How do 14,000 people in 23 states hobble into a doctor's office complaining of back or joint pain -- only to discover, days to months later, that they may have been injected with a potentially lethal infection?

That's the central question for public health authorities who are trying to contain the current multistate outbreak of fungal meningitis linked to contaminated steroid injections.

As of last Thursday, the number of people known to have developed the meningitis had risen to 170, including 14 deaths. Regrettably, those tallies are expected to rise as doctors and patients become increasingly aware of this unusual fungal infection which can take weeks to months to diagnose.

A tip of the hat to public health officials who acted quickly to trace the source of the fungus to contaminated vials of preservative-free "methylprednisolone" -- an anti-inflammatory steroid.

Methylprednisolone is often included in "the shot" given to people with intractable back or joint pain. When injected into the back or neck, the shot is technically considered an "epidural injection" because it deposits steroid into the space between the bony spinal canal and the dura -- the outermost layer of the meninges that covers the brain and spinal cord.

It's hoped that the steroid will relieve pain by exerting potent anti-inflammatory effects directly on irritated nerves or bulging discs.

Health officials subsequently tracked the production site of the tainted methylprednisolone to a specialty pharmacy in Framingham, Mass.: the New England Compounding Center (NECC). By then, NECC had distributed over 17,600 vials of the steroid to 76 facilities across the country.

All those vials would have to be recalled, and thousands of people who had received injections would need to be notified.

News of the meningitis outbreak is raising public concern about the regulatory oversight of "compounding pharmacies" like NECC. It is also highlighting our nation's ongoing problem with critical drug shortages -- and our increasing default reliance on compounding pharmacies to produce the drugs which bona-fide drug manufacturers have abandoned.

Indeed, some critics charge that compounding pharmacies too often operate as actual drug manufacturers. The distinction is important because, unlike pharmacies that are largely regulated by the states, drug manufacturers are subject to strict federal regulations and safety inspections.

But where is that bright line that separates the "compounding" of various ingredients to create a product like methylprednisolone, from the actual "manufacture" of methylprednisolone? And would we actually have avoided the meningitis outbreak if NECC had been subject to federal oversight?

Critics additionally wonder how NECC could have been operating legitimately as a pharmacy. That's because regulatory norms require that pharmacies compound medications only in response to a specific prescription -- written by one doctor for an individual patient. Given NECC's voluminous output of methylprednisolone, it's hard to fathom how vats were not employed for mass production of subsequently allotted vials.

To better understand these issues, I contacted Dr. Marcus Ferrone who is an associate professor of clinical pharmacy at the University of California, San Francisco. He also serves as the director of the Drug Products Services Laboratory, which compounds sterile products for individual patients, clinical applications, research studies and veterinary medicine at the university.

Ferrone explained that drug compounding is a safe and venerable practice -- when it is practiced safely. At UCSF, compounding is done as a prescription-driven process, one doctor's prescription for one patient at a time. And if the compounding involves a preservative-free product like methylprednisolone, which might be injected into the spinal canal, "we put a 24-hour expiration date on it, because we can't guarantee its sterility beyond that time."

Rigorous routine environmental monitoring also ensures that the compounding area itself remains sterile.

It's not yet known whether NECC adhered to these quality standards. But on Wednesday, The Associated Press quoted Massachusetts Gov. Deval Patrick as stating that, rather than dutifully filling individual prescriptions for specific patients under its licensure, NECC "was making big batches and selling them out of a state as a manufacturer would."

Prompted by the current outbreak, various lawmakers are calling for greater federal oversight over compounding pharmacies. But Ferrone hopes those lawmakers will not reactively pull in the federal government to dictate pharmacy practice.

He thinks that more effective regulation can be exerted at state level -- where it ought to remain.

"You know, he said, "this is also not the first time something like this has happened."

He reminded me about the outbreak of bacterial meningitis in our own backyard that was linked in 2001 to a compounding pharmacy in Walnut Creek. Ultimately, three deaths and multiple hospitalizations were attributed to a contaminated compounded steroid. And that incident elevated the issue of greater scrutiny with the state board of California, leading to higher regulatory standards for compounding pharmacies within our state.

Ferrone emphasized that what we most needed all-around was "better education about safe compounding practices -- that's the key."

When asked whether patients should be inquisitive about taking compounded drugs, Ferrone said, "Absolutely. A level of personal responsibility should prompt a patient to ask their doctor where a compounded medication was produced and who prepared it, and whether licensure issues or disciplinary actions attached to the compounding pharmacy. And while an individual doctor may not have that information at hand, he or she should be aware whether the pharmacy they're using reliably investigates those questions."

Kate Scannell is a Bay Area physician and syndicated columnist. She is the author of "Flood Stage" and "Death of the Good Doctor."