Clinicians: For 24/7 diagnostic assistance, specimen collection guidance, shipping instructions, and treatment recommendations, please contact the CDC Emergency Operations Center at 770-488-7100.
Clinicians: CDC now has an investigational drug called miltefosine available for treatment of free-living ameba (FLA) infections caused by Naegleria fowleri, Balamuthia mandrillaris, and Acanthamoeba species. If you have a patient with suspected FLA infection, please contact the CDC Emergency Operations Center at 770-488-7100 to consult with a CDC expert regarding the use of this drug.
Although most cases of primary amebic meningoencephalitis (PAM) caused by Naegleria fowleri infection in the United States have been fatal (122/123 in the U.S., 1), there have been two well-documented survivors in North America: one in California 2, 3 and one in Mexico 4. It has been suggested that the survivor’s strain of Naegleria fowleri was less virulent, which contributed to the patient’s recovery. In laboratory experiments, the California survivor’s strain did not cause damage to cells as rapidly as other strains, suggesting that it is less virulent than strains recovered from other fatal infections 5.
Multiple patients have received treatment similar to the California survivor, including amphotericin B, miconazole/fluconazole/ketoconazole, and/or rifampin but only the patient in Mexico has survived making it difficult to determine the efficacy of the treatment regimen.
The survivors received the following medications:
|U.S. California Survivor 2, 3 (1978)||Mexico Survivor 4 (2003)|
|Amphotericin B||Amphotericin B|
|Miconazole – no longer available in US||Fluconazole|
|Sulfisoxazole (IV) – discontinued after Naegleria diagnosed||Ceftriaxone|
Recently an investigational breast cancer and anti-leishmania drug, miltefosine 6, has shown some promise in combination with some of these other drugs. Miltefosine has shown ameba-killing activity against free-living amebae, including Naegleria fowleri, in the laboratory 7, 8. Miltefosine has also been used to successfully treat patients infected with Balamuthia 9 and disseminated Acanthamoeba infection 10. CDC now has a supply of miltefosine for treatment of Naegleria fowleri infection 11. If you are a clinician and have a patient with suspected Naegleria or other free-living ameba infection, please contact the CDC Emergency Operations Center at 770-488-7100 to consult with a CDC expert regarding the use of this drug.
- Yoder JS, Eddy BA, Visvesvara GS, Capewell L, Beach MJ. The epidemiology of primary amoebic meningoencephalitis in the USA, 1962-2008. Epidemiol Infect. 2010;138:968-75.
- Seidel JS, Harmatz P, Visvesvara GS, Cohen A, Edwards J, Turner J. Successful treatment of primary amebic meningoencephalitis. N Engl J Med. 1982;306:346-8.
- Visvesvara GS, Moura H, Schuster FL. Pathogenic and opportunistic free-living amoebae: Acanthamoeba spp., Balamuthia mandrillaris, Naegleria fowleri, and Sappinia diploidea. FEMS Immunol Med Microbiol. 2007;50:1-26.
- Vargas-Zepeda J, Gomez-Alcala AV, Vasquez-Morales JA, Licea-Amaya L, De Jonckheere JF, Lores-Villa F. Successful treatment of Naegleria PAM using IV amphotericin B, fluconazole, and rifampin. Arch Med Res. 2005;36:83-6.
- John DT, John RA. Cytopathogenicity of Naegleria fowleri in mammalian cell cultures. Parasitol Res. 1989;76:20-5.
- Kaminsky R. Miltefosine Zentaris. Curr Opin Investig Drugs. 2002;3:550-4.
- Schuster FL, Guglielmo BJ, Visvesvara GS. In-vitro activity of miltefosine and voriconazole on clinical isolates of free-living amebas: Balamuthia mandrillaris, Acanthamoeba spp., and Naegleria fowleri. J Eukaryot Microbiol. 2006;53:121-6.
- Kim JH, Jung SY, Lee YJ, Song KJ, Kwon D, Kim K, Park S, Im KI, Shin HJ. Effect of therapeutic chemical agents in vitro and on experimental meningoencephalitis due to Naegleria fowleri. [PDF - 7 pages] Antimicrob Agents Chemother. 2008;52:4010-16.
- Martínez DY, Seas C, Bravo F, Legua P, Ramos C, Cabello AM, Gotuzzo E. Successful treatment of Balamuthia mandrillaris amoebic infection with extensive neurological and cutaneous involvement. Clin Infect Dis. 2010;51:e7-11.
- Aichelburg AC, Walochnik J, Assadian O, Prosch H, Steuer A, Perneczky G, Visvesvara GS, Aspöck H, Vetter N. Successful treatment of disseminated Acanthamoeba sp. infection with miltefosine. [PDF - 4 pages] Emerg Infect Dis. 2008;14:1743-6.
- CDC. Investigational Drug Available Directly from CDC for the Treatment of Infections with Free-Living Amebae. MMWR Morb Mortal Wkly Rep. 2013;62(33):666.