Update on the Outbreak of Fungal Meningitis in Mexico

By Kiran Thakur, MD FAAN

An Update on the Outbreak of Fungal Meningitis in Individuals Who Underwent Surgical Procedures under Epidural Anesthesia in  Mexico

On May 8th, 2023, public health agencies in the United States (US) were notified through the Emerging Infection Network of the Infectious Disease Society of America of two people hospitalized in Texas with meningitis after receiving surgical procedures in Mexico (1). Three days later, the US CDC notified the Mexico General Directorate of Epidemiology of five cases with meningitis in the United States. All five cases were females with a history of undergoing surgical procedures performed under spinal anesthesia in Mexico (1).  The surgeries were performed in Tamaulipas state, on the border with the US (2). As of June 29th, there are 161 individuals under investigation, 15 suspected cases, 10 probable cases, 9 confirmed cases and 7 deaths reported in the US as well as reported cases in Mexico (3).

Laboratory results from samples collected from patients in the USA and Mexico were consistent with meningitis caused by fungi Fusarium solani, a common soil fungus and colonist of plant materials (3).  Elevated levels of beta-D-glucan, a fungal cell wall biomarker, have been detected in the CSF in several patients. Current US CDC recommendations recommend that all individuals who underwent a medical/surgical procedure in  Mexico, after January 1, 2023, should receive a magnetic resonance imaging (MRI) and lumbar puncture (LP) unless contraindicated (4). This conservative recommendation in asymptomatic individuals is due to the significant case-fatality rate  of over >40% of central nervous system (CNS) Fusarium infections in another recent healthcare-associated outbreak of fungal meningitis in Durango, Mexico (5-7). Additionally, in 2006, fungi in the genus Fusarium were linked to a US outbreak of fungal keratitis that was associated with a contact lens solution (8). Current treatment recommendations include antifungal treatment with liposomal amphotericin B and voriconazole for at least 3-6 months, as there are cases of recurring symptoms and vasculitis when stopping treatment which have been recently reported (4).

Historically, this outbreak reminds us of the largest healthcare associated fungal meningitis outbreak in the US in 2012-2013, due to contaminated lots of methylprednisolone acetate (MPA), an injectable steroid medication (9). In total, 751 patients were reported with fungal meningitis, and/or spinal or paraspinal infection, and/or peripheral osteoarticular infection, and 64 (8.5%) died (10). The pathogen was identified as Exserohilum rostratum, a brown-black soil organism that previously was a rare cause of human infection.

Healthcare-associated neurological infections remain a major threat to human health. Increasing medical tourism globally, as well as increases in antimicrobial resistance are leading to increased risk for healthcare associated outbreaks of public health significance. The current outbreak in North America is a stark reminder of the significant morbidity and mortality of invasive fungal infections, and the risk that unregulated healthcare settings have to public health.

References

1. https://emergency.cdc.gov/han/2023/han00491.asp ⧉
2. https://www.who.int/emergencies/disease-outbreak-news/item/2023-DON470 ⧉
3. https://www.cdc.gov/hai/outbreaks/meningitis-epidural-anesthesia.html#anchor_1686761372360 ⧉
4. https://funguseducationhub.org/interim-guidance-matamoros-fm-outbreak-5_20_23/ ⧉
5. Pan American Health Organization. Technical Note: Meningitis of unknown origin Mexico. https://www.paho.org/en/documents/technical-note-meningitis-unknown-origin-mexico
 ⧉ .
6. Pulice, C. Death toll from mysterious meningitis outbreak in Mexico at 35. https://www.reuters.com/business/healthcare-pharmaceuticals/death-toll-mysterious-meningitis-outbreak-mexico-35-2023-02-06/
 ⧉ . February 6, 2023.
7. Schwartz S, Kontoyiannis DP, Harrison T, Ruhnke M. Advances in the diagnosis and treatment of fungal infections of the CNS. Lancet Neurol. 2018 Apr;17(4):362-72
8. Chang DC, Grant GB, O'Donnell K, Wannemuehler KA, Noble-Wang J, Rao CY, Jacobson LM, Crowell CS, Sneed RS, Lewis FM, Schaffzin JK, Kainer MA, Genese CA, Alfonso EC, Jones DB, Srinivasan A, Fridkin SK, Park BJ; Fusarium Keratitis Investigation Team. Multistate outbreak of Fusarium keratitis associated with use of a contact lens solution. JAMA. 2006 Aug 23;296(8):953-63. doi: 10.1001/jama.296.8.953. PMID: 16926355
9. https://www.cdc.gov/hai/outbreaks/meningitis.html ⧉
10. Kauffman CA, Malani AN. Fungal Infections Associated with Contaminated Steroid Injections. Microbiol Spectr. 2016 Apr;4(2). doi: 10.1128/microbiolspec.EI10-0005-2015. PMID: 27227303.