Meditation and mindfulness may be as effective as medication for treating certain conditions

by Hilary A. Marusak, The Conversation

Credit: Unsplash/CC0 Public Domain

Many people look to diet trends or new exercise regimens—often with questionable benefit—to get a healthier start on the new year. But there is one strategy that's been shown time and again to boost both mood and health: meditation.

In late 2022, a high-profile study made a splash when it claimed that meditation may work as well as a common drug named Lexapro for the treatment of anxiety. Over the past couple of decades, similar evidence has emerged about mindfulness and meditation's broad array of health benefits, for purposes ranging from stress and pain reduction to depression treatments to boosting brain health and helping to manage excessive inflammation and long COVID-19.

Despite the mounting body of evidence showing the health benefits of meditation, it can be hard to weigh the science and to know how robust it is.

I am a neuroscientist studying the effects of stress and trauma on brain development in children and adolescents. I also study how mindfulness, meditation and exercise can positively affect brain development and mental health in youth.

I am very excited about how meditation can be used as a tool to provide powerful new insights into the ways the mind and brain work, and to fundamentally change a person's outlook on life. And as a mental health researcher, I see the promise of meditation as a low- or no-cost, evidence-based tool to improve health that can be relatively easily integrated into daily life.

Meditation requires some training, discipline and practice—which are not always easy to come by. But with some specific tools and strategies, it can be accessible to everyone.

What are mindfulness and meditation?

There are many different types of meditation, and mindfulness is one of the most common. Fundamentally, mindfulness is a mental state that, according to Jon Kabat-Zinn a renowned expert in mindfulness-based practices, involves "awareness that arises through paying attention, on purpose, in the present moment, non-judgmentally."

This means not ruminating about something that happened in the past or worrying about that to-do list. Being focused on the present, or living in the moment, has been shown to have a broad array of benefits, including elevating mood, reducing anxiety, lessening pain and potentially improving cognitive performance.

Mindfulness is a skill that can be practiced and cultivated over time. The goal is that, with repetition, the benefits of practicing mindfulness carry over into everyday life—when you aren't actively meditating. For example, if you learn that you aren't defined by an emotion that arises transiently, like anger, then it may be harder to stay angry for long.

The health benefits of meditation and other strategies aimed at stress reduction are thought to stem from increasing levels of overall mindfulness through practice. Elements of mindfulness are also present in practices like yoga, martial arts and dance that require focusing attention and discipline.

The vast body of evidence supporting the health benefits of meditation is too expansive to cover exhaustively. But the studies I reference below represent some of the top tier, or the highest-quality and most rigorous summaries of scientific data on the topic to date. Many of these include systematic reviews and meta-analyses, which synthesize many studies on a given topic.

Stress and mental health

Mindfulness-based programs have been shown to significantly reduce stress in a variety of populations, ranging from caregivers of people living with dementia to children during the COVID-19 pandemic.

Meta-analyses published during the pandemic show that mindfulness programs are effective for reducing symptoms of post-traumatic stress disorder, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder and depression—including the particularly vulnerable time during pregnancy and the postnatal period.

Mindfulness-based programs also show promise as a treatment option for anxiety disorders, which are the most common mental disorders, affecting an estimated 301 million people globally. While effective treatments for anxiety exist, many patients do not have access to them because they lack insurance coverage or transportation to providers, for instance, or they may experience only limited relief.

In addition to improving mood and lowering stress, mindfulness has been shown to elevate cognitive performance, cut down on mind wandering and distractibility and increase emotional intelligence.

It's important to note, however, that for those affected by mental or substance use disorders, mindfulness-based approaches should not replace first-line treatments like medicine and psychotherapy such as cognitive behavioral therapy. Mindfulness strategies should be seen as a supplement to these evidence-based treatments and a complement to healthy lifestyle interventions like physical activity and healthy eating.

How does meditation work? A look into the brain

Studies show that regular meditators experience better attention control and improved control of heart rate, breathing and autonomic nervous system functioning, which regulates involuntary responses in the body, such as blood pressure. Research also shows that people who meditate have lower levels of cortisol—a hormone involved in the stress response—than those who don't.

A recent systematic review of neuroimaging studies showed that focused attention meditation is associated with functional changes in several brain regions involved in cognitive control and emotion-related processing. The review also found that more experienced meditators had stronger activation of the brain regions involved in those cognitive and emotional processes, suggesting that the brain benefits improve with more practice.

A regular meditation practice may also stave off age-related thinning of the cerebral cortex, which may help to protect against age-related disease and cognitive impairment.

Limitations of meditation research

This research does have limits. These include a lack of a consistent definition for the types of programs used, and a lack of rigorously controlled studies. In gold-standard randomized controlled trials with medications, study participants don't know whether they are getting the active drug or a placebo.

In contrast, in trials of mindfulness-based interventions, participants know what condition they are assigned to and are not "blinded," so they may expect that some of the health benefits may happen to them. This creates a sense of expectancy, which can be a confounding variable in studies. Many meditation studies also don't frequently include a control group, which is needed to assess how it compares with other treatments.

Benefits and wider applications

Compared with medications, mindfulness-based programs may be more easily accessible and have fewer negative side effects. However, medication and psychotherapy—particularly cognitive behavioral therapy—work well for many, and a combination approach may be best. Mindfulness-based interventions are also cost-effective and have better health outcomes than usual care, particularly among high-risk patient populations—so there are economic benefits as well.

Researchers are studying ways to deliver mindfulness tools on a computer or smartphone app, or with virtual reality, which may be more effective than conventional in-person meditation training.

Importantly, mindfulness is not just for those with physical or mental health diagnoses. Anyone can use these strategies to reduce the risk of disease and to take advantage of the health benefits in everyday life, such as improved sleep and cognitive performance, elevated mood and lowered stress and anxiety.

Where to get started?

Many recreation centers, fitness studios and even universities offer in-person meditation classes. For those looking to see if meditation can help with the treatment of a physical or mental condition, there are over 600 clinical trials currently recruiting participants for various conditions, such as pain, cancer and depression.

If you want to try meditation from the comfort of your home, there are many free online videos on how to practice, including meditations for sleep, stress reduction, mindful eating and more. Several apps, such as Headspace, appear promising, with randomized controlled trials showing benefits for users.

The hardest part is, of course, getting started. However, if you set an alarm to practice every day, it will become a habit and may even translate into everyday life—which is the ultimate goal. For some, this may take some time and practice, and for others, this may start to happen pretty quickly. Even a single five-minute session can have positive health effects.

Provided by The Conversation 

This article is republished from The Conversation under a Creative Commons license. Read the original article.

How effective is mindfulness for treating mental ill-health? And what about the apps?

How politics seep into daily life, negatively affecting mental health

by American Psychological Association

Conceptual Figure Demonstrating How Emotion Regulation Can Be Used to 

Reduce Negative Emotions in Response to Stressful Political Events, With a 

Resulting Trade-Off Between Well-Being and Political Action. Note. Although 

negative emotional responses to politics should accumulate and promote 

worse well-being, these emotions may also drive political action. As such,

 emotion regulation can come with a trade-off, whereby people are able to

 protect their well-being, but coming with a cost to political action. 

Credit: Journal of Personality and Social Psychology (2023). 

https://doi.org/10.1037/pspa0000335

The stress of following daily political news can negatively affect people's mental health and well-being, but disengaging has ramifications, too, according to research published by the American Psychological Association.

There are strategies that can help people manage those negative emotions—such as distracting oneself from political news—but those same strategies also reduce people's drive to act on political causes they care about, the research found.

"When it comes to politics, there can be a trade-off between feeling good and doing good," said Brett Q. Ford, Ph.D., an assistant professor of psychology at the University of Toronto. "Protecting oneself from the stress of politics might help promote well-being but it also comes at a cost to staying engaged and active in democracy."

The research was published in the Journal of Personality and Social Psychology.

Previous research and polling data have found that politics can be a major stressor in people's lives, according to the researchers. However, most of that research has focused on major political events such as presidential elections. Ford and her colleagues wanted to explore the emotional and mental health effects of everyday political news and how people use different strategies to manage those negative emotions.

"Politics isn't just something that affects people every four years during election season—it seems to seep into daily life. But we just don't know much about the day-to-day impact politics might have," Ford said.

To learn more, she and her colleagues began by asking a politically diverse sample of 198 Americans to answer a series of questions each night for two weeks about the political event they thought about most that day, the emotions they felt in response, how they managed those emotions, their general psychological and physical well-being that day, and how motivated they felt to engage in political action.

Overall, the researchers found that thinking about daily political events evoked negative emotions in participants—even though the survey question had not asked participants to think of negative political events. Participants who experienced more politics-related negative emotions reported worse day-to-day psychological and physical health on average—but they also reported greater motivation to act on political causes by doing things such as volunteering or donating money to political campaigns.

The survey also asked participants about several strategies they might have used to manage their negative emotions, including distracting themselves from the news and "cognitive reappraisal," or reframing how they thought about a news event to make it seem less negative. Participants who successfully used these strategies to manage their negative emotions reported better daily well-being, but also less motivation to take political action.

Next, the researchers replicated these results over three weeks with a larger group of 811 participants that included not only Democrats and Republicans but also people affiliated with a different political party or no party.

In a second set of experiments, Ford and her colleagues asked participants to watch political news clips from the highest-rated liberal and conservative-leaning news shows rather than simply asking them to report on politics they had encountered. In these experiments, participants watched a clip from either the Rachel Maddow Show (for liberal participants) or Tucker Carlson Tonight (for conservative participants).

In a first experiment, the researchers found that participants who watched the political clip experienced more negative emotions than those who watched a neutral, non-political news clip, and reported more motivation to volunteer for political causes or take other political action. The effect held true for participants across political parties.

In a final experiment, the researchers asked participants to try out several different emotion regulation strategies as they watched the clips—distraction, cognitive reappraisal or acceptance of their negative feelings. Replicating the results from the diary studies, the researchers found two of the strategies, distraction and cognitive reappraisal, consistently reduced participants' negative emotions which in turn predicted better well-being, but indirectly reduced the likelihood that they would want to take political action.

Overall, the results suggest that politics have a significant daily effect on many Americans' health and well-being, according to the authors.

"Modern politics—its daily controversies, incivility and ineptitude—puts a regular emotional burden on Americans," said Matthew Feinberg, Ph.D., a coauthor of the paper and professor of organizational behavior at the Rotman School of Management at the University of Toronto.

This has important implications, particularly for activists who wish to get people involved in advocating for political causes without harming their mental health, according to the researchers.

"In a way, this is a trade-off between individual wellness and collective wellness," Ford said.

"We are working toward identifying strategies that people can use to protect their own well-being without coming with costs to the broader collective. This paper begins to address this by studying emotional acceptance—a strategy that is linked with greater well-being for individuals in daily life, and which doesn't seem to come with consistent costs to collective action. It is important that people have a variety of tools they can use to manage the chronic stress of day-to-day politics while also maintaining the motivation to engage with politics when needed."

Further research should examine the effects of politics on well-being in different countries, the researchers suggest. "The U.S. faces high levels of political polarization in a largely two-partysystem and a media often revolving around inciting moral outrage," Feinberg said. "It would be interesting to see the extent to which daily politics would affect citizens from in other countries that are less polarized or with different political systems."

More information: Brett Q. Ford etal, The Political is Personal: The Costs of Daily Politics, Journal of Personality and Social Psychology (2023). DOI: 10.1037/pspa0000335. On PsyArXiv: psyarxiv.com/hdz97/

Journal information: Journal of Personality and Social Psychology 

Provided by American Psychological Association 

Study: Political polarization doesn't dominate people's perceptions of COVID-19

Largest decentralized study of its kind shows high levels of engagement with study app

by Huma Ltd

Fenland COVID-19 study flow diagram. 

Credit: Journal of Medical Internet Research (2022). DOI: 10.2196/40602

A new study, which was a collaboration between Huma Therapeutics and the Medical Research Council Epidemiology Unit at the University of Cambridge, shows that participants using Huma's clinical trial platform had high, sustained levels of engagement in an observational, fully remote COVID-19 study.

The study, published in the Journal of Medical Internet Research, involved 62.61% (2524/4031) participants from the longitudinal Fenland study, making it the largest population-based study to-date exploring how digital technologies can support population research.

From the participants, 90.21% (2277/2524) completed the app-based onboarding process and signed e-consent. In addition to using the study app (available for both iPhone and Android), each was also sent a digital pulse oximeter (to measure blood oxygen levels) and thermometer. They were provided with remote set-up assistance and were asked to record the following biomarkers:

• blood oxygen saturation (three times per week)
• body temperature (three times per week)
• resting heart rate (three times per week)
• activity levels (measured passively)
• respond to monthly questionnaires
• blood spot samples to test for the presence of coronavirus antibodies.

Participants had a positive experience with the study app, finding it easy to use and quick to report measurements and symptoms. They took part in the observational study for at least 6 months and most kept completing measures until asked to stop; there was minimum drop off in engagement over the study period. On average, people used the study app for 34.5 weeks (7.9 months), with only 2.5% of participants withdrawing from the study. It was interesting to see a higher engagement rate amongst the participants aged over 65.

Dr. Arrash Yassaee, Global Clinical Director at Huma, said, "Huma is committed to building robust clinical and scientific evidence for its technology. The high level of engagement and retention we've seen in this study is very encouraging. User-friendly clinical trial technologies such as Huma's have great potential to transform population-based health research by increasing access and reducing the burden on participants. This kind of data collection is incredibly valuable for understanding health and disease processes in the real world and gathering insights that can make a difference to people's lives."

Dr. Kirsten Rennie, a Senior Research Associate at MRC Epidemiology Unit and an expert in quantitative measures of physical activity and diet, who led the study said, "Enrolment and retention in traditional cohort-based observational studies is a constant challenge and participation has been declining in recent years. Here we saw not only great enrolment and retention, but also engagement which has helped us create a useful checklist for other researchers to follow."

The COVID-19 pandemic accelerated interest in the use of digital health solutions for remote health monitoring. But while these technologies have shown benefits for patients with chronic or acute health conditions, less is known about their utility in population-based health research, where it is becoming increasingly hard to recruit participants and keep them engaged over months or even years.

More information: Kirsten L Rennie et al, Engagement With mHealth COVID-19 Digital Biomarker Measurements in a Longitudinal Cohort Study: Mixed Methods Evaluation, Journal of Medical Internet Research (2022). DOI: 10.2196/40602

Journal information: Journal of Medical Internet Research 

Provided by Huma LtdUnderstanding how the perception of risks and benefits influences cancer clinical trial withdrawal outcomes

Paying people to take COVID vaccine worked well, study finds

by Mary Van Beusekom, University of Minnesota

Regression-estimated effects of informing US residents about state vaccination incentive programs on further COVID-19 vaccination, other health behaviors, morals and civic responsibility, and perceived safety, efficacy and trust. The figure is based on experimental data from a general population sample of US residents in 12 states that introduced incentive programs for COVID-19 vaccination. The figure shows regression-estimated effects of the incentives condition (informing participants about the existence of incentive programs in their state) relative to the control condition, as pre-registered. All regressions use controls consisting of gender, age, education, employment status, income and state of residence in 2021 (see Extended Data Fig. 3 for results without controls). The blue dots indicate the estimated impact in standard deviations on the respective variables; all outcomes are defined as pre-registered. Error bars represent 95% confidence intervals (two-sided CI: mean ± 1.96 s.e.) from OLS regressions with heteroscedasticity-robust standard errors. The dashed gray lines indicate the threshold for small effect sizes of 0.2 standard deviations (Cohen’s d). The sample sizes for the control and incentives conditions are n incentives = 1,521 and n control = 1,541. Credit: Nature (2023). DOI: 10.1038/s41586-022-05512-4

A study finds that paying people to take a first dose of a COVID-19 vaccine didn't lower the likelihood of seeking the second or third dose or of other positive health behaviors and didn't erode morals, sense of civic duty, or feelings of self-determination.

The study, led by Swiss and Swedish researchers, was published yesterday in Nature. The researchers note that, while financial incentives to encourage healthy and prosocial behaviors often generate initial behavioral change, critics say that they can corrode prosocial motivations, lead to moral decay, and increase feelings of coercion, reducing the likelihood of practicing healthy behaviors without a payment.

The team offered 1,131 Swedish participants in a previous randomized, controlled trial (RCT) 200 Swedish krona (SEK), or roughly $24 US, to receive a first COVID-19 vaccine dose within 30 days. That group was compared with 3,888 matched participants not offered the incentive.

Just as likely to seek subsequent doses

The researchers combined the RCT data with vaccination records on second-dose uptake and survey results from January (first dose uptake) and June 2022 (third dose). A total of 726 participants in the financial incentive group and 2,512 controls responded to the first survey, and 606 and 2,100, respectively, completed the second.

The payment boosted uptake by four percentage points 30 days after the trial ended. Uptake remained elevated for at least three months.

The authors identified no negative effects of financial incentives on subsequent planned or actual COVID-19 vaccine uptake or timing, morals, sense of civic duty, trust in vaccination providers or in the safety and effectiveness of vaccines, attitudes toward financial incentives, or feelings of self-determination or coercion.

Nor was there evidence that incentives received in the previous five months for behaviors such as flu shot uptake or blood donation had any negative effects on the decision to receive the COVID-19 vaccine. "Our findings inform not only the academic debate on financial incentives for behavior change but also policy-makers who consider using financial incentives to change behavior," they wrote.

More information: Florian H. Schneider et al, Financial incentives for vaccination do not have negative unintended consequences, Nature (2023). DOI: 10.1038/s41586-022-05512-4

Journal information: Nature 

Provided by University of Minnesota People were hesitant about rather than opposed to the COVID-19 vaccine, study finds

Looking to 2023: What lessons have we learned from the COVID-19 pandemic in the last three years?

by Jeremy Lim, Bryan Chow and Anne Goei, National University of Singapore

Credit: Unsplash/CC0 Public Domain

Last year, German Chancellor Olaf Scholz in a speech on global geopolitics popularized the German word "zeitenwende," which refers to a "turning point" and time for change.

The COVID-19 pandemic has likewise brought about seismic change in how the world looks at global health security and brought to the forefront the critical need for public health capabilities nationally and globally. "Never Again" has been the rallying cry of communities, businesses and public officials the world over and this momentum offers opportunities to fundamentally redefine pandemic preparedness and response.

What have we learned in the last three years?

There are numerous lessons cutting across all sectors of life. We summarize them in five key insights: pre-emptive investment in health security, nimbleness, trust, global cooperation and commitment to equity.

1. Pre-emptive investment

COVID-19 has shown that proactive preparedness remains key to managing future pandemics. Many countries challenged with lesser outbreaks in recent years, preserved the responding infrastructure which positioned them well for the initial containment of COVID-19.

South Korea and Senegal, with prior lessons from the Middle East Respiratory Syndrome (MERS) and Ebola respectively, were able to manage well whilst geographies in Asia affected by the Severe Acute Respiratory Syndrome (SARS) such as Hong Kong and Singapore all had regularly rehearsed response plans in place which could be adapted quickly for COVID-19.

2. Nimbleness

No country can afford to maintain standing resources to deal with Disease X (a term popularized by Singapore Prime Minister Lee Hsien Loong to describe the next pandemic) but creativity and nimbleness in adapting and re-purposing existing infrastructure can go a long way. Project Warp Speed harnessed decades of research into mRNA vaccines intended for cancer care and adapted these for SARS-CoV-2, the virus which causes COVID-19.

Contact tracing systems deployed globally leveraged geospatial technologies used in ride-hailing and other consumer applications. Locally, physical infrastructure such as hotels, holiday chalets, military camps and convention halls were quickly configured to house thousands of COVID-19 patients to mitigate transmission and prevent overwhelming the healthcare system.

The setting up of a community wastewater surveillance program by the NUS Environmental Research Institute is another example, harnessing existing resources to set up a quick system of detection and enabling rapid ringfencing of infections.

3. Trust

Mahatma Gandhi, India's independence leader, exhorted the world: "The moment there is suspicion about a person's motives, everything he does becomes tainted." The pandemic has richly illustrated how corrosive mistrust can be, manifesting in multiple forms such as misinformation campaigns, conspiracy theories and the like.

Open communication and collaborative partnerships built on trust between government agencies, public health entities, religious and community groups, and the public are necessary conditions for successfully combating a pandemic. Sadly, many countries did poorly on this front with delays in vaccinations and inappropriate public health interventions all too common. Even more perniciously, some actors "politically weaponized" public health for their own nefarious purposes, worsening the trust deficit.

The reality of fast-spreading disease is that coordinated responses across all fronts are critical, and "trust is the glue." Trust and the community that trust builds cannot be achieved overnight or only in crises. As Stephen Covey, author of the best-selling The Speed of Trust drily notes, "The best time to plant a tree is twenty years ago. The second-best time is today." Trust barometers show we are, as a world, moving in the wrong direction and this has to be reversed.

4. Global cooperation

Pandemics can no longer be left to individual nations to handle. Widespread migration and travel mean diseases now spread much more quickly across borders, demanding a collective response internationally. Supranational public health agencies such as the World Health Organization (WHO) need to have larger roles and responsibilities as well as resources in pandemic surveillance and response.

The International Health Regulations, the only legally binding health-related legislation was shown to be woefully inadequate and a new order is needed. That said, international organizations are only as strong as their members want them to be, and member states have to determine they are better together under the central collective leadership and direction of a strong WHO than isolated and apart with an enfeebled WHO whose pronouncements are routinely disregarded.

Beyond strengthening the global peak public health body, public health networks should be developed regionally. Resource sharing among existing regional associations is a good start and it is encouraging that within our region, the Association of Southeast Asian Nations (ASEAN) has agreed to establish the ASEAN Centre for Public Health Emergencies and Emerging Diseases (ACPHEED).

At the people-to-people level, the Building Alliances for Pandemic Response (Public Health) Asia [ALPHA] program hosted by NUS will facilitate greater cooperation amongst leaders in the region, allowing an intersection of public health leadership, strong partnerships, and cross-country collaboration.

5. Commitment to equity

Moving forward, to truly achieve global health security, we must ensure equitable health development. Poignantly in Singapore, despite early laudations of stellar pandemic control, we saw an unprecedented outbreak within the migrant worker dormitories.

This reinforced a sobering truth—we are only as secure as the most vulnerable groups among us. United Nations Deputy Secretary-General Amina Mohammed reminded us, "Remember, we are in this together. No one will ever be truly safe until everyone is safe." And this truism holds at the local, national, regional and global levels.

Operationally, Universal Health Coverage or UHC for short is the right overarching framework to steer towards equitable health for all and all countries should be supported to realize this for their citizens. Globally for health security, the Microsoft co-founder turned philanthropist Bill Gates has proposed a global governance framework.

This framework would include establishing a permanent organization of experts to mount a coordinated response to a dangerous outbreak at any time in any country, conducting resilience and preparedness drills in between, a Global Epidemic Response and Mobilization (GERM) team, as well as mechanisms to accelerate vaccine and diagnostics developments and availability particularly in low and middle income countries.

The great American epidemiologist Larry Brilliant has said "outbreaks are inevitable, but pandemics are optional." Early in 2020, a group of public health academics gathered in NUS to discuss whether a two-week global lockdown would avoid the worsts of COVID-19. We decided that it would be highly effective from a public health perspective but that narrow national interests and partisan politics would not permit this reality. We have as a human species learned so many painful lessons these last three years. Will we do better with the next outbreak?

Provided by National University of Singapore 

As COVID-19 becomes routine, Africa readies for next crisis

LEGIONAIRES DISEASE

Water systems study finds Legionella in 41% of samples

by Flinders University

Light microscopic images of trophozoites (active form; image A, B and D) and 

cysts (dormant form; image: C and D circular in shape) of Acanthamoeba

(image A, B and C) and Vermamoeba vermiformis (image D) shown at 100 times

 magnification. Credit: Flinders University

A new study of domestic and hospital drinking water systems found Legionella in 41% of samples—with Flinders University researchers making a key connection between the pathogen's co-existence with a "host" microorganism in all samples tested.

The study found Legionella bacteria "infect the amoeba host and then once inside these hosts are protected from disinfection strategies," says Flinders University Associate Professor of Environmental Health Harriet Whiley, a co-author of the new journal article in Water Research.

Researchers tested for Legionella and its likely amoebae hosts in 140 samples of water or biofilm (the slime found on showerheads and end of faucets) to understand how the potentially dangerous bacterium colonizes and proliferates in both domestic and hospital plumbing and poses a threat to human health.

Legionnaires' disease is a severe pneumonia-like infection that can be fatal. Globally the number of Legionnaires' disease cases is increasing, with elderly and immunocompromised people at the highest risk.

"It is vital that we strive to improve the management of our water distribution systems, particularly in high risk setting such as hospitals, to protect vulnerable populations," says Associate Professor Whiley, from the Flinders College of Science and Engineering.

"Having a better understanding of the relationships between these amoebae and Legionella is an important step in improving future water treatment processes aimed at controlling Legionella and preventing Legionnaires disease."

L. pneumophilia is the main cause of Legionnaires' disease and is not transmitted from person to person but caused by inhalation or aspiration of contaminated water.

Maintenance and monitoring of water systems is a common preventive step to reduce public risk.

"To our knowledge, this is the first time the amoebae Allovahlkampfia and Stenamoeba have been demonstrated as hosts of L. pneumophila in Australian drinking water," says Flinders University Ph.D. candidate Muhammad Atif Nisar, who conducted the study.

The findings support the need further research to investigate the prevalence of Legionella as well as free-living amoebae in domestic and commercial water systems and to improve guidelines to better control water systems and safeguard the public health.

"Free-living amoebae are ubiquitous in the environment and cause both opportunistic and non-opportunistic infections in humans. Some amoebae are the natural reservoirs of opportunistic plumbing pathogens, such as Legionella pneumophila," says Mr. Atif Nisar.

"There is a need for future research to improve disinfection strategies against amoeba to reduce their colonization within building drinking water systems."

Up to 75% of the drinking water or biofilm samples tested positive for free-living amoebae. This included V. vermiformis which was present in 55% of samples and Acanthamoeba was present in 11%.

As well as being hosts for Legionella, Acanthamoeba and V. vermiformis are pathogens that can cause severe eye infections, with contact lens users and immunocompromised individuals at greatest risk.

The water samples were collected from showers and hand basins located in domestic houses and hospitals across New South Wales and South Australia.

These results demonstrate the importance of amoebae in engineered water systems, both as a pathogen and as a reservoir of Legionella.

"Future water management protocols should incorporate improved treatment strategies to control amoebae to reduce the risk to end-users," adds Mr. Atif Nisar.

More information: Muhammad Atif Nisar et al, Molecular screening and characterization of Legionella pneumophila associated free-living amoebae in domestic and hospital water systems, Water Research (2022). DOI: 10.1016/j.watres.2022.119238

Provided by Flinders University Investigators identify optimal conditions for growth of Legionella bacteria