{"id":983,"date":"2018-08-14T15:23:03","date_gmt":"2018-08-14T15:23:03","guid":{"rendered":"https:\/\/www.ampac1.com\/blog\/differential-development-of-legionella-sub-populations-during-short-and-long-term-starvation\/"},"modified":"2026-04-13T00:00:00","modified_gmt":"2026-04-13T00:00:00","slug":"differential-development-of-legionella-sub-populations-during-short-and-long-term-starvation","status":"publish","type":"post","link":"https:\/\/www.ampac1.com\/blog\/differential-development-of-legionella-sub-populations-during-short-and-long-term-starvation\/","title":{"rendered":"Differential development of Legionella sub-populations during short- and long-term starvation"},"content":{"rendered":"
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Legionella Bacteria Water Systems<\/strong> is a critical aspect of modern water treatment. AMPAC USA provides industry-leading solutions that ensure safe, clean water for residential, commercial, and industrial applications. Our systems are engineered for maximum contaminant removal and long-term reliability.<\/p>\n<\/div>\n

Schrammel, Barbara; Cervero-Arago, Silvia; Dietersdorfer, Elisabeth; Walochnik, Julia; Lueck, Christian; Sommer, Regina; Kirschner, Alexander<\/span><\/p>\n

WATER RESEARCH, 141 417-427; <\/span>10.1016\/j.watres.2018.04.027\u00a0<\/span><\/a>SEP 15 2018<\/span><\/p>\n

Abstract: <\/b>Legionella are among the most important waterborne pathogens in industrialized countries. Monitoring and surveillance of Legionella in engineered water systems is usually performed with culture-based methods. Since the advent of culture-independent techniques, it has become clear that Legionella concentrations are often several orders of magnitude higher than those measured by culture-based techniques and that a variable proportion of these non-culturable cells are viable. In engineered water systems, the formation of these viable but non-culturable (VBNC) cells can be caused by different kinds of stress, such as, and most importantly, nutrient starvation, oxidative stress and heat. In this study, the formation of VBNC cells of six Legionella strains under conditions of starvation was monitored in mono species microcosms for up to one year using a combination of different viability indicators. Depending on the strain, complete loss of culturability was observed from 11 days to 8 weeks. During the starvation process, three distinct phases and different sub-populations of VBNC cells were identified. Until complete loss of culturability, the number of membrane-intact cells decreased rapidly to 5.5-69% of the initial cell concentration. The concentration of the sub-population with low esterase activity dropped to 0.03-55%, and the concentration of the highly esterase-active sub-population dropped to 0.01-1.2% of the initial concentration; these sub-populations remained stable for several weeks to months. Only after approximately 200 days of starvation, the number of VBNC cells started to decrease below detection limits. The most abundant VBNC sub-populations were characterized by partially damaged membranes and low esterase-activity. With this study, we showed that upon starvation, a stable VBNC Legionella community may be present over several months in a strain-dependent manner even under harsh conditions. Even after one year of starvation, a small proportion of L pneumophila cells with high esterase-activity was detected. We speculate that this highly active VBNC subpopulation is able to infect amoebae and human macrophages. (C) 2018 The Authors. Published by Elsevier Ltd.<\/span><\/p>\n

https:\/\/www.sciencedirect.com\/science\/article\/pii\/S0043135418303117?via%3Dihub<\/a><\/p>\n

 <\/p>\n

The post Differential development of Legionella sub-populations during short- and long-term starvation<\/a> appeared first on Facts About Water<\/a>.<\/p>\n

Source: Water Feed<\/p>\n

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What flow rates are available for emergency water treatment?<\/h3>\n
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AMPAC USA's emergency systems range from 1,500 GPD portable units to 50,000+ GPD trailer-mounted systems. Military-specification units are available for forward operating base deployment, producing potable water meeting EPA and WHO drinking water standards from virtually any source.<\/p>\n<\/div>\n<\/div>\n

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Are emergency RO systems suitable for disaster relief operations?<\/h3>\n
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Yes. AMPAC USA's emergency systems are used by FEMA, the U.S. military, and international NGOs for disaster relief. They treat flood water, contaminated groundwater, and brackish sources, removing bacteria, viruses, and chemical contaminants to produce safe drinking water on-site.<\/p>\n<\/div>\n<\/div>\n

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What power sources can emergency water purification systems use?<\/h3>\n
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AMPAC USA's emergency systems can run on generator power (120\/240V or 480V 3-phase), solar panels with battery backup, or vehicle power take-off (PTO). Low-power models consume as little as 0.5 kW, making them viable for off-grid deployment.<\/p>\n<\/div>\n<\/div>\n

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How durable are military-grade water purification systems?<\/h3>\n
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AMPAC USA's military systems are built to MIL-SPEC standards with stainless steel frames, powder-coated components, and UV-resistant materials. They are designed to operate in temperatures from -20\u00b0F to 120\u00b0F and are vibration-tested for transport in military vehicles.<\/p>\n<\/div>\n<\/div>\n<\/div>\n

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Conclusion<\/h2>\n

This post highlighted how emergency and military-grade water purification systems provide safe drinking water rapidly in the most challenging field conditions. For organizations requiring deployable water treatment capability, AMPAC USA engineers portable and trailer-mounted systems built to perform wherever they are needed. Contact our team at info@ampac1.com or (909) 548-4900 to discuss your emergency water treatment requirements.<\/p>\n<\/div>\n

Understanding Legionella Bacteria Water Systems<\/h2>\n

Water quality directly impacts health, productivity, and equipment longevity. Legionella Bacteria Water Systems represents one of the most important considerations for facility managers and homeowners alike. AMPAC USA engineers water treatment systems that address the full spectrum of contaminants\u2014from dissolved solids and heavy metals to biological threats and emerging compounds.<\/p>\n

Reverse osmosis technology forms the core of most advanced water treatment applications. RO membranes reject up to 99% of dissolved contaminants, including lead, arsenic, nitrates, fluoride, and chlorine byproducts. The semipermeable membrane allows only water molecules to pass, resulting in exceptionally pure water at the point of use.<\/p>\n

System sizing depends on daily volume requirements, source water TDS, temperature, and recovery rate targets. Industrial systems range from 500 GPD to multi-million GPD capacity, while residential units typically operate at 50\u2013200 GPD. Proper pre-treatment\u2014including sediment filtration, activated carbon, and antiscalant dosing\u2014extends membrane life and maintains peak performance. Regular monitoring of TDS rejection, pressure differential, and flow rate ensures systems operate within design parameters.<\/p>\n

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Frequently Asked Questions<\/h2>\n
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What is Legionella bacteria water systems?<\/h3>\n
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Legionella bacteria water systems refers to the technology and processes used to ensure water meets safety and quality standards for drinking, industrial, and environmental use. Reverse osmosis and advanced filtration are core methods.<\/p>\n<\/div>\n<\/div>\n

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How does reverse osmosis improve water quality?<\/h3>\n
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Reverse osmosis forces water through a semipermeable membrane that blocks dissolved salts, heavy metals, bacteria, and other contaminants\u2014delivering water with TDS as low as 5\u201310 ppm compared to tap water at 150\u2013500 ppm.<\/p>\n<\/div>\n<\/div>\n

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What contaminants does RO remove?<\/h3>\n
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RO systems remove lead, arsenic, nitrates, fluoride, chlorine, VOCs, bacteria, and most dissolved solids\u2014providing comprehensive protection against regulated and emerging contaminants.<\/p>\n<\/div>\n<\/div>\n

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How often should RO filters be replaced?<\/h3>\n
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Pre-filters (sediment and carbon) should be replaced every 6\u201312 months. RO membranes typically last 2\u20135 years depending on source water quality and system usage. Annual TDS testing confirms membrane performance.<\/p>\n<\/div>\n<\/div>\n

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Is AMPAC USA a reliable water treatment provider?<\/h3>\n
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AMPAC USA has over 25 years of experience designing and manufacturing commercial, industrial, and residential water treatment systems. All systems meet NSF\/ANSI standards and are backed by technical support and extended warranties.<\/p>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

Legionellae are among the most important waterborne pathogens in industrialized countries. Monitoring and surveillance of Legionella in engineered water systems is usually performed with culture-based methods<\/p>\n","protected":false},"author":1,"featured_media":87946,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[24],"tags":[22],"class_list":["post-983","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-water-filter","tag-ro"],"_links":{"self":[{"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/posts\/983","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/comments?post=983"}],"version-history":[{"count":2,"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/posts\/983\/revisions"}],"predecessor-version":[{"id":88185,"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/posts\/983\/revisions\/88185"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/media\/87946"}],"wp:attachment":[{"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/media?parent=983"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/categories?post=983"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ampac1.com\/blog\/wp-json\/wp\/v2\/tags?post=983"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}