(Press-News.org) It is not only premature babies and children with underlying diseases who suffer from serious respiratory syncytial virus (RSV) infections. Even healthy, full-term babies are at significant risk of intensive care or prolonged hospitalisation – especially during the first three months of life. This is according to a comprehensive registry study from Karolinska Institutet in Sweden published in The Lancet Regional Health – Europe.
RSV is a common cause of respiratory infections in young children and accounts for around 245,000 hospital admissions annually in Europe. Researchers have now analysed data from over 2.3 million children born in Sweden between 2001 and 2022 to find out who is at greatest risk of suffering serious complications or dying from an RSV infection.
Preventive treatment available
It is well-known that premature babies and children with chronic diseases are at increased risk of developing severe illness when infected with RSV. It is also known that children under three months of age are particularly vulnerable, but it has not been entirely clear how common severe disease is among previously healthy children. The study shows that the largest group among the children who needed intensive care or were hospitalised for a long period of time were under three months of age, previously healthy and born at full term.
“When shaping treatment strategies, it is important to take into account that even healthy infants can be severely affected by RSV,” says the study’s first author, Giulia Dallagiacoma, a physician and doctoral student at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet. “The good news is that there is now preventive treatment that can be given to newborns, and a vaccine that can be given to pregnant women.”
Starting September 10, 2025, all newborns in Sweden will be offered preventive treatment with antibodies during the RSV season. The drug works much like a vaccine and protects against severe RSV infection for about six months.
Several risk factors identified
A total of 1.7 per cent of the children in the study were diagnosed with RSV infection. Among those, just under 12 per cent (4,621 children) had a severe course of illness. The median age of children who needed intensive care was just under two months, and the majority of them had no underlying disease.
The researchers identified several factors that were linked to an increased risk of needing intensive care or dying. Children who were born in the winter, or had siblings aged 0–3 years or a twin, had approximately a threefold increased risk, while children who were small at birth had an almost fourfold increased risk. Children with underlying medical conditions had more than a fourfold increased risk of severe illness or death.
“We know that several underlying diseases increase the risk of severe RSV infection, and it is these children who have so far been targeted for protection with the preventive treatment that has been available,” says the study’s last author, Samuel Rhedin, resident physician at Sachs’ Children and Youth Hospital and associate professor at the Department of Medical Epidemiology and Biostatistics, Karolinska Institutet. “However, the study highlights that a large proportion of children who require intensive care due to their RSV infection were previously healthy. Now that better preventive medicines are available, it is therefore positive that the definition of risk groups is being broadened to offer protection during the RSV season to previously healthy infants as well.”
The study was conducted in collaboration with researchers at the University of Helsinki and Helsinki University Hospital in Finland. It was funded by Karolinska Institutet, the Swedish Research Council, the Swedish Heart-Lung Foundation, the Swedish Asthma and Allergy Association’s research fund and Region Stockholm, among others. Some of the researchers have received consulting fees from pharmaceutical companies, but these are unrelated to the current study. See the scientific article for more information about potential conflicts of interest.
Publication: “Risk factors for severe outcomes of respiratory syncytial virus infection in children: a nationwide cohort study in Sweden”, Giulia Dallagiacoma, Cecilia Lundholm, Awad I Smew, Emma Caffrey Osvald, Pekka Vartiainen, Santtu Heinonen, Tobias Alfvén, Catarina Almqvist, Samuel Rhedin, The Lancet Regional Health – Europe, online 10 September 2025, doi: 10.1016/j.lanepe.2025.101447.
END
Even healthy children can be severely affected by RSV
2025-09-10
ELSE PRESS RELEASES FROM THIS DATE:
Keto diet linked to reduced depression symptoms in college students
2025-09-10
[Embargoed until 8 p.m. ET Sept. 9, 2025 (1 a.m. UK Sept. 10, 2025), coinciding with publication in Translational Psychiatry]
COLUMBUS, Ohio – A new study shows an association between at least 10 weeks of following a well-formulated ketogenic diet and a roughly 70% decrease in depression symptoms among a small group of college students.
Beyond the reduction in self-reported and clinician rated depression, the students’ global well-being increased nearly three-fold and their performance improved on several cognitive tasks. All but one participant ...
Blood test identifies HPV-associated head and neck cancers up to 10 years before symptoms
2025-09-10
Human papilloma virus (HPV) causes around 70% of head and neck cancers in the United States, making it the most common cancer caused by the virus, with rates increasing each year. Unlike cervical cancers caused by HPV, there is no screening test for HPV-associated head and neck cancers. This means that patients are usually diagnosed after a tumor has grown to billions of cells in size, causing symptoms and spreading to lymph nodes. Screening methods that can detect these cancers much earlier could mean earlier treatment interventions for patients.
In a new federally funded study, published in the Journal of the National Cancer Institute, Mass General Brigham researchers ...
Odds of dementia strongly linked to number of co-existing mental health disorders
2025-09-09
The odds of developing dementia are strongly linked to the number of co-existing mental health disorders, rising from twice as high for one disorder to 11 times as high for four or more, finds research published in the open access journal BMJ Mental Health.
In particular, the combination of concurrent mood and anxiety disorders is linked to odds of dementia of up to 90%, the findings indicate.
Psychiatric disorders, such as depression, anxiety, and bipolar disorder, have been individually associated with an increased risk ...
Large social and economic inequalities persist among UK doctors
2025-09-09
Large social and economic inequalities persist among UK doctors, with those from a professional background 6 times more likely to become a medical practitioner than those from a working class background, reveals a 10 year study, published in the open access journal BMJ Open.
Greater efforts are needed to boost the social mobility of medical school applicants and better understand the effects of these inequalities on patient care, say the researchers.
National data from 2014 show that only 4% of practising doctors came from lower-income working class backgrounds. And despite concerted efforts over the past 20 years to ...
Research reveals how microplastics threaten Gulf of Mexico marine life
2025-09-09
Critical wildlife habitats are exposed to pollution risk in the seas off the southern United States, with implications for human health and food security. “Most of the pollution comes from rivers and not from wastewater treatment plants,” says CMCC scientist Annalisa Bracco, co-author of the study that used advanced computer models to track tiny plastic particles across three years.
The Gulf of Mexico is facing a growing threat from microplastic pollution, with new research revealing how tiny plastic particles are accumulating in areas crucial to marine life including sea turtles, red snapper, and dolphins. A comprehensive study ...
AI tool developed at Oxford helps astronomers find supernovae in a sky full of noise
2025-09-09
A new AI-powered tool has reduced astronomers’ workload by 85% - filtering through thousands of data alerts to identify the few genuine signals caused by supernovae (powerful explosions from dying stars). The findings have been published today (10 Sept) in The Astrophysical Journal.
Lead researcher Dr Héloïse Stevance (Department of Physics, University of Oxford) said: “The surprising thing is how little data it took. With just 15,000 examples and the computing power of my laptop, I could train smart algorithms to do the heavy lifting and automate what used to take a human beings hours to do each day. This demonstrates that ...
Hungry star is eating its cosmic twin at rate never seen before
2025-09-09
A greedy white dwarf star not far from Earth is devouring its closest celestial companion at a rate never seen before, space scientists have discovered.
Their study found the double star, named V Sagittae, is burning unusually bright as the super-dense white dwarf is gorging on its larger twin in a feeding frenzy.
Experts think the stars are locked in an extraterrestrial tango as they orbit each other every 12.3 hours, gradually pulling each other closer.
They say it could cause a massive explosion so bright it would be seen by the naked eye from Earth, some 10,000 lightyears away.
The findings were made by an international team of astronomers involving Professor Phil Charles from University ...
The Age of Feasting: Late Bronze Age networks developed through massive food festivals, with animals brought from far and wide
2025-09-09
Middens, massive prehistoric rubbish heaps which became part of the British landscape, are revealing the distances people travelled to feast together at the end of the Bronze Age.
In the largest study of its kind, archaeologists from Cardiff University used cutting-edge isotope analysis on material found within six middens in Wiltshire and the Thames Valley.
The results, which reveal where the animals that were feasted on were raised, shed light on the catchment of these vast feasts, arguably the largest to take place in Britain ...
Study of breast cell changes in motherhood provides clues to breastfeeding difficulties
2025-09-09
In a study in mice, researchers have identified genes associated with the dramatic transformation of the mammary gland in pregnancy, breastfeeding, and after breastfeeding as it returns to its resting state.
Their results form the most detailed atlas of genetic expression ever produced for the adult developmental cycle of the mammary gland. They are published today in the journal Nucleic Acids Research.
The mammary gland is made up of different cell types, each with a different function - such as fat cells that provide structural support, and basal cells that are crucial for milk ejection.
The ...
Seizure spread marks loss of consciousness
2025-09-09
Seizure spread marks loss of consciousness
Loss of consciousness can pose real dangers for people with seizure disorders. And while not all seizures cause loss of consciousness, Yale researchers have now discovered how one common type of seizures do.
Frontal lobe seizures are classified as “focal” seizures, a subtype in which the problematic activity generates in a single region of the brain. In the case of frontal lobe seizures, activity originates in the brain’s frontal lobes, located behind the forehead.
But while some cause loss of consciousness, others don’t.
The reason, researchers found, is that ...