Taking a look at Legionella bacteria and its sources, impact

twoLegionellosis is a respiratory disease caused by Legionella bacteria. Sometimes the bacteria cause a serious type of pneumonia (lung infection) called Legionnaires’ disease. The bacteria can also cause a less serious infection called Pontiac fever that has symptoms similar to a mild case of the flu. The bacteria can be found in most water systems, and is fairly common. Below are a few pieces that discuss the bacteria and the disease.

Legionnaires’ disease: Can it be found in water systems? says that “it is important to note that Legionella can be effectively controlled. When controlled properly, the bacterium represents a minimal health risk and emergency actions should not be required. The key to preventing an outbreak of Legionnaires’ disease starts with the municipal water system.  Additionally, a good building water management plan, responsibly implemented, should control the bacteria from colonizing to dangerous levels within individual building water systems.”

Monochloramine for controlling Legionella in biofilms: how much we know? concludes that “The presence of Legionella within a biofilm makes eradication from water system very difficult. Among the antimicrobial agents, monochloramine (MC) seems to be more effective for decreasing Legionella within the biofilms in vitro as well as in model plumbing systems. As of to date there are no published reviews on this topic, a critical and comprehensive update on the progress in the field is necessary.”

Legionella Control in Institutional Water Systems suggests that “a residual of chlorine-based disinfectant is indispensable because it is effective against the majority of bacteria and viruses and other germs that commonly cause waterborne disease, and it provides continuing protection as water journeys from the treatment plant to your glass.”


·         Relationship between antibiotic- and disinfectant-resistance profiles in bacteria harvested from tap water.

·          Water heater temperature set point and water use patterns influence Legionella pneumophila and associated microorganisms at the tap

Studies explore the impact of environment on productivity

The environment can have a profound impact on productivity, and below are links to a series of studies that explore this with a variety of approaches.

The office experiment: Can science build the perfect workspace? – Windows, desks and employees are being wired up in a quest to create healthy, evidence-based environments. is a study that seeks to determine  how the indoor environment influences health, well-being and performance, from stress to sleep quality, physical fitness to productivity.  Related podcast.

Airborne Respiratory Diseases and Mechanical Systems for CONTROL OF MICROBES notes that airborne respiratory pathogens and diseases in health care facilities are numerous and dangerous. HVAC systems are critical in controlling them.

BUILDING INVESTMENT DECISION SUPPORT (BIDS™): Cost-Benefit Tool to Promote High Performance Components, Flexible Infrastructures and Systems Integration for Sustainable Commercial Buildings and Productive Organizations is a study that shows the cost of dirty air in the work place is much more than the cost of energy per person.

Also: What Your CEO Is Reading: Office Science; Fonts Save the World; Luxury of Work

Forced migration creates health problems, enhances spread of disease

twoForced migrations designed to contain disease generally don’t work as planned, as several studies and articles listed below show.

Refugee camps a “breeding ground” for illnesses: “United Nations aid agencies say hundreds of thousands of refugees are living in unacceptable conditions at camps. These people fled their homes because of violence in the Middle East and Africa. The U.N. agencies are blaming serious food and water problems at many refugee camps for the spread of life-threatening diseases. Officials say cholera, malaria and jaundice — combined with malnutrition — are threatening refugees who had hoped to be safe after they entered the camps.”

Refugees, Forced Displacement, and War notes that “women make up high proportions of refugee and internally displaced populations, and they suffer unique consequences of war and conflict because of gender-based violence, discrimination, and caretaking roles. Refugee women are especially vulnerable to infectious disease, as well as threats to their mental health and physical safety.”

Mental Health at Refugee Health Technical Assistance Center says that “Since 2000, over 600,000 refugees have been settled throughout the U.S., coming from countries as disparate as the former Soviet Union, Somalia, and Vietnam. The often traumatic reasons for leaving the host country as well as the potentially long and hazardous journey and process of resettlement increase the risk for refugees to suffer from a variety of mental health issues. While the screening for and treatment of infectious diseases has been studied and practiced for decades, the identification and treatment of mental health problems has lagged far behind. Complex and varied cultural contexts and languages, scattered refugee populations, and the relative lack of evidence-based interventions have made it difficult to carry out concerted and standardized efforts.”

Restricting population movement is a largely ineffective way of containing disease, yet governments sometimes resort to it where health crises emerge, according to Health crises and migration. In 1951, the World Health Organization (WHO) adopted the International Sanitary Regulations – renamed International Health Regulations (IHR) in 1969 – with the objective of maximum prevention of the spread of infectious diseases with minimal disruption of travel and trade. The assumption was that “migration was unidirectional, and that diseases could be stopped at international borders. Individual and collective responses to health crises contribute to an orderly public health response that most times precludes the need for large-scale displacements. … Despite their adherence to the IHR, countries sometimes revert to isolation and restriction, threatening or deciding to close borders or to impose travel restrictions in an attempt to prevent infections from entering their territory. Here’s an audio version of the article.

Also: Tuberculosis in migrants moving from high-incidence to low-incidence countries: a population-based cohort study of 519 955 migrants screened before entry to England, Wales, and Northern Ireland


Water is a source of secondary infection that cannot be overlooked

threeWater is a source of secondary infection. Chlorination is commonly used to control levels of bacteria in drinking water; however, viable bacteria may remain due to chlorine resistance, according to a piece at PubMed (Relationship between antibiotic- and disinfectant-resistance profiles in bacteria harvested from tap water.) What is concerning, the piece notes, “is that surviving bacteria, due to co-selection factors, may also have increased resistance to common antibiotics. This would pose a public health risk as it could link resistant bacteria in the natural environment to human population. . . . The presence of chlorine-resistant bacteria surviving in drinking-water systems may carry additional risk of antibiotic resistance.”

Healthcare costs for infections linked to bacteria in water supply systems are rising at Science Daily, is a  new analysis of 100 million Medicare records from US adults aged 65 and older reveals rising healthcare costs for infections associated with some disease-causing bacteria, such as Legionella, which can live inside drinking water distribution systems and household plumbing.

Impact of Water Chemistry, Pipe Material and Stagnation on the Building Plumbing Microbiome at PLOS One reports that “a unique microbiome establishes in the portion of the potable water distribution system within homes and other buildings (i.e., building plumbing). . . .  Data were examined across utilities to identify a true universal core, special core, and peripheral organisms to deepen insight into the physical and chemical factors that shape the building plumbing microbiome.”