What Is: Zoonotic Spillover

Scientific Frontline: Extended "At a Glance" Summary: Zoonotic Spillover

The Core Concept: Zoonotic spillover is the successful transmission of a pathogenic entity—such as a virus, bacterium, or parasite—from a non-human animal reservoir into a human population. This rare but consequential event occurs when a pathogen successfully crosses the strict biological boundary between species.

Key Distinction/Mechanism: Unlike regular endemic transmission, a zoonotic spillover is dictated by the "Spillover Barrier Model." A pathogen must overcome a hierarchical series of formidable biological and ecological obstacles. Spillover only succeeds when specific vulnerabilities across these barriers perfectly align in both space and time, allowing the pathogen to bind to human cellular receptors and evade immediate immune destruction.

Major Frameworks/Components:

• The Three Layers of Biological Barriers: The zoonotic reservoir layer (host density and distribution), the environmental and vector layer (pathogen persistence in abiotic conditions), and the recipient spillover host layer (human exposure, susceptibility, and cellular infection dynamics).
• Viral Shedding Dynamics: Pathogens are often excreted in discrete temporal and spatial "pulses" triggered by demographic shifts or environmental stress.
• Epidemiological Transmission Models:
• SIR (Susceptible-Infectious-Recovered): Seasonal epidemic cycles driven by natural host population fluctuations.
• SIRS (Susceptible-Infectious-Recovered-Susceptible): Cyclical circulation driven by waning immunity within a reservoir.
• SILI (Susceptible-Infectious-Latent-Infectious): Persistent infections triggered by stress-induced viral reactivation.

Study Finds Concerning Rise in U.S. Teen Obesity over a Decade

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Scientific Frontline: Extended "At a Glance" Summary: U.S. Adolescent Obesity Trends (2013–2023)

The Core Concept: A comprehensive epidemiological study revealing a concerning decade-long rise in U.S. adolescent obesity, coupled with a paradoxical decline in active weight-loss attempts among high school students. It underscores a generational shift where higher body weights are becoming more common while motivation to manage weight is steadily declining.

Key Distinction/Mechanism: Unlike general health overviews, this research analyzes data from over 85,000 students to pinpoint a specific behavioral gap: while overall teen obesity increased from 13.7% to 15.9% over a decade, the proportion of adolescents actively attempting to lose weight decreased from 47.7% to 44.5%.

Major Frameworks/Components:

• Demographic Variances: Tracks obesity disparities across race and ethnicity, noting peak rates in Black (21.2%) and Hispanic (20.2%) adolescents, and a doubled prevalence in Asian teens (from 5.6% to 11%).
• Gender and Grade Disparities: Highlights that while female adolescents are more likely to attempt weight loss than males, their engagement is dropping. Weight-loss efforts declined most sharply among 10th and 12th graders.
• Clinical Comorbidities: Correlates adolescent obesity with severe, long-term health conditions, including diabetes, hypertension, sleep apnea, and psychological challenges such as depression and low self-esteem.
• The Behavioral Shift: Documents the troubling divergence between rising clinical obesity rates and waning student motivation to pursue weight management, a pressure potentially complicated by social media and body dissatisfaction.

Antibiotics can affect the gut microbiome for several years

Researchers have now collected a second sample from nearly half of the participants. The analyses are expected to reveal which effects remain after 16 years.
Photo Credit: Sandra Gunnarsson

Scientific Frontline: Extended "At a Glance" Summary: Long-Term Antibiotic Impact on the Gut Microbiome

The Core Concept: Antibiotic treatments can alter the composition and diversity of the bacterial community in the gastrointestinal tract, known as the gut microbiome, with measurable disruptions persisting for four to eight years after a single course of treatment.

Key Distinction/Mechanism: While the short-term disruptive effects of antibiotics on gut flora are well-documented, this research establishes the protracted nature of this ecological footprint. The mechanism of disruption varies significantly by antibiotic class; drugs such as clindamycin, fluoroquinolones, and the narrow-spectrum flucloxacillin cause substantial, long-lasting decreases in bacterial diversity, whereas commonly prescribed options like penicillin V result in only minor, transient changes.

Major Frameworks/Components: 

• Epidemiological Data Linkage: The methodology relies on cross-referencing longitudinal, individual-level pharmacy dispensing data with large-scale biobank microbiome mapping (utilizing Swedish population-based cohorts like SCAPIS and SIMPLER).
• Bacterial Diversity Reduction: The core metric for microbiome health in the study is the quantifiable decrease in the diversity of bacterial species present in the gut following exposure to specific antimicrobials.
• Antibiotic Stratification: The framework evaluates post-treatment recovery times by differentiating the ecological impact based on the specific spectrum and chemical class of the antibiotic administered.

No overdiagnosis of ADHD, say experts

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Scientific Frontline: "At a Glance" Summary: ADHD Diagnosis Trends and Prevalence

• Main Discovery: There is no robust evidence supporting the narrative of ADHD overdiagnosis in the UK; instead, systemic underdiagnosis, undertreatment, and severely delayed clinical assessments are the predominant healthcare challenges.
• Methodology: Researchers analyzed English National Health Service (NHS) administrative records and compared domestic diagnostic rates against internationally standardized diagnostic criteria, while incorporating clinical evaluations and input from individuals with lived experience.
• Key Data: International baseline prevalence for ADHD is approximately 5 percent in children and 3 percent in adults, but English NHS diagnosis rates remain well below these thresholds. Furthermore, 27 percent of diagnosed youth waited one to two years for assessment, and 14 percent waited two to three years.
• Significance: The popular misconception of overdiagnosis misleads policymakers and obscures the critical ethical issue of unmet medical needs, as untreated ADHD severely increases the risks of academic failure, substance abuse, criminality, and suicidal behavior.
• Future Application: Healthcare systems must implement a risk-stratified stepped-care approach, increase funding, and improve multidisciplinary clinical training to efficiently expand access to accurate diagnostic and therapeutic care.
• Branch of Science: Psychiatry, Epidemiology, and Public Health.
• Additional Detail: While systemic overdiagnosis is statistically unsupported, individual misdiagnosis remains a clinical risk, particularly when evaluations rely heavily on self-reporting or when excessive public wait times drive patients toward less rigorous private sector assessments.

Arrival of Homo Erectus may have triggered Mosquitoes’ taste for human blood

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Scientific Frontline: Extended "At a Glance" Summary: Mosquito Evolution and Early Hominins

The Core Concept: The arrival and sustained presence of early human ancestors (Homo erectus) in the prehistoric Southeast Asian landmass of Sundaland approximately 1.8 million years ago likely triggered an evolutionary shift in Leucosphyrus mosquitoes, causing them to adapt to feeding on human blood.

Key Distinction/Mechanism: While the ancestors of these mosquitoes originally fed almost exclusively on non-human primates within humid forest canopies, global climate shifts toward cooler, drier, and more open environments forced them to become flexible feeders. This newly adapted ground-feeding behavior, combined with the arrival of early hominins, served as the biological bridge that led certain mosquito species to become highly anthropophilic (human-targeting) vectors for malaria.

Major Frameworks/Components: 

• Genomic Sequencing: Researchers sequenced the genomes of 38 mosquitoes across 11 species within the Leucosphyrus group, collected between 1992 and 2020.
• Behavioral Mapping: The study categorized species across three blood-feeding behaviors—human, non-human primate, and mixed—to map the evolutionary host preference.
• Paleoclimatic Modeling: The research integrated environmental data, demonstrating how the shift from the permanently humid Pliocene to the seasonal, open-forest conditions of the Pleistocene acted as an environmental trigger for mosquito adaptation.

Children with poor oral health more often develop cardiovascular disease as adults

By analyzing data on 568,000 children, researchers at the UCPH have found that children with poor dental health have up to a 45% higher incidence of cardiovascular disease as adults.
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Scientific Frontline: Extended "At a Glance" Summary: The Link Between Childhood Oral Health and Adult Cardiovascular Disease

The Core Concept: Extensive epidemiological research demonstrates a strong statistical correlation between poor childhood oral health—specifically multiple tooth cavities and severe gingivitis—and a significantly increased risk of developing cardiovascular disease and type 2 diabetes in adulthood.

Key Distinction/Mechanism: The primary proposed mechanism driving this association is systemic inflammation. Researchers hypothesize that early exposure to high inflammatory levels from dental caries and gum disease alters the body's long-term immune response, while oral bacteria may directly trigger systemic inflammatory cascades that accelerate atherosclerotic cardiovascular disease over time.

Origin/History: A 2026 cohort study conducted by researchers at the University of Copenhagen (published in early 2026) analyzed longitudinal data from 568,778 Danish individuals born between 1963 and 1972, tracking their health outcomes through 2018 to establish the long-term impacts of early oral health.

People's gut bacteria worse in areas with higher social deprivation

Living in a poorer neighborhood in the could impact the make-up of your gut microbiome, potentially leading to worse health.
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Scientific Frontline: Extended "At a Glance" Summary: The Gut Microbiome and Social Deprivation

The Core Concept: Living in socially deprived neighborhoods is directly correlated with a less diverse gut microbiome, notably characterized by a deficiency in essential, short-chain fatty acid-producing bacteria.

Key Distinction/Mechanism: While diet is a known modifier of gut health, this mechanism highlights how broader environmental and socioeconomic stressors (e.g., chronic stress, financial strain, and resource scarcity) biologically alter gut composition. Specifically, social deprivation is linked to a reduction in butyrate-producing bacterial species—such as Lawsonibacter and Intestinimonas massiliensis—which are critical for controlling inflammation, maintaining energy balance, and regulating communication between the gut and the brain.

Origin/History: A collaborative study published in February 2026 in npj biofilms and microbiomes by researchers from King's College London and the University of Nottingham established this link. The study analyzed the gut profiles of 1,390 participants from the TwinsUK registry and mapped them against geographical socioeconomic status.

Toxic exposure creates disease risk over 20 generations

Sarah De Santos, an undergraduate research assistant, and Professor Michael Skinner work together in the laboratory.
Photo Credit: Washington State University

Scientific Frontline: "At a Glance" Summary: Intergenerational Disease Risk from Toxic Exposure

• Main Discovery: A single maternal exposure to a toxic fungicide during pregnancy increases the risk of disease and inherited health problems across 20 subsequent generations through stable alterations in reproductive cells.
• Methodology: Researchers monitored 20 generations of rats following an initial gestating female's exposure to a conservative dose of the agricultural fungicide vinclozolin to track the persistence of transgenerational health effects in the kidneys, prostates, testes, and ovaries.
• Key Data: Baseline disease prevalence persisted steadily until the 15th generation, after which the 16th through 18th generations exhibited a prominent spike in disease severity, including lethal pathologies resulting in the death of mothers or entire litters during the birth process.
• Significance: The findings indicate that current rising rates of chronic conditions may be deeply rooted in ancestral exposure to environmental toxins, as programmed epigenetic changes in the germline become as stable as permanent genetic mutations.
• Future Application: The identification of measurable epigenetic biomarkers could predict susceptibility to specific conditions decades before symptoms appear, facilitating a major medical shift from reactionary treatments to targeted preventative care.
• Branch of Science: Epigenetics, Toxicology, and Reproductive Biology.

11 genetic variants affect gut microbiome

A major international study has identified 11 genetic variants that actively shape the human gut microbiome. By regulating the intestinal molecular environment, these genes influence bacterial composition and impact risks for cardiovascular disease and gluten intolerance.
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Scientific Frontline: Extended "At a Glance" Summary

The Core Concept: A comprehensive international study has identified 11 specific regions in the human genome that directly influence the composition and function of the gut microbiome. This research demonstrates that host genetics play a significant, specific role in determining which bacteria inhabit the intestines and how they operate.

Key Distinction/Mechanism: Unlike previous research, which had only confirmed two genetic regions linked to the microbiome, this study expands the known associations to 11 loci. The underlying mechanisms involve specific biological processes, such as determining which molecules appear on the surface of gut cells to serve as food for bacteria and regulating how the gut reacts to bacterial byproducts.

Origin/History: The findings were announced on February 16, 2026, following the publication of two coordinated studies in Nature Genetics led by researchers from Uppsala University, the University of Gothenburg, and the Norwegian University of Science and Technology (NTNU).

Major Frameworks/Components:

• Genome-Wide Association Analysis: Utilized data from over 28,000 individuals to map genetic variants to microbiome composition.
• Biobank Integration: Leveraged massive datasets from Swedish (SCAPIS, MOS, SIMPLER) and Norwegian (HUNT) population studies.
• Host-Microbe Interaction: Focused on genes affecting nutrient absorption and the intestinal molecular environment.

Diagnosis of cardiomyopathy is on the rise

Daniel Lindholm, cardiologist, researcher at the Department of Medical Sciences.
Photo Credit: Daniel Lindholm

Scientific Frontline: "At a Glance" Summary

• Main Discovery: A comprehensive longitudinal study reveals that the number of patients diagnosed with cardiomyopathy in Sweden has more than doubled over the past two decades, with these conditions linked to substantial excess mortality.
• Methodology: Researchers mapped all adult cardiomyopathy cases in Sweden from 2004 to 2023 using the National Board of Health and Welfare’s health registers, comprising 57,000 patients, and compared survival rates against the Human Mortality Database.
• Key Data: Mortality rates among the youngest patients were 32 times higher for women and 16 times higher for men compared to the general population, while mortality remained double the average even among the oldest patient cohorts.
• Significance: The results highlight a critical need for earlier detection and better management strategies, particularly given the disproportionately high relative mortality risk observed in younger women compared to their male counterparts.
• Future Application: These findings provide the epidemiological foundation required to refine diagnostic guidelines and develop targeted treatments aimed at reducing the high mortality associated with heart muscle diseases.
• Branch of Science: Cardiology and Epidemiology
• Additional Detail: The specific increase in diagnoses among women is notably driven by a rise in identified cases of Takotsubo cardiomyopathy, also known as stress-induced cardiomyopathy or broken heart syndrome.

Epidemiology: In-Depth Description

Epidemiology is the fundamental science of public health, defined as the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to the control of health problems. Its primary goals are to identify the etiology (cause) of diseases, determine the extent of disease burden in communities, study the natural history and prognosis of diseases, and evaluate preventive and therapeutic measures.

Childhood lead exposure associated with increased depressive symptoms in adolescence

Childhood blood lead concentrations with increased depressive symptoms in adolescence, with larger increases when exposure occurred later in childhood.
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Scientific Frontline: "At a Glance" Summary

• Main Discovery: Higher concentrations of lead in blood throughout childhood are linked to increased depressive symptoms in adolescence, with exposure at age 8 showing a particularly strong association with symptom onset and severity.
• Methodology: Researchers analyzed data from 218 caregiver-child pairs in the Health Outcomes and Measures of Environment Study, measuring blood lead concentrations at ages 1, 2, 3, 4, 5, 8, and 12, and assessing anxiety and depression symptoms at approximately age 12.
• Key Data: Each doubling in mean childhood blood lead concentrations was significantly associated with an increased risk of elevated child-reported depressive symptoms.
• Significance: This study fills a critical gap by connecting low-level lead exposure—often from environmental sources like dust and aging pipes—directly to the prevalence of psychiatric conditions in U.S. adolescents, rather than just cognitive or behavioral issues.
• Future Application: Public health efforts must expand to prevent cumulative lead exposure and specifically target reduction strategies for older children, not just toddlers, to mitigate long-term mental health risks.
• Branch of Science: Epidemiology and Environmental Health
• Additional Detail: Proposed biological mechanisms for this link include altered neurotransmitter function, oxidative stress, and inflammation in brain regions responsible for mood regulation.

Low vitamin D levels shown to raise risk of hospitalization with potentially fatal respiratory tract infections by 33%

Photo Credit: Karyna Panchenko

Scientific Frontline: "At a Glance" Summary

• Main Discovery: Severe vitamin D deficiency significantly increases the likelihood of hospitalization for respiratory tract infections such as bronchitis and pneumonia.
• Methodology: Researchers analyzed NHS data from 36,258 participants within the UK Biobank to correlate vitamin D serum levels with hospitalization rates for respiratory infections.
• Key Data: Individuals with severe deficiency (below 15 nmol/L) were 33% more likely to be hospitalized than those with sufficient levels (at least 75 nmol/L), with a 4% decrease in hospitalization rate observed for every 10 nmol/L increase in vitamin D.
• Significance: The findings provide empirical data supporting the critical role of vitamin D's antibacterial and antiviral properties in preventing severe respiratory illness and potentially reducing strain on healthcare systems.
• Future Application: Public health strategies may prioritize vitamin D supplementation and fortified food consumption during winter months, specifically targeting high-risk demographics like the elderly and ethnic minority communities.
• Branch of Science: Nutritional Epidemiology
• Additional Detail: Lower respiratory tract infections currently rank among the top leading causes of global mortality for adults over 50 years of age.

Old diseases return as settlement pushes into the Amazon rainforest

Yellow fever cases have begun to rise, spilling over the expanding border between the forest and urban areas.
Photo Credit: Thiago Japyassu

Scientific Frontline: "At a Glance" Summary

• Main Discovery: The expansion of human settlements into the Amazon rainforest, specifically the growing interface between urban areas and forests, is the primary driver behind the recent resurgence of human yellow fever spillover cases.
• Methodology: Researchers analyzed yellow fever case records from Brazil (2000–2021), Colombia (2007–2021), and Peru (2016–2021) alongside land-use data from the MapBiomas Project, modeling the relationship between disease rates and geographic metrics such as forest patch size, edge density, and forest-urban adjacency.
• Key Data: A 10% increase in forest-urban adjacency raised the probability of a spillover event by 0.09, equivalent to a 150% increase in the number of spillover events annually; notably, this high-risk borderland is expanding by approximately 13% per year.
• Significance: Proximity between human settlements and forest edges is a significantly stronger predictor of disease spillover than ecological forest fragmentation alone, raising critical concerns that urban transmission cycles—independent of non-human hosts—could reemerge.
• Future Application: Findings indicate a critical need to realign public health infrastructure and vaccination stockpiles to specifically target expanding forest-urban interfaces, rather than relying solely on broad ecological conservation metrics.
• Branch of Science: Disease Ecology and Epidemiology
• Additional Detail: Recent data highlights the urgency, with confirmed yellow fever cases in 2025 showing a threefold increase compared to 2024 and shifting geographically to areas outside the Amazon basin.

Bat-Borne Sarbecoviruses Spilled Over in Southeast Asia Pre-Pandemic

Elephant loggers bring in a timber harvest in Myanmar.
Photo Credit: Tierra Smiley Evans/UC Davis

Scientific Frontline: "At a Glance" Summary: Bat-Borne Sarbecoviruses Spilled Over in Southeast Asia Pre-Pandemic

• Main Discovery: A virus previously found exclusively in bats was detected in the antibodies of human populations in rural Myanmar, demonstrating that exposure to diverse sarbecoviruses, including strains closely related to SARS-CoV-2, occurred prior to the pandemic.
• Methodology: Researchers collaborated with local clinics to screen nearly 700 rural and urban residents for sarbecoviruses between July 2017 and February 2020. The surveillance relied entirely on human patient sampling, targeting individuals seeking medical treatment and healthy populations near elephant logging camps, without collecting direct wildlife samples.
• Key Data: Blood screenings revealed that 12 percent of the study participants possessed antibodies indicating past exposure to a sarbecovirus, though no active infections were found. Exposure was exclusively identified in rural residents, particularly those working in logging, hunting, or bat guano harvesting, which put them in direct proximity to bats.
• Significance: The results yield concrete epidemiologic and immunologic evidence that zoonotic spillover of bat-borne coronaviruses is actively occurring. The data strongly suggests that human intrusion into newly disturbed, biodiverse environments substantially elevates the risk of wildlife-to-human viral transmission.
• Future Application: The findings establish a baseline for developing targeted mitigation strategies and underscore the necessity of continuous viral surveillance at the human-wildlife interface in Southeast Asia. This reconnaissance approach will be utilized to predict and potentially intercept the future emergence of novel zoonotic diseases.
• Branch of Science: Virology, Epidemiology

Alcohol consumption increases the risks of over 60 diseases

Photo Credit: Taylor Friehl

Alcohol consumption increases the risks of over 60 diseases in Chinese men, including many diseases not previously linked to alcohol, according to a new study by researchers from Oxford Population Health and Peking University, published in Nature Medicine.

Alcohol consumption is estimated to be responsible for about 3 million deaths worldwide each year, and it is increasing in many low- and middle-income countries such as China. The harmful effects of heavy drinking for certain diseases (such as liver cirrhosis, stroke and several types of cancer) are well known, but very few studies have systematically assessed the impact of alcohol use on an extensive range of diseases within the same population.

The study shows that alcohol use increases the risks of 61 diseases in men in China, including many non-fatal diseases not known to be alcohol-related due to limited previous evidence. The findings of this study demonstrate the influence that alcohol intake may have on the risk of disease in populations around the world.

The researchers used data from the China Kadoorie Biobank (CKB), a collaborative study of over 512,000 adults recruited during 2004-08 from ten diverse urban and rural areas across China. Study participants were interviewed about their lifestyle and behaviors, including detailed alcohol drinking patterns. About a third of men, but only 2% of women, drank alcohol regularly (ie at least once a week). The researchers comprehensively assessed the health effects of alcohol use on over 200 different diseases in men identified through linkage to hospital records over a period of about 12 years. Importantly, they also undertook a genetic analysis to clarify whether or not alcohol intake was responsible for causing disease.

Exposure to “forever chemicals” during pregnancy linked to increased risk of obesity in kids

Toxic "forever chemicals" are used in oil- and water-repellant textiles, personal care products, firefighting foams, food packaging, medical products and many other household products.
Photo Credit: Stijn Dijkstra

A federally funded study led by researchers at Brown University showed links between prenatal exposure to per- and polyfluoroalkyl substances and slightly higher body mass indices in children.

The risks of exposure to “forever chemicals” start even before birth, a new study confirms, potentially setting up children for future health issues.

Exposure to per- and polyfluoroalkyl substances (PFAS) during pregnancy was linked to slightly higher body mass indices and an increased risk of obesity in children, according to a new Environmental Health Perspectives study led by Brown University researchers.

While this link has been suggested in previous research, the data has been inconclusive. The new study, which was funded by the Environmental Influences on Child Health Outcomes program at the National Institutes of Health, involves a much broader data set with research sites across the country, said lead author Yun “Jamie” Liu, a postdoctoral research associate in epidemiology at the Brown University School of Public Health.

“The findings were based on eight research cohorts located in different parts of the U.S. as well as with different demographics,” Liu said. “This makes our study findings more generalizable to the population as a whole.”

Can Artificial Intelligence Predict Spatiotemporal Distribution of Dengue Fever Outbreaks with Remote Sensing Data?

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Researchers train machine learning model with climatic and epidemiology remote sensing data to predict the spatiotemporal distribution of disease outbreaks

Cases of dengue fever and other zoonotic diseases will keep increasing owing to climate change, and prevention via early warning is one of our best options against them. Recently, researchers combined a machine learning model with remote sensing climatic data and information on past dengue fever cases in Chinese Taiwan, with the aim of predicting likely outbreak locations. Their findings highlight the hurdles to this approach and could facilitate more accurate predictive models.

Outbreaks of zoonotic diseases, which are those transmitted from animals to humans, are globally on the rise owing to climate change. In particular, the spread of diseases transmitted by mosquitoes is very sensitive to climate change, and Chinese Taiwan has seen a worrisome increase in the number of cases of dengue fever in recent years.

Like for most known diseases, the popular saying “an ounce of prevention is worth a pound of cure” also rings true for dengue fever. Since there is still no safe and effective vaccine for all on a global scale, dengue fever prevention efforts rely on limiting places where mosquitoes can lay their eggs and giving people an early warning when an outbreak is likely to happen. However, thus far, there are no mathematical models that can accurately predict the location of dengue fever outbreaks ahead of time.

Using sewage to forecast COVID-19 infections

Collecting samples at a wastewater treatment plant for the study
Photo Credit: provided by Masaaki Kitajima

Sifting through sewage for SARS-CoV-2 genetic material could help authorities tailor infection control policies.

A new mathematical model uses wastewater samples to effectively forecast the number of clinical COVID-19 cases in a community five days in advance. The approach was developed and validated by Hokkaido University environmental engineer, Masaaki Kitajima, and colleagues in Japan. It could help healthcare authorities better tailor infection control policies, especially when clinical surveillance is lacking. The researchers reported their findings in the journal Environment International. 

Testing wastewater samples for SARS-CoV-2 as a means to predict surges in clinical cases has been attracting attention. Scientists have been researching this approach since the beginning of the pandemic. However, current methods aren’t particularly sensitive and can only detect increasing cases without being able to forecast their numbers within a community.

Kitajima and his colleagues had already developed a method to detect SARS-CoV-2 RNA in wastewater samples. But this method requires solid material and does not work well with diluted wastewater on rainy days or with treated wastewater that has been clarified and is mostly liquid. So, they modified their approach. Instead of using low-speed centrifugation to create pellets from wastewater samples that then go on to be tested, they used special filters that can capture the viral RNA from diluted wastewater. This is followed by extracting RNA from the filter, amplifying it, and then running polymerase chain reaction (PCR) tests to detect it. They call the new method Efficient and Practical Virus Identification System with Enhanced Sensitivity for Membrane (EPISENS-M).

Nicotine exposure during pregnancy may increase risk of sudden infant death

SNUS
Photo Credit: Bengt Wiberg

Infants whose mothers have used snus (a moist oral tobacco product) during pregnancy run three times the risk of sudden infant death, according to a comprehensive registry study from Karolinska Institutet published in the journal Pediatric Research. The risk was much lower if the mother had stopped taking snus before the first antenatal visit. The researchers conclude that all types of nicotine products should be avoided during pregnancy.

“Fortunately, the incidence of sudden infant death is very low, but we can see that taking snus or smoking while pregnant is associated with an increased risk,” says Anna Gunnerbeck, pediatrician at the Astrid Lindgren Children’s Hospital and researcher at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet.

Studied two million babies

While it is known that smoking during pregnancy is a risk factor in sudden infant death, little research has been done on snus and other nicotine products. To address this, the researchers conducted a registry study comprising over two million babies born in Sweden between 1999 and 2019. During this time, only two out of 10,000 babies suffered sudden infant death, which is when death occurs suddenly for no apparent reason during sleep.