Occurrence of Free-living Amoebae in Nasal Swaps of Patients of Intensive Care Unit (ICU) and Critical Care Unit (CCU) and Their Surrounding Environments

  • Maryam NIYYATI Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Alireza NAGHAHI Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Hamed BEHNIAFAR Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
  • Zohreh LASJERDI Dept. of Medical Parasitology and Mycology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Keywords: Immunosuppression, Hospital, Iran


Abstract Background: The presence of potentially pathogenic Free Living Amoebae (FLA) in hospital environment could be a health hazard for high-risk patients such as immunosuppressed patients. This study was carried out to investigate the presence of potentially pathogenic FLAs in the environment and medical instruments of different hospital wards, and nasal swabs of immunosuppressed patients of a hospital in Tehran, Iran. Methods: In this cross-sectional study, 60 environmental (26 samples) and nasal swab (34 samples) samples were collected between Dec 2015 and Feb 2016. The samples were assessed using culturing, staining and morphological methods based on page key. To decrease the bacterial and fungal contamination and better identification of FLAs, cloning was performed. Results: Overall, 17 (28%) samples, including 13 environmental samples and 4 nasal swabs samples, were found positive for FLAs. The most frequent amoebae were Acanthamoeba spp. and two plates had mix contamination of Acanthamoeba spp. and Vahlkampfiids/Vermamoeba. Overall, Acanthamoeba species (58%), Vahlkampfiids (26%) and V. vermiformis (15%) were identified in clinical and environmental samples. Conclusion: The occurrence of these FLAs in environmental and clinical samples of hospital may threat health status of patients directly, particularly in immunosuppressed patients, and can transmit other pathogens. Thus, the increasing awareness of clinical setting staffs about FLAs and improvement of disinfection methods in hospitals is needed.  


Visvesvara GS, Moura H, Schuster FL (2007). Pathogenic and opportunistic free-living amoebae: Acanthamoeba spp., Balamuthia mandrillaris, Naegleria fowleri, and Sappinia diploidea. FEMS Immunol Med Microbiol, 50(1):1-26.

Marciano-Cabral F, Cabral G (2003). Acanthamoeba spp. as agents of disease in humans. Clin Microbiol Rev, 16(2):273-307.

Qvarnstrom Y, da Silva AJ, Schuster FL et al (2009). Molecular confirmation of Sappinia pedata as a causative agent of amoebic encephalitis. J Infect Dis, 199(8):1139-42.

Aitken D, Hay J, Kinnear FB et al (1996). Amebic keratitis in a wearer of disposable contact lenses due to a mixed Vahlkampfia and Hartmannella infection. Ophthalmology, 103(3):485-94.

Niyyati M, Lorenzo-Morales J, Rezaie S et al (2010). First report of a mixed in-fection due to Acanthamoeba geno-type T3 and Vahlkampfia in a cosmet-ic soft contact lens wearer in Iran. Exp Parasitol, 126(1):89-90.

Lorenzo-Morales J, Martínez-Carretero E, Batista N et al (2007). Early diagnosis of amoebic keratitis due to a mixed infection with Acanthamoeba and Hartmannella. Parasitol Res, 102(1):167-9.

Visvesvara GS, Sriram R, Qvarnstrom Y et al (2009). Paravahlkampfia francinae n. sp. masquerading as an agent of primary amoebic meningoen-cephalitis. J Eukaryot Microbiol, 56(4):357-66.

Hajialilo E, Behnia M, Tarighi F et al (2016). Isolation and genotyping of Acanthamoeba strains (T4, T9, and T11) from amoebic keratitis patients in Iran. Parasitol Res, 115(8): 3147-51.

Movahedi Z, Shokrollahi MR, Aghaali M, Heydari H (2012). Primary amoebic meningoencephalitis in an Iranian infant. Case Rep Med, 2012: 782854.

Khan NA (2009). Acanthamoeba: biology and pathogenesis: Caister Academic Press, Norfolk, Great Britain.

Walochnik J, Scheikl U, Haller‐Schober EM (2015). Twenty years of Acanthamoeba diagnostics in Austria. J Eukaryot Microbiol, 62(1):3-11.

Winiecka-Krusnell J, Linder E (2001). Bacterial infections of free-living amoebae. Res Microbiol, 152(7):613-9.

Thomas V, Bouchez T, Nicolas V et al (2004). Amoebae in domestic water systems: resistance to disinfection treatments and implication in Legionella persistence. J Appl Microbiol, 97(5):950-63.

Lasjerdi Z, Niyyati M, Haghighi A et al (2011). Potentially pathogenic free-living amoebae isolated from hospital wards with immunodeficient patients in Tehran, Iran. Parasitol Res, 109(3):575-80.

Memari F, Niyyati M, Haghighi A et al (2015). Occurrence of pathogenic Acanthamoeba genotypes in nasal swabs of cancer patients in Iran. Parasitol Res, 114(5):1907-12.

Trabelsi H, Dendana F, Neji S et al (2016). Morphological and molecular identification of free living amoeba isolated from hospital water in Tunisia. Parasitol Res, 115(1):431-5.

Rezaeian M, Niyyati M, Farnia S, Haghi AM (2008). Isolation of Acanthamoeba spp. from different environmental sources. Iran J Parasitol, 3(1):44-7.

Khan NA (2006). Acanthamoeba: biology and increasing importance in human health. FEMS Microbiol Rev, 30(4):564-95.

Schroeder JM, Booton GC, Hay J (2001). Use of subgenic 18S ribosomal DNA PCR and sequencing for genus and genotype identification of acanthamoebae from humans with keratitis and from sewage sludge. J Clin Microbiol, 39(5):1903-11.

Behniafar H, Niyyati M, Lasjerdi Z, Dodangeh S (2015). High occurrence of potentially pathogenic free living amoebae in water bodies of kaleybar and khodaafarin, east azerbaijan province. Curr World Environ, 10(Special Issue 1):727-31.

Niyyati M, Lasjerdi Z, Zarein-Dolab S et al (2015). Morphological and Molecu-lar Survey of Naegleria spp. in Water Bodies Used for Recreational Purpos-es in Rasht city, Northern Iran. Iran J Parasitol, 10(4):523-9.

Niyyati M, Karamati SA, Morales JL, Lasjerdi Z (2016). Isolation of Balamuthia mandrillaris from soil samples in North-Western Iran. Parasitol res, 115(2):541-5.

Rezeaian M, Farnia S, Niyyati M, Rahimi F (2007). Amoebic keratitis in Iran (1997-2007). Iran J Parasitol, 2(3):1-6.

Lasjerdi Z, Niyyati M, Lorenzo-Morales J et al (2015). Ophthalmology hospital wards contamination to pathogenic free living Amoebae in Iran. Acta Parasitol, 60(3):417-22.

Rohr U, Weber S, Michel R et al (1998). Comparison of free-living amoebae in hot water systems of hospitals with isolates from moist sanitary areas by identifying genera and determining temperature tolerance. Appl Environ Microbiol, 64(5):1822-4.

Thomas V, Herrera-Rimann K, Blanc DS, Greub G (2006). Biodiversity of amoebae and amoeba-resisting bacteria in a hospital water network. Appl Environ Microbiol, 72(4):2428-38.

Muchesa P, Leifels M, Jurzik L et al (2017). Coexistence of free-living amoebae and bacteria in selected South African hospital water distribution systems. Parasitol Res, 116(1):155-165.

Costa AO, Castro EA, Ferreira GA et al (2010). Characterization of acanthamoeba isolates from dust of a public hospital in Curitiba, Parana, Brazil. J Eukaryot Microbiol, 57(1):70-5.

Carlesso AM, Artuso GL, Caumo K, Rott MB (2010). Potentially pathogenic Acanthamoeba isolated from a hospital in Brazil. Curr Microbiol, 60(3):185-90.

Niyyati M, Lorenzo-Morales J, Rahimi F et al (2009). Isolation and genotyping of potentially pathogenic Acan-thamoeba strains from dust sources in Iran. Trans R Soc Trop Med Hyg, 103(4):425-7.

Niyyati M, Lorenzo-Morales J, Rezaeian M et al (2009). Isolation of Balamuthia mandrillaris from urban dust, free of known infectious involvement. Parasitol Res, 106(1):279-81.

Teixeira LH, Rocha S, Pinto RMF et al (2009). Prevalence of potentially pathogenic free-living amoebae from Acanthamoeba and Naegleria genera in non-hospital, public, internal environments from the city of Santos, Brazil. Braz J Infect Dis, 13(6):395-7.

Chan L-L, Mak J-W, Low Y-T et al (2011). Isolation and characterization of Acanthamoeba spp. from air-conditioners in Kuala Lumpur, Malaysia. Acta Trop, 117(1):23-30.

Cabello-Vílchez AM, Martín-Navarro CM, López-Arencibia A et al (2014). Genotyping of potentially pathogenic Acanthamoeba strains isolated from nasal swabs of healthy individuals in Peru. Acta Trop, 130:7-10.

How to Cite
NIYYATI M, NAGHAHI A, BEHNIAFAR H, LASJERDI Z. Occurrence of Free-living Amoebae in Nasal Swaps of Patients of Intensive Care Unit (ICU) and Critical Care Unit (CCU) and Their Surrounding Environments. Iran J Public Health. 47(6):908-13.
Original Article(s)