detect. So, if a patient who received the suspect injections develops meningitis, but tests negative for fungus, doctors should still treat the patient for fungal meningitis.

The FDA added the outbreak shows the need for a risk-based scheme for dealing with drug compounding.

A Massachusetts health official said Thursday the NECC appears to have violated state licensing laws to produce drugs.

Massachusetts restricts compounding pharmacies to formulating medications for individual prescriptions. But Massachusetts officials are concerned NECC may have been acting more like a drug manufacturer.

"What they were doing instead is making big batches and selling out of state as a manufacturer would," said Gov. Deval Patrick. "And, it's certainly outside of their state license."

According to the FDA, NECC assured federal authorities that it was producing safe products.

“We are actively engaged with federal and state authorities to determine what led to the distribution of these unsafe drugs," Brad Puffer, a spokesman for Massachusetts Attorney General Martha Coakley's office, told FoxNews.com.  "Once we have identified the conduct and circumstances that led to this tragedy, we will identify any potential legal action.”

Meningitis is an infection of the membranes covering the brain and spinal cord. Patients show a variety of symptoms including severe headaches and fever.

Reuters and Fox News' Jonathan Serrie contributed to this report.