Heatwaves have a major impact on the spread of many diseases — Irish research
New research from scientists in Ireland strongly implies that heatwaves have a major influence on the spread of many diseases.
Specifically, the scientists have discovered that differences in heatwaves — such as how much hotter they are than normal temperatures, and how long they last — can increase disease burden by up to 13 times in a commonly used experimental animal model.
Their discovery and its implications come at an important time, with global climate change and related extreme weather events continuing to impact many in various ways (temperatures approached 50°C in Pakistan last month, while a cold snap in South Africa approached freezing conditions).
Given the increased frequency and intensity of heatwaves in particular, it's crucial to understand how these events will affect the spread of disease.
Daphnia magna (water flea). Picture: Dieter Ebert
While scientists have a relatively good idea of how temperature impacts some viruses and disease-causing pathogens and parasites, they know much less about the effects of sudden heatwaves or cold snaps, or how influential variation in the duration of these events are.
That is what the scientists behind the new research, just published in the leading international journal PLOS Climate, set out to explore.
Niamh McCartan: "While Ireland has so far been less affected, the findings of our study highlight the urgent need to understand how warming and extreme weather events can alter disease dynamics more broadly.'
First author, Niamh McCartan, a PhD candidate from Trinity College Dublin's s School of Natural Sciences, noted:
'From a bigger-picture perspective, this work underlines the need for more detailed, context-specific models to help better predict the likely impact of heatwaves and climate change on different diseases. We now know that amplitude, duration, baseline temperature and the point at which exposure occurs have differing effects in shaping disease outcomes, so overly simplified models may miss critical complexities. For example, other researchers have suggested almost 70% of covid-19 cases in the summer of 2022 could have been avoided if there hadn't been heatwaves around that time — imagine the difference that a better understanding of how heatwaves alter disease dynamics could have made to countless people.'
The results revealed that complex interactions exist between heatwave attributes and baseline temperatures, which in turn drive context-dependent effects on both pathogen prevalence and proliferation.
Perhaps most importantly, when compared to other types of temperature variation (such as cold snaps), heatwaves behave differently — altering parasite burden up to 13-fold, and thus driving significant variation in infection outcomes.
Parasite spore clusters (Ordospora colligata) seen as black dots within the gut of the host, Daphnia magna
Niamh McCartan explained: 'In this study, we worked with the water flea (Daphnia magna) and a microsporidian pathogen (Ordospora colligata), which are a widely used model for environmentally transmitted diseases, to investigate the impacts of different heatwave attributes. We manipulated the amplitude and duration of heatwaves across four average temperatures and four distinct time points at which the hosts were exposed to the pathogen. This approach gave us 64 unique heatwaves for comparison.'
'A recently published study reported that 58% of human pathogenic diseases have been aggravated by climate change, with temperature changes impacting host susceptibility due to altering biological properties such as how our immune systems function, as well as our behaviour."
'Climate change is also causing mosquito species that carry diseases like dengue, Zika, and malaria to be increasingly found in parts of southern and central Europe, including Italy and France, areas that were previously too cool to support them. While Ireland has so far been less affected, the findings of our study highlight the urgent need to understand how warming and extreme weather events can alter disease dynamics more broadly.'
'With all of this in mind, it's important that future disease-specific models must account for fluctuating and extreme temperatures, not just averages.'
In addition to this big-picture perspective, the findings of this work also have more specific, valuable insights for freshwater ecology, given that the water flea plays an important role in freshwater food webs, helping to support numerous other species that use them as a food source. In other cases, when their numbers plummet, algae can take over and negatively impact water quality, which in turn has a suite of negative, knock-on effects.
This work was funded by a Research Ireland (formerly Science Foundation Ireland) Frontiers for the Future award.
Note: Although not all findings transfer directly across species, the animal model used in these experiments shares key features with many real-world disease systems, making it a powerful tool for uncovering general principles about how climate extremes might reshape disease dynamics.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Irish Examiner
3 days ago
- Irish Examiner
Birth experiences: why care is needed before, during, and after giving birth
Ireland is becoming a better place to have a baby. That's according to the Irish Examiner National Women's Health Survey, conducted by Ipsos B&A, in which women who have had multiple births report a gradual improvement in care over time. However, there is still progress to be made. Some 41% of mothers said their first birth was difficult or complicated. Prenatally, 36% found healthcare professionals unwilling to consider alternative approaches to birth. Dissatisfaction was highest with postnatal care. One in three cited problems accessing lactation consultants and breastfeeding supports. Three in 10 feel there was a lack of information about postpartum recovery, and one in four said they didn't get enough advice about looking after their baby. Deirdre Daly, associate professor of midwifery and director of the Centre for Maternity Care Research at Trinity College Dublin. Deirdre Daly, an associate professor of midwifery and director of the Centre for Maternity Care Research at Trinity College Dublin, believes the maternity service lets women down when it doesn't give them adequate postnatal support: 'Mothers need to learn how to keep themselves and their babies healthy and well, They need to be told what is and isn't normal, so they can reach out for help, if needed. That's how they get off to the best possible start.' Tony Fitzpatrick, the Irish Nurses and Midwives Association's (INMO) director of professional services, says that many of the problems within maternity services are caused by a lack of staffing. Tony Fitzpatrick, the Irish Nurses and Midwives Association's (INMO) director of professional services, says that many of the problems within maternity services are caused by a lack of staffing. This lack extends to postnatal care, where the shortage of public health nurses and general nurses results in inadequate care for mothers and babies after they leave hospital. 'With regard to postnatal care, the INMO has highlighted shortfalls in both public-health-nurse and community-registered, general-nurse staffing levels, as well as the numbers of midwives providing care in maternity hospitals,' he says. 'INMO members have reported they are striving to meet basic care needs for newborns and their mothers, but that they are far too stretched to give mothers the level of care they are trained to provide.' What the INMO would like to see, he says, is 'a maternity service that places women, babies, families, and midwives at the centre of care'. Postnatal hubs Efforts are being made to create such a service. Daly sees the network of postnatal hubs that have opened around Ireland as a welcome development. Run by midwives, they currently operate in Cork, Kerry, Carlow-Kilkenny, Sligo, and Portiuncula in Galway. 'Our research shows women often feel invisible in the maternity service, particularly postnatally, when the focus moves from mother to baby,' says Daly. 'These hubs were set up as a pilot project in 2022 as a way of addressing that. For six weeks after birth and longer, if necessary, women can go to midwives with their questions and worries and midwives can identify and treat potential problems before they escalate.' Dr Cliona Murphy, chair of the Institute of Obstetricians and Gynaecologists. Dr Cliona Murphy, chair of the Institute of Obstetricians and Gynaecologists, adds that plans are under way to open an additional eight hubs throughout 2025 and 2026. 'Each will deliver accessible, woman-centred postnatal care to mothers and babies,' she says. 'They will provide multi-disciplinary support in local settings, with services such as breastfeeding support, birth reflections, and debriefing, wound care and more.' There are other positive developments within the maternity service. Instead of a one-size-fits-all approach, women now have three care pathways to choose from, tailored to their individual clinical needs and preferences. There has also been investment in education and training, with clinical practice guidelines being developed in subjects such as care for women using a birthing pool for labour and birth. Chair of the Association for Improvements in Maternity Care Ireland (AIMS), Krysia Lynch, says there is much we could learn from other countries, citing Germany as an example: 'Women there see the same midwife at all their appointments and build up a relationship of trust with them. We would benefit from that continuity of care in Ireland.' She would also like us to emulate the French by including a postnatal pelvic check as standard: 'Women's pelvic health is so important for their general health and quality of life as they age.' The key to increasing women's satisfaction with the care they receive in the maternity system is ensuring that their voices are heard at all stages, according to Daly. 'Some 41% of first-time mothers find birth difficult or complicated,' she says. 'Nobody thinks they should lower their expectations or anticipate complications. Instead, we should aim to exceed their expectations by consulting them and considering their needs prenatally, during birth, and after they have their baby.' More support second time Stephanie Buckley is a 39-year-old mother of two from Tralee. Her oldest is three, and she was well taken care of when she was pregnant with him: 'My appointments and scans were great. I was listened to and cared for at all times.' It was during labour that things started to veer away from what she expected. Buckley's waters broke. Labour started, but then stalled: 'I was induced, and when he still didn't come out, I had to have a C-section.' She hoped for a different outcome with her second child, who is now four months old. 'But it went the same way,' she says. However, there was one big difference between the two experiences: The level of postnatal care: 'After my first baby was born, the midwives were great, but they were so busy they couldn't spend much time with me.' She saw a lactation consultant and appreciated the visit from her public health nurse: 'But I still had questions, particularly in relation to my C-section recovery, and would have liked more follow-up.' She got this with her second baby, because, in the meantime, a HSE-run postnatal hub opened in Tralee. 'It was everything I'd been looking for,' she says. 'At my first visit, I had a full debrief on the birth, was checked for postpartum depression, and the midwife looked at my wound. It was just about to get infected, but she caught it just in time.' Buckley returned to the hub two or three more times after that to get her wound checked and ask more questions. 'I didn't have to sit at home and wonder like I did with my first baby,' she says. 'There were people I could talk to. That was missing the first time around, that extra layer of reassurance and support.' Yvonne Harris, 39, has a three-year-old child and lives in Firhouse, Dublin. Photograph Moya Nolan Problems in labour Yvonne Harris, 39, has a three-year-old child and lives in Firhouse, Dublin. Harris felt cared for throughout her pregnancy. 'I was given good information and was always listened to,' she says. 'It wasn't until I went in to labour that things started to go wrong.' She was 1.5cm dilated when she arrived at a busy labour ward. 'Because I was in the early stages of labour and the ward was full, I was placed in a room at the end of the hall with women whose pregnancies were being monitored, but who weren't in labour,' she says. Her husband had to leave when evening came. 'I'm quiet and don't like to make a fuss, and because everyone was so busy, I wasn't checked on much.' When she was examined the next morning, she was fully dilated and was rushed to the delivery suite. Her daughter was born by vacuum delivery, but Harris retained the placenta. Attempts to remove it manually resulted in haemorrhaging, and she had to be operated upon. She now wonders if her birth experience led to postnatal depression. 'It kicked in when my daughter was six months old and I treated it with medication and counselling,' she says. 'Talking helped release the trauma I'd held on to from the birth.' Looking back, she questions if her complications might have been avoided if her labour had been managed differently. 'If I'd asked for help more or if there had been more staff to check on me, things might have been different.' Click here to read our National Women's Health Survey. The Irish Examiner Women's Health Survey 2025 Ipsos B&A designed and implemented a research project for the Irish Examiner involving a nationally representative sample of n=1,078 women over the age of 16 years. The study was undertaken online with fieldwork conducted between April 30 and May 15, 2025. The sample was quota controlled by age, socio-economic class, region and area of residence to reflect the known profile of women in Ireland based on the census of population and industry agreed guidelines. Ipsos B&A has strict quality control measures in place to ensure robust and reliable findings; results based on the full sample carry a margin of error of +/-2.8%. In other words, if the research was repeated identically results would be expected to lie within this range on 19 occasions out of 20. A variety of aspects were assessed in relation to women's health including fertility, birth, menopause, mental health, health behaviour, and alcohol consumption.
Irish Times
4 days ago
- Irish Times
Trinity climbs to 75th in world university rankings
Trinity College Dublin , Ireland's highest-ranked third-level institution, has jumped 12 places to 75th in the latest set of world university rankings, while Ireland is the most improved higher education system in Europe. The QS World University Rankings 2026 show that seven of Ireland's eight universities have climbed up the global league table, boosted by factors such as employer reputation and the rising proportion of international staff and students. For the first time all Irish universities now feature among the world's top 800. While Trinity is the highest ranked, it is followed by UCD (118th, up eight places), UCC (246th, up 27 places), University of Galway (284th, down 11 places), University of Limerick (401st, up 20 places) and Dublin City University (410th, up 11 places). READ MORE In addition Maynooth University has climbed the rankings (771-780th, up from 801-850) along with Technological University Dublin (781-790, up from 851-900). The QS World University Rankings 2026 evaluate more than 1,500 universities across 100 countries and territories. Rank in Ireland 2026 rank 2025 rank Institution 1 75 87 Trinity College Dublin 2 118 =126 University College Dublin 3 246 =273 University College Cork 4 284 =273 University of Galway / Ollscoil na Gaillimhe 5 =401 =421 University of Limerick 6 =410 =421 Dublin City University 7 771-780 801-850 Maynooth University 8 781-790 851-900 Technological University of Dublin Overall, MIT in Cambridge, Massachusetts, retains its top position for the 14th year, followed by Imperial College London (second) – led by former UCD president Prof Hugh Brady – and Stanford University (third). While there are more than a dozen world university rankings, the QS version is considered by education observers as one of the 'big three', alongside Times Higher Education and Shanghai's Academic Ranking of World Universities. Critics say university rankings are not an accurate measure of performance and neglect key areas such as the quality of teaching and learning. They remain influential internationally, however, in areas such as reputation, research and student choice. The rankings show Trinity College Dublin improved across key indicators used such as academic reputation, international faculty and graduate outcomes. Trinity's provost Dr Linda Doyle said the rankings news 'encourages us to be even bolder in our ambition for Trinity and, indeed, for Ireland – an ambition that should be championed and defended regardless of the rankings'. She said a sustainable funding model for higher education in Ireland was key to helping it thrive. 'While increased core funding helps us to achieve our ambitions on the national and international stage, we need to see an absolute step-change in how universities and research are funded in Ireland.' Universities have welcomed additional core funding in the Budget 2025, but noted that a €307 million funding gap identified by Government in 2022 is still not fully closed. Ben Sowter, senior vice-president at QS, said Ireland's 'outstanding results' showed the country's campuses were increasingly 'open and diverse, which benefits both domestic and international students, as well as employers seeking globally minded talent'. He said Ireland outperformed many European counterparts and global English-speaking student destinations in key areas such as employer reputation, international faculty and sustainability. Every Irish university also improved its international students ratio, reflecting growing international appeal and diversity on Irish campuses. Mr Sowter said general improvements across the board in academic reputation also showed the increased regard in which institutions' research and educational innovativeness is held. 'Improving the ratio of faculty to students, heightening intensity of research undertaken at universities and ensuring graduates are supported to go on to make meaningful impacts on society will help Irish universities keep improving and making positive contributions to both Ireland and the globe,' he said. Globally, the US remains the most represented system, with 192 universities, and sees more institutions rise than fall in this edition. China has continued its ascent with Peking University holding on to its 14th place, while Tsinghua University rose to 17th, and Fudan University climbed nine spots to 30th, signalling a strong research-led push.
RTÉ News
12-06-2025
- RTÉ News
What's really in the air Dubliners breathe?
Analysis: You're certainly getting more than oxygen as DNA captured from the atmosphere shows exactly what's in the air in the capital city By Jenny Whilde, University of Florida It turns out that the air of the capital city also contains cats, dogs, rats, cannabis, poppy, and even magic mushrooms, or at least their DNA. This is the result of a new study that found DNA floating in the air in the city provides ample information to simultaneously identify not just larger plants and animals, but tiny insects, fungi, bacteria and even viruses. The research, led by Dr David Duffy, at the University of Florida's Whitney Laboratory for Marine Bioscience, involved taking air samples in Trinity College Dublin, in the heart of the city centre. There, two floors above the hustle and bustle of urban life, a small machine sucked city air through a tube like a vacuum cleaner. A week later, the machine is switched off and a small three-inch-long filter is detached from the end of the tube. The machine is then run again in rural locations in the Wicklow Mountains and at Wildlife Rehabilitation Ireland in the Boyne Valley Estuary. From RTÉ Radio 1's Today with Claire Byrne in 2023, new research reveals poor air quality in the capital The filters were brought back to the Trinity College Zoology Department and University College Dublin's Systems Biology Ireland. Originally pristine white, the filters now looked grey and dirty, but didn't appear to have caught anything that might be useful in identifying organisms. However, invisible to the naked eye, they hold the genetic code to thousands of species from each area. This code is environmental DNA (eDNA), DNA that has been shed naturally into the environment by the living things in the area. The scuff of a paw in the earth, a gust of wind blowing leaves from a tree or a cough or sneeze all release microscopic fragments that contain enough DNA to identify the source. Traditional approaches can only examine very short pieces of eDNA from a pre-selected subset of species. But a technique known as shotgun metagenomic sequencing allows scientists to rapidly sequence the genomes or partial genomes of a whole range of species in an area, rather than just one species of interest. The study, published in Nature Ecology and Evolution, was also able to determine the ancestry of bobcats (lynx) and venomous spiders whose DNA was hoovered up from air in a Florida forest. With little more than an air filter, and within a couple of days, scientists can identify endangered species and identify where they came from, without having to see, capture or stress the species being studied. Previously, eDNA was thought to consist of only low-quality degraded short fragments. The recovery of intact DNA from air enables much deeper, faster, and more affordable study of the animals, plants, fungi, bacteria and viruses, in all environments. Unsurprisingly, the research team found that the genetic ancestry of humans in the city centre was more diverse than in remote rural locations. A high amount of bumble bee DNA indicated the Trinity College Campus Pollinator Plan was working well. There was also plenty of cow and pig DNA in the city air – perhaps from burgers and ham sandwiches? What they hadn't expected to find was DNA from cannabis, poppy and even magic mushrooms. The animals, plants, fungi, biodiversity, pathogens (human, animal and crop), disease vectors, allergens, antimicrobial resistance genes and genetic diversity in an area can all be easily monitored and compared. The researchers identified different human pathogens from the air, including viruses and bacteria, with far more pathogens present in urban areas. Such surveillance could help scientists easily and rapidly track emerging diseases. From RTÉ Brainstorm, how a new app could show you green travel routes through Dublin The implications are huge for many different fields of research, including conservation, health and agriculture: surveying species that are difficult to observe; tracking changes in biological diversity over time; early identification of pest species and disease spread; screening for antimicrobial and pesticide resistance. Simultaneous and rapid surveillance of pathogens (such as Covid-19, potato blight, crayfish plague, wildlife viruses), invasive species (Japanese knotweed), endangered species, pest species, disease-vector species (such as mosquitoes), allergens and plant- and fungal-derived narcotics are all possible from air eDNA shotgun metagenomic sequencing. This technology does not come without concerns, especially when sampling in areas frequented by humans. We shed our DNA into the air just like other animal species. The study highlights ethical issues such as individual privacy, potential beneficial applications of eDNA technology for law enforcement purposes or worrying applications by surveillance states. These ethical issues need to be taken into serious consideration by the scientific and legislative communities, and guidelines around the safe and appropriate use of information gleaned from eDNA will need to be put in place. As technology that only existed in the sci-fi fantasies of our childhoods becomes a reality, it seems that we are closer than ever to developing a lifeform detection device as envisaged by Star Trek's tricorder.
