Influence of salt and temperature in the growth of pathogenic free-living amoebae

Front Microbiol. 2024 Feb 15:15:1356452. doi: 10.3389/fmicb.2024.1356452. eCollection 2024.

Abstract

Introduction: Free-living amoebae are an extensive group of protistans that can be found in a wide variety of environments. Among them, the Acanthamoeba genus and Naegleria fowleri stand out as two of the most pathogenic amoebae and with a higher number of reported cases. N. fowleri is mainly found in warm freshwater water bodies whereas amoebae of the Acanthamoeba genus are broadly distributed through natural and anthropogenic environments. In this regard, the management and the control of the amoebic populations in swimming pools has become a major public health challenge for institutions.

Methods: The aim of this work was to evaluate the growth pattern of trophozoites of A. griffini and N. fowleri at different temperatures and salt concentrations.

Results and discussion: Our results showed that A. griffini resisted a higher concentration of salt than N. fowleri. Moreover, no trophozoites could withstand the salt levels of the sea in in vitro conditions. This work supports the contention that salinity could represent an important and useful tool for the control of the most pathogenic amoebic populations in recreational water bodies.

Keywords: Acanthamoeba; FLA; NaCl-tolerance; Naegleria fowleri; temperature.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. The present study was supported by the Consorcio Centro de Investigación Biomédica (CIBER) de Enfermedades Infecciosas (CIBERINFEC); Instituto de Salud Carlos III, 28006 Madrid, Spain (CB21/13/00100); and Cabildo Insular de Tenerife 2023–2028 and Ministerio de Sanidad, Spain. IA-J (TESIS 2020010063) and RR-E (TESIS2020010117) was funded by a grant from the Agencia Canaria de Investigación, Innovación y Sociedad de la Información, co-funded with 85% by Fondo Social Europeo (FSE). Assays were also funded by Instant Sport SL, Wavegarden.