Angelica P. Ahrens, University of Florida; Eric W. Triplett, University of Florida, and Johnny Ludvigsson, Linköping University

Early screening for neurodevelopmental disorders such as autism is important to ensure children have the support they need to gain the essential skills for daily life. The American Academy of Pediatrics recommends that all children be screened for developmental delays, with additional screening for those who are preterm or have a low birth weight.

However, the U.S. Preventive Services Task Force has called for more research into the effectiveness of current autism screening practices. Primarily based on milestone checklists and symptoms, autism diagnoses also currently rely on observations of behavior that often manifests after crucial developmental stages have passed.

Researchers and clinicians are working to develop simple, reliable tools that could identify early signs or risk factors of a condition before symptoms are obvious. While early screening can lead to the risk of overdiagnosis, understanding a child’s developmental needs can help guide families toward resources that address those needs sooner.

We are researchers who study the role the microbiome plays in a variety of conditions, such as mental illness, autoimmunity, obesity, preterm birth and others. In our recently published research on Swedish children, we found that microbes and the metabolites they produce in the guts of infants – both found in poop and cord blood – could help screen for a child’s risk of neurodevelopmental conditions such as autism. And these differences can be detected as early as birth or within the first year of life. These markers were evident, on average, over a decade before the children were diagnosed.

Microbes as biomarkers

Biomarkers are biological indicators – such as genes, proteins or metabolites in blood, stool or other types of samples – that signal the presence of a condition at a certain point in time. There are no known biomarkers for autism. Efforts to find biomarkers have been largely hindered by the fact that autism has many potential pathways that lead to it, and researchers tend to ignore how these causes may work together as a whole.

One potential biomarker for neurodevelopmental conditions such as autism are gut microbes. The connection between the gut and brain, or the gut-brain axis, is an area of considerable interest among scientists. Gut microbes play significant roles in health, including in immunity, neurotransmitter balance, digestive health and much more.

A lot of work has been done around mapping what a “typical” microbiome looks like based on age and organ system. Researchers have shown that the microbiome is personalized enough that it can distinguish two people or two households even better than genetics, with differences in colonization starting very early in life.

The microbiome undergoes immense changes during childhood. It shapes and is shaped by the immune system and influenced by life changes and events. It is also influenced by factors like genetics, environment, lifestyle, infection and medications.

Gastrointestinal symptoms such as diarrhea, pain and constipation are common in children with autism and ADHD, with as many as 30% to 70% of autism patients also diagnosed with functional gastrointestinal disorders. Untreated GI issues can also lead to additional sleep and behavioral disorders among these children. A small pilot study found that children with autism showed improvements in gastrointestinal and autism-related symptoms after having healthy microbes transferred into their guts, with some benefits lasting up to two years.

Most studies on the microbiome and neurodevelopmental conditions, however, are restricted to people who are already diagnosed with ADHD, autism or other conditions, and these studies often show mixed results. These limitations raise an important question: Does the microbiome play a direct role in the development of autism and other neurodevelopmental conditions, or are changes in microbiome composition a consequence of the conditions themselves?

Some investigations have proposed that the microbiome has little or no association with future autism. However, these studies have a notable limitation: They don’t examine microbial imbalances prior to diagnosis or symptom onset. Instead, these studies focus on children already diagnosed with autism, comparing them to their siblings and unrelated neurotypical children. In most cases, dietary data and samples are collected several years after diagnosis, meaning the study cannot test for whether microbial imbalances cause autism.

Microbes matter

We wondered whether studying the bacteria residing in small children before they are diagnosed or show symptoms of autism or other conditions could give us a clue into their neurodevelopment. So, we examined the cord blood and stool collected at approximately 1 year of age from participants of an ongoing study called All Babies in Southeast Sweden, which follows the health of approximately 17,000 children born between 1997 and 1999 and their parents. We have followed these children since birth, nearly 1,200 of whom were later diagnosed with a neurodevelopmental disorder by age 23.

We found significant differences in bacterial composition and metabolite levels that developed before symptoms of neurodevelopmental conditions – such as gastrointestinal upset, crankiness and sleep problems – as well as formal medical diagnoses. These differences spanned many conditions, including autism, ADHD and speech disorders.

Next, we linked bacteria to neurotransmitters – chemical signals that help brain cells communicate – and vitamins such as riboflavin and vitamin B in the child’s stool. Given previous research on children and adults already diagnosed with a neurodevelopmental disorder, we expected to find differences in the microbiome composition and health between those with and without neurodevelopmental conditions.

But we were surprised to discover just how early these differences emerge. We saw variability in the microbes and metabolites that affect immune and brain health, among others, in the stool collected from the diapers of children around 1 year of age and in umbilical cord blood collected at birth.

The imbalance in microbial composition – what microbiologists call dysbiosis – we observed suggests that incomplete recovery from repeated antibiotic use may greatly affect children during this vulnerable period. Similarly, we saw that repeated ear infections were linked to a twofold increased likelihood of developing autism.

Children who both repeatedly used antibiotics and had microbial imbalances were significantly more likely to develop autism. More specifically, children with an absence of Coprococcus comes, a bacterium linked to mental health and quality of life, and increased prevalence of Citrobacter, a bacterium known for antimicrobial resistance, along with repeated antibiotic use were two to four times more likely to develop a neurodevelopmental disorder.

Antibiotics are necessary for treating certain bacterial infections in children, and we emphasize that our findings do not suggest avoiding their use altogether. Parents should use antibiotics if they are prescribed and deemed necessary by their pediatrician. Rather, our study suggests that repeated antibiotic use during early childhood may signal underlying immune dysfunction or disrupted brain development, which can be influenced by the gut microbiome. In any case, it is important to consider whether children could benefit from treatments to restore their gut microbes after taking antibiotics, an area we are actively studying.

Another microbial imbalance in children who later were diagnosed with neurodevelopmental disorders was a decrease in Akkermansia muciniphila, a bacterium that reinforces the lining of the gut and is linked to neurotransmitters important to neurological health.

Even after we accounted for factors that could influence gut microbe composition, such as how the baby was delivered and breastfeeding, the relationship between imbalanced bacteria and future diagnosis persisted. And these imbalances preceded diagnosis of autism, ADHD or intellectual disability by 13 to 14 years on average, refuting the assumption that gut microbe imbalances arise from diet.

We found that lipids and bile acids were depleted in the cord blood of newborns with future autism. These compounds provide nutrients for beneficial bacteria, help maintain immune balance and influence neurotransmitter systems and signaling pathways in the brain.

Microbiome screening at well-child visits

Microbiome screening is not a common practice in well-child visits. But our findings suggest that detecting imbalances in beneficial and harmful bacteria, especially during critical periods of early childhood development, can provide essential insights for clinicians and families.

There is a long way to go before such screening becomes a standard part of pediatric care. Researchers still need validated methods to analyze and interpret microbiome data in the clinic. It’s also unclear how bacterial differences change across time in children around the world – not just which bacteria are present or absent, but also how they may be shaping immune responses and metabolism. But our findings reaffirm the growing body of evidence that the early gut microbiome plays a key role in shaping neurodevelopment.

Angelica P. Ahrens, Assistant Research Scientist in Data Science and Microbiology, University of Florida; Eric W. Triplett, Professor and Chair of Microbiology and Cell Science, University of Florida, and Johnny Ludvigsson, Professor Emeritus of Biomedical and Clinical Sciences, Linköping University

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

Jennifer Horney, University of Delaware

Hurricane Helene’s flooding has subsided, but health risks are growing in hard-hit regions of the North Carolina mountains, where many people lost access to power and clean water.

More than 150 deaths across the Southeast had been attributed to Hurricane Helene within days of the late September 2024 storm, according to The Associated Press, and hundreds of people remained unaccounted for. In many areas hit by flooding, homes were left isolated by damaged roads and bridges. Phone service was down. And electricity was likely to be out for weeks.

As a disaster epidemiologist and a native North Carolinian, I have been hearing stories from the region that are devastating. Contaminated water is one of the leading health risks, but residents also face harm to mental health, stress that exacerbates chronic diseases and several other threats.

Water risks: What you can’t see can hurt you

Access to clean water is one of the most urgent health concerns after a flood. People need water for drinking, preparing food, cleaning, bathing, even flushing toilets. Contact with contaminated water can cause serious illnesses.

Floodwater with sewage or other harmful contaminants in it can lead to infectious diseases, particularly among people who are already ill, immunocompromised or have open wounds. Even after the water recedes, residents may underestimate the potential for contamination by unseen bacteria such as fecal coliform, heavy metals such as lead, and organic and inorganic contaminants such as pesticides.

In Asheville, the flooding caused so much damage to water treatment facilities and pipes that officials warned the city could be without running water for potentially weeks. Most private wells also require electricity to pump and filter the water, and many people in surrounding areas could be without power for weeks.

State and federal agencies began delivering extra bottled water to the region shortly after the storm, but supplies were limited, and it’s likely that a number of people won’t be able to reach the distribution sites soon. Access to fresh food is another concern for many areas with roads and bridges washed out.

Inside homes, floodwater can create more health risks, particularly if mold grows on wet fabrics and wallboard. Standing water outside also increases the risk of exposure to mosquitoes carrying diseases such as West Nile virus. Mosquitoes are still active in much of the region in the fall.

Inundation, isolation and access to health care

Many of the images in the news after the hurricane hit showed roads, hospitals and entire towns inundated by floodwaters. In North Carolina, more than 400 roads were closed, blocking access to the major regional health care hub of Asheville, as well as many smaller communities.

While supplies can be airlifted to clinics, residents needing urgent access to treatments such as dialysis or daily medications for substance use disorders may have been cut off. Health care workers may be unable to access their clinics as well.

Cuts and other injuries are common in the aftermath of storms, as people clean up debris, and even small wounds can become infected. The stress, exertion and exposure to heat can also exacerbate chronic conditions such as cardiovascular and respiratory diseases.

Mental health and long-term effects

Beyond the risks to physical health, the fear, stress and losses can affect mental health.

Research has consistently shown that emergency responders’ mental health can suffer in widespread disasters, particularly when they know disaster victims, deal with severe injuries or feel helpless. All of those conditions were present as Hurricane Helene’s floodwaters swept away dozens of people, with many more still listed as missing.

Stigma, cost and a lack of mental health care providers all add to the ongoing challenges to mental health after disasters. Research shows that a large percentage of people face mental health challenges after disasters.

According to the Substance Abuse and Mental Health Services Administration, two federal grant programs provide mental health services support to individuals and communities after disasters. However, one of those sources of funding ends after 60 days, the other after one year. Given the decades of recovery facing western North Carolina after Hurricane Helene, I believe these programs are woefully inadequate to meet the mental health needs of the populations affected by the storm.

Flooded regions will need long-term help

Western North Carolina is often described as a “climate refuge” because of its cooler summers. And Asheville in particular has become a popular place for retirees and new residents. Recent data shows the city has the second highest migration rate in the nation.

But Helene and other extreme storms that have flooded the region make its vulnerabilities clear.

In the aftermath of the flooding, newcomers unfamiliar with the risks and longtime residents alike will be dealing with ongoing health concerns as they try to clean up and rebuild from the storm. Even as attention shifts to other disasters, the people in this region will still need help to recover for months and years to come.

Jennifer Horney, Professor of Epidemiology and Core Faculty of Disaster Research Center, University of Delaware

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

Alan Veliz-Cuba, University of Dayton

You can probably think of a time when you’ve used math to solve an everyday problem, such as calculating a tip at a restaurant or determining the square footage of a room. But what role does math play in solving complex problems such as curing a disease?

In my job as an applied mathematician, I use mathematical tools to study and solve complex problems in biology. I have worked on problems involving gene and neural networks such as interactions between cells and decision-making. To do this, I create descriptions of a real-world situation in mathematical language. The act of turning a situation into a mathematical representation is called modeling.

Translating real situations into mathematical terms

If you ever solved an arithmetic problem about the speed of trains or cost of groceries, that’s an example of mathematical modeling. But for more difficult questions, even just writing the real-world scenario as a math problem can be complicated. This process requires a lot of creativity and understanding of the problem at hand and is often the result of applied mathematicians working with scientists in other disciplines.

As an example, we could represent a game of Sudoku as a mathematical model. In Sudoku, the player fills empty boxes in a puzzle with numbers between 1 and 9 subject to some rules, such as no repeated numbers in any row or column.

The puzzle begins with some prefilled boxes, and the goal is to figure out which numbers go in the rest of the boxes.

Imagine that a variable, say x, represents the number that goes in one of those empty boxes. We can guarantee that x is between 1 and 9 by saying that x solves the equation (x-1)(x-2) … (x-9)=0. This equation is true only when one of the factors on the left side is zero. Each of the factors on the left side is zero only when x is a number between 1 and 9; for example, (x-1)=0 when x=1. This equation encodes a fact about our game of Sudoku, and we can encode the other features of the game similarly. The resulting model of Sudoku will be a set of equations with 81 variables, one for each box in the puzzle.

Another situation we might model is the concentration of a drug, say aspirin, in a person’s bloodstream. In this case, we would be interested in how the concentration changes as we ingest aspirin and the body metabolizes it. Just like with Sudoku, one can create a set of equations that describe how the concentration of aspirin evolves over time and how additional ingestion affects the dynamics of this medication. In contrast to Sudoku, however, the variables that represent concentrations are not static but rather change over time.

But the act of modeling is not always so straightforward. How would we model diseases such as cancer? Is it enough to model the size and shape of a tumor, or do we need to model every single blood vessel inside the tumor? Every single cell? Every single chemical in each cell? There is much that is unknown about cancer, so how can we model such unknown features? Is it even possible?

Applied mathematicians have to find a balance between models that are realistic enough to be useful and simple enough to be implemented. Building these models may take several years, but in collaboration with experimental scientists, the act of trying to find a model often provides novel insight into the real-world problem.

Mathematical models help find real solutions

After writing a mathematical problem to represent a situation, the second step in the modeling process is to solve the problem.

For Sudoku, we need to solve a collection of equations with 81 variables. For the aspirin example, we need to solve an equation that describes the rate of change of concentrations. This is where all the math that has been and is still being invented comes into play. Areas of pure math such as algebra, analysis, combinatorics and many others can be used – in some cases combined – to solve the complex math problems arising from applications of math to the real world.

The third step of the modeling process consists of translating the mathematical solution into the solution to the applied problem. In the case of Sudoku, the solution to the equations tells us which number should go in each box to solve the puzzle. In the case of aspirin, the solution would be a set of curves that tell us the aspirin concentration in the digestive system and bloodstream. This is how applied mathematics works.

When creating a model isn’t enough

Or is it? While this three-step process is the ideal process of applied math, reality is more complicated. Once I reach the second step where I want the solution of the math problem, very often, if not most of the time, it turns out that no one knows how to solve the math problem in the model. In some cases, the math to study the problem doesn’t even exist.

For example, it is difficult to analyze models of cancer because the interactions between genes, proteins and chemicals are not as straightforward as the relationships between boxes in a game of Sudoku. The main difficulty is that these interactions are “nonlinear,” meaning that the effect of two inputs is not simply the sum of the individual effects. To address this, I have been working on novel ways to study nonlinear systems, such as Boolean network theory and polynomial algebra. With this and traditional approaches, my colleagues and I have studied questions in areas such as
decision-making,
gene networks,
cellular differentiation and
limb regeneration.

When approaching unsolved applied math problems, the distinction between applied and pure mathematics often vanishes. Areas that were considered at one time too abstract have been exactly what is needed for modern problems. This highlights the importance of math for all of us; current areas of pure mathematics can become the applied mathematics of tomorrow and be the tools needed for complex, real-world problems.

Alan Veliz-Cuba, Associate Professor of Mathematics, University of Dayton

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