A fungal meningitis outbreak linked to an epidural anesthesia used for cosmetic surgeries in Matamoros is raising questions for the Cameron County Health Authority.

“So what's the cause in this outbreak, it's not clear,” Cameron County Health Authority Dr. James Castillo said, adding that the fungal meningitis is hard to treat. “Why does it only affect two clinics, why is it not as widespread?”

READ ABOUT THE INITIAL OUTBREAK HERE

According to the CDC more than 151 people were under investigation as potential victims who were infected with the fungal meningitis.

Nine of those people died, and four of them were women from the Rio Grande Valley.  

The clinics — River Side Surgical Center and Clinica K3 — were shut down in May when the outbreak was initially reported. Mexico's Ministry of Health is investigating the clinics.

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“So I would imagine that for Mexico they're going to have to figure it out get to the bottom of it,” Castillo said, adding that the investigation could take years.

Castillo compared the Matamoros outbreak to one that happened in the U.S. over a decade ago. That outbreak was connected to a contaminated drug that was being made in a pharmacy.

“Even in the U.S. when we had a similar type of situation it did take a while to get to the bottom of what the cause was and then remedy it,” Castillo said. “And that took years to figure out."

PREVIOUS COVERAGE: Valley man shares wife's battle with fungal meningitis

The CDC is still warning U.S. residents to avoid getting surgery in Mexico because they don't know what happened.

“Until those questions get answered, how are you supposed to prevent them from happening again,” Castillo said.